tag:theconversation.com,2011:/ca/topics/elements-23744/articlesElements – The Conversation2023-12-06T19:39:11Ztag:theconversation.com,2011:article/2191952023-12-06T19:39:11Z2023-12-06T19:39:11ZEarth may have had all the elements needed for life within it all along − contrary to theories that these elements came from meteorites<figure><img src="https://images.theconversation.com/files/563960/original/file-20231206-27-mh7rrg.jpg?ixlib=rb-1.1.0&rect=5%2C11%2C1994%2C1485&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Scientists still debate the origins of Earth's life-sustaining elements.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/hot-sunrise-in-space-royalty-free-image/160306742?phrase=Tobias+Roetsch+Future+Publishing+earth&adppopup=true">BlackJack3D/E+ via Getty Images</a></span></figcaption></figure><p>For many years, scientists have predicted that many of the <a href="https://www.khanacademy.org/science/ap-biology/chemistry-of-life/elements-of-life/a/matter-elements-atoms-article">elements that are crucial ingredients for life</a>, like sulfur and nitrogen, first came to Earth when asteroid-type objects carrying them crashed into our planet’s surface. </p>
<p>But new research <a href="https://doi.org/10.1126/sciadv.adh0670">published by our team</a> in Science Advances suggests that many of these elements, called volatiles, may have existed in the Earth from the beginning, while it formed into a planet.</p>
<p>Volatiles evaporate more readily than other elements. Common examples include carbon, hydrogen and nitrogen, though our research focused on a <a href="https://www.sciencedirect.com/topics/chemistry/chalcogen">group called chalcogens</a>. Sulfur, selenium and tellurium are all chalcogens.</p>
<p>Understanding how these volatile elements made it to Earth helps <a href="https://scholar.google.com/citations?user=DpHUpCwAAAAJ&hl=en">planetary scientists</a> <a href="https://scholar.google.com/citations?user=h0uFkzgAAAAJ&hl=zh-CN">like us</a> better understand Earth’s geologic history, and it could teach us more about the habitability of terrestrial planets beyond Earth. </p>
<h2>Why it matters</h2>
<p>The popular “late veneer” theory predicts that Earth first formed from <a href="https://www.ox.ac.uk/news/2017-09-27-volatile-processes-shaped-earth">materials that are low in volatiles</a>. After the formation of the Earth’s core, the theory says, the <a href="https://doi.org/10.1126/science.1186239">planet got volatiles</a> when volatile-rich bodies from the outer solar system hit the surface. </p>
<p>These objects brought <a href="https://doi.org/10.1007/978-3-642-11274-4_870">around a half a percent of Earth’s mass</a>. If the late veneer theory is right, then most elements that make up life arrived on Earth sometime <a href="https://physicsworld.com/a/how-the-earths-core-was-formed/">after the Earth’s core had formed</a>.</p>
<p>But our new research suggests that Earth had all its life-essential volatile elements from the very beginning, during the planet’s formation. These results challenge the late veneer theory and are consistent with another study <a href="https://newsroom.ucla.edu/releases/earth-like-planets-may-be-an-inevitability">tracing the origin of water on Earth</a>. </p>
<h2>How we did our work</h2>
<p>To study the origin of volatiles in the Earth, we used a computational technique called <a href="https://www.jeol.com/words/emterms/20121023.055758.php#gsc.tab=0">first-principles calculation</a>. This technique describes the <a href="https://www.ducksters.com/science/chemistry/radiation_and_radioactivity.php">behaviors of isotopes</a>, which are atoms of an element that have varying numbers of neutrons. You can think of an element as a family – every atom has the same number of protons, but <a href="https://theconversation.com/hunting-for-rare-isotopes-the-mysterious-radioactive-atomic-nuclei-that-will-be-in-tomorrows-technology-86177">different isotope cousins</a> have different numbers of neutrons.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/42gUZNYco0c?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Isotopes have a host of useful applications, from archaeology and medicine to planetary science.</span></figcaption>
</figure>
<p>Different isotopes behaved slightly differently during each stage of Earth’s formation. And the isotopes left behind a signature after each formation stage that scientists can use as a kind of fingerprint to track where they were throughout Earth’s formation. </p>
<p>First-principles calculation allowed us to calculate what isotope signatures we’d expect to see for different chalcogens, depending on how the Earth formed. We ran a few models and compared our isotope predictions for each model with the actual measurements of chalcogen isotopes on Earth.</p>
<p><a href="https://doi.org/10.1126/sciadv.adh0670">We found that</a> while many volatiles evaporated during Earth’s formation, when it was hot and glowing, many more are still left over today. Our findings suggest that most of the volatiles on Earth now are likely left over from the early stage of Earth’s formation.</p>
<h2>What’s next</h2>
<p>While chalcogens are interesting to study, future research should look at other critical-for-life volatiles, like nitrogen. And more research into how these volatiles behave <a href="https://education.nationalgeographic.org/resource/core/">under extreme conditions</a> could help us know more about how isotopes were behaving during each of the growth stages of Earth’s formation. </p>
<p>We also hope to use this approach to see <a href="https://theconversation.com/nasas-tess-spacecraft-is-finding-hundreds-of-exoplanets-and-is-poised-to-find-thousands-more-122104">whether some exoplanets</a> – planets beyond our solar system – could be <a href="https://theconversation.com/distant-star-toi-700-has-two-potentially-habitable-planets-orbiting-it-making-it-an-excellent-candidate-in-the-search-for-life-198274">habitable to life</a>.</p>
<p><em>The <a href="https://theconversation.com/us/topics/research-brief-83231">Research Brief</a> is a short take about interesting academic work.</em></p><img src="https://counter.theconversation.com/content/219195/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shichun Huang is funded by National Science Foundation, and UTK Gerald D. Sisk Endowed Professorship.</span></em></p><p class="fine-print"><em><span>Wenzhong Wang receives funding from the National Natural Science Foundation of China. </span></em></p>Scientists analyzing isotope ratios have found that many of the elements that make up life could be left over from Earth’s formation.Shichun Huang, Associate Professor of Earth and Planetary Sciences, University of TennesseeWenzhong Wang, Professor of Planetary Science, University of Science and Technology of ChinaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2146142023-10-24T12:22:02Z2023-10-24T12:22:02ZSpace rocks and asteroid dust are pricey, but these aren’t the most expensive materials used in science<figure><img src="https://images.theconversation.com/files/552576/original/file-20231006-23-aam2il.jpg?ixlib=rb-1.1.0&rect=0%2C34%2C5751%2C3794&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Meteorites can get pricey, but they're not the most expensive material. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/FranceMeteoriteAuction/e075e1b22656489db39610bafb0682af/photo?Query=meteorites&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=341&currentItemNo=5&vs=true">AP Photo/Thibault Camus</a></span></figcaption></figure><p>After a journey of seven years and nearly 4 billion miles, <a href="https://science.nasa.gov/mission/osiris-rex">NASA’s OSIRIS-REx</a> <a href="https://www.space.com/osiris-rex-asteroid-samples-land-houston">spacecraft landed</a> gently in the Utah desert on the morning of Sept. 24, 2023, with a precious payload. <a href="https://science.nasa.gov/mission/osiris-rex">The spacecraft</a> brought back a sample from the asteroid Bennu.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An artist's illustration of a gray metallic spacecraft hovering above the dark surface of an asteroid, with an arm that reaches down to the surface." src="https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/552573/original/file-20231006-27-cm9a07.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">OSIRIS-REx collected a sample from the asteroid Bennu.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/20c047ec48f74f6995ffad6b0f54422c?ext=true">NASA/Goddard Space Flight Center via AP</a></span>
</figcaption>
</figure>
<p>Roughly half a pound of material collected from the <a href="https://science.nasa.gov/solar-system/asteroids/101955-bennu/facts/">85 million-ton asteroid</a> (77.6 billion kg) will help scientists learn about the <a href="https://solarsystem.nasa.gov/missions/osiris-rex/in-depth/">formation of the solar system</a>, including whether <a href="https://solarsystem.nasa.gov/asteroids-comets-and-meteors/asteroids/101955-bennu/in-depth/">asteroids like Bennu</a> include the chemical ingredients for life.</p>
<p>NASA’s mission was budgeted at <a href="https://www.asteroidmission.org/qa/">US$800 million</a> and will end up costing around <a href="https://www.planetary.org/space-policy/cost-of-osiris-rex">$1.16 billion</a> for <a href="https://www.nasa.gov/news-release/nasas-first-asteroid-sample-has-landed-now-secure-in-clean-room/">just under 9 ounces of sample</a> (255 g). But is this the most expensive material known? Not even close.</p>
<p>I’m a <a href="https://scholar.google.com/citations?user=OrRLRQ4AAAAJ&hl=en">professor of astronomy</a>. I use Moon and Mars rocks in my teaching and have a modest collection of meteorites. I marvel at the fact that I can hold in my hand something that is billions of years old from billions of miles away.</p>
<h2>The cost of sample return</h2>
<p>A handful of asteroid works out to $132 million <a href="https://www.hoodmwr.com/things-that-weigh-around-1-ounce/">per ounce</a>, or $4.7 million per gram. That’s about 70,000 times the <a href="https://goldprice.org/">price of gold</a>, which has been in the range of $1,800 to $2,000 per ounce ($60 to $70 per gram) for the past few years.</p>
<p>The first extraterrestrial material returned to Earth came from the Apollo program. Between 1969 and 1972, six Apollo missions brought back 842 pounds (382 kg) of <a href="https://curator.jsc.nasa.gov/lunar/">lunar samples</a>.</p>
<p>The <a href="https://www.planetary.org/space-policy/cost-of-apollo">total price tag</a> for the Apollo program, adjusted for inflation, was $257 billion. These Moon rocks were a relative bargain at $19 million per ounce ($674 thousand per gram), and of course Apollo had additional value in demonstrating technologies for human spaceflight. </p>
<p>NASA is planning to bring samples back from Mars in the early 2030s to see if any contain traces of ancient life. The <a href="https://mars.nasa.gov/msr/">Mars Sample Return</a> mission aims to return <a href="https://www.universetoday.com/161264/we-can-only-bring-30-samples-of-mars-back-to-earth-how-do-we-decide/">30 sample tubes</a> with a <a href="https://downloads.regulations.gov/NASA-2022-0002-0002/attachment_5.pdf">total weight of a pound</a> (450 g). The <a href="https://science.nasa.gov/mission/mars-2020-perseverance">Perseverance rover</a> has already <a href="https://www.universetoday.com/160109/perseverance-is-building-up-a-big-collection-of-mars-samples/">cached 10 of these samples</a>. </p>
<p>However, <a href="https://www.science.org/content/article/mars-sample-return-got-new-price-tag-it-s-big">costs have grown</a> because the mission is complex, involving multiple robots and spacecraft. Bringing back the samples could run $11 billion, putting their cost at $690 million per ounce ($24 million per gram), five times the unit cost of the Bennu samples.</p>
<h2>Some space rocks are free</h2>
<p>Some space rocks cost nothing. Almost 50 tons of free samples from the solar system <a href="https://science.nasa.gov/solar-system/meteors-meteorites/">rain down on the Earth</a> every day. Most burn up in the atmosphere, but if they reach the ground <a href="https://www.amnh.org/explore/news-blogs/on-exhibit-posts/meteor-meteorite-asteroid">they’re called meteorites</a>, and most of those come from asteroids. </p>
<p><a href="https://www.nhm.ac.uk/discover/types-of-meteorites.html">Meteorites can get costly</a> because it can be difficult to recognize and retrieve them. Rocks all look similar unless you’re a geology expert. </p>
<p>Most meteorites are stony, <a href="https://www.britannica.com/science/chondrite">called chondrites</a>, and they can be bought online for as little as $15 per ounce (50 cents per gram). Chondrites differ from normal rocks in containing <a href="https://www.amnh.org/exhibitions/permanent/meteorites/origins-of-the-solar-system/chondrules">round grains called chondrules</a> that formed as molten droplets in space at the birth of the solar system 4.5 billion years ago.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A meteorite that looks like a long gray rock with dark gray veins running across it." src="https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=305&fit=crop&dpr=1 600w, https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=305&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=305&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=384&fit=crop&dpr=1 754w, https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=384&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/552568/original/file-20231006-19-kgbnz8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=384&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A chondrite from the Viñales meteorite, which originated from the asteroid belt between Mars and Jupiter.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Ordinary_chondrite_%28Vi%C3%B1ales_Meteorite%29_15.jpg">Ser Amantio di Nicolao/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p><a href="https://aerolite.org/shop/iron-meteorites/">Iron meteorites</a> are distinguished by a dark crust, caused by melting of the surface as they come through the atmosphere, and an internal pattern of long metallic crystals. They cost $50 per ounce ($1.77 per gram) or even higher. <a href="https://geology.com/meteorites/value-of-meteorites.shtml">Pallasites</a> are stony-iron meteorites laced with the mineral olivine. When cut and polished, they have a translucent yellow-green color and can cost over $1,000 per ounce ($35 per gram).</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A brown-gray meteorite that's roughly circular with textured ridges" src="https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/552571/original/file-20231006-21-vjnv0r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An iron meteorite.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Odessa_%28iron%29_meteorite.jpg">Llez/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>More than a few meteorites have reached us from the Moon and Mars. Close to 600 have been recognized as <a href="https://sites.wustl.edu/meteoritesite/items/lunar-meteorites/">coming from the Moon</a>, and <a href="https://www.catawiki.com/en/stories/4683-10-most-expensive-meteorites-ever-offered-up-on-earth">the largest</a>, weighing 4 pounds (1.8 kg), sold for a price that works out to be about $4,700 per ounce ($166 per gram). </p>
<p>About 175 meteorites are identified as <a href="https://www2.jpl.nasa.gov/snc/">having come from Mars</a>. <a href="https://aerolite.org/shop/mars-meteorites/">Buying one</a> would cost about $11,000 per ounce ($388 per gram). </p>
<p>Researchers can figure out <a href="https://science.nasa.gov/solar-system/meteors-meteorites/facts/">where meteorites come from</a> by using their landing trajectories to project their paths back to the asteroid belt or comparing their composition with different classes of asteroids. Experts can tell where Moon and Mars rocks come from by their geology and mineralogy.</p>
<p>The limitation of these “free” samples is that there is no way to know where on the Moon or Mars they came from, which limits their scientific usefulness. Also, they start to get contaminated as soon as they land on Earth, so it’s hard to tell if any microbes within them are extraterrestrial.</p>
<h2>Expensive elements and minerals</h2>
<p>Some elements and minerals are expensive because they’re scarce. Simple <a href="http://www.leonland.de/elements_by_price/en/list">elements in the periodic table</a> have low prices. Per ounce, carbon costs one-third of a cent, iron costs 1 cent, aluminum costs 56 cents, and even mercury is less than a dollar (per 100 grams, carbon costs $2.40, iron costs less than a cent and alumnium costs 19 cents). Silver is $14 per ounce (50 cents per gram), and gold, $1,900 per ounce ($67 per gram). </p>
<p><a href="https://alansfactoryoutlet.com/how-much-do-elements-cost-the-price-of-75-elements-per-kilogram/">Seven radioactive elements</a> are extremely rare in nature and so difficult to create in the lab that they eclipse the price of NASA’s Mars Sample Return. Polonium-209, the most expensive of these, costs $1.4 trillion per ounce ($49 billion per gram).</p>
<p>Gemstones can be expensive, too. <a href="https://www.gemsociety.org/article/emerald-jewelry-and-gemstone-information/">High-quality emeralds</a> are 10 times the <a href="https://goldprice.org/">price of gold</a>, and <a href="https://ajediam.com/diamond-prices/white-natural-diamond/">white diamonds</a> are 100 times the price of gold. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A circular white diamond sitting on a white surface." src="https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=727&fit=crop&dpr=1 600w, https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=727&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=727&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=914&fit=crop&dpr=1 754w, https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=914&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/554101/original/file-20231016-15-63z3ek.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=914&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">High-quality white diamonds can cost millions of dollars.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/eeaab33d812a487ebfd2e5a76a25eb03?ext=true">AP Photo/Mary Altaffer</a></span>
</figcaption>
</figure>
<p>Some diamonds have a boron impurity that gives them a <a href="https://www.diamonds.pro/education/blue/">vivid blue hue</a>. They’re found in only a handful of mines worldwide, and at <a href="https://www.usatoday.com/story/money/2022/04/28/worlds-largest-blue-diamond-sells/9567999002/">$550 million per ounce</a> ($19 million per gram) they rival the cost of the upcoming Mars samples – an ounce is 142 carats, but very few gems are that large. </p>
<p>The <a href="https://www.sciencealert.com/scientists-create-world-s-most-expensive-material-valued-at-145-million-per-gram">most expensive synthetic material</a> is a tiny spherical “cage” of carbon with a nitrogen atom trapped inside. The atom inside the cage is extremely stable, so can be used for timekeeping. <a href="https://arstechnica.com/science/2015/12/oxford-company-now-selling-endohedral-fullerenes-priced-at-110-million-per-gram/">Endohedral fullerenes</a> are made of carbon material that may be used to create extremely accurate atomic clocks. They can cost $4 billion per ounce ($141 million per gram).</p>
<h2>Most expensive of all</h2>
<p><a href="https://www.livescience.com/32387-what-is-antimatter.html">Antimatter</a> occurs in nature, but it’s exceptionally rare because any time an antiparticle is created it quickly annihilates with a particle and produces radiation. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/7MkfMGzMcf8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">At CERN’s ‘antimatter factory,’ scientists create antimatter in very small quantities.</span></figcaption>
</figure>
<p>The <a href="https://royalsocietypublishing.org/doi/10.1098/rsta.2010.0026">particle accelerator at CERN</a> can produces 10 million antiprotons per minute. That sounds like a lot, but <a href="https://archive.ph/6RUrA">at that rate</a> it would take billions of years and cost a billion billion (10<sup>18</sup>) dollars to generate an ounce (3.5 x 10<sup>16</sup> dollars per gram). </p>
<p><a href="https://www.newscientist.com/article/mg24232342-600-how-star-treks-warp-drives-touch-on-one-of-physics-biggest-mysteries/">Warp drives</a> as envisaged by “Star Trek,” which are powered by matter-antimatter annihilation, will have to wait.</p><img src="https://counter.theconversation.com/content/214614/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Impey receives funding from the National Science Foundation. </span></em></p>Some space rocks you can get for free – if you know how to identify them. Rarer materials cost more, and the asteroid sample NASA just brought back has a high price tag.Chris Impey, University Distinguished Professor of Astronomy, University of ArizonaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1679822021-10-07T12:22:51Z2021-10-07T12:22:51ZAncient groundwater: Why the water you’re drinking may be thousands of years old<figure><img src="https://images.theconversation.com/files/425134/original/file-20211006-19-hm7er4.jpg?ixlib=rb-1.1.0&rect=871%2C578%2C3009%2C2087&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Some of North America’s groundwater is so old, it fell as rain before humans arrived here thousands of years ago.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/senior-woman-holding-glass-of-water-close-up-royalty-free-image/961181838">Maria Fuchs via Getty Images</a></span></figcaption></figure><p>Communities that rely on the Colorado River are facing a water crisis. Lake Mead, the river’s largest reservoir, has fallen to levels not seen since it was created by the construction of the Hoover Dam roughly a century ago. Arizona and Nevada are <a href="https://theconversation.com/as-colorado-river-basin-states-confront-water-shortages-its-time-to-focus-on-reducing-demand-165646">facing their first-ever mandated water cuts</a>, while water is being <a href="https://coloradosun.com/2021/07/19/lake-powell-drought-blue-mesa-reservoir-drained/">released from other reservoirs</a> to keep the Colorado River’s hydropower plants running.</p>
<p>If even the mighty Colorado and its reservoirs are not immune to the heat and drought worsened by climate change, where will the West get its water?</p>
<p>There’s one hidden answer: underground.</p>
<p>As rising temperatures and drought dry up rivers and melt mountain glaciers, people are increasingly dependent on the water under their feet. Groundwater resources currently supply <a href="http://nora.nerc.ac.uk/id/eprint/19395/">drinking water to nearly half the world’s population</a> and <a href="https://doi.org/10.1016/j.jog.2011.05.001">roughly 40% of water used for irrigation globally</a>.</p>
<p>What many people don’t realize is how old – and how vulnerable – much of that water is.</p>
<p>Most water stored underground has been there for decades, and much of it has sat for hundreds, thousands or even millions of years. Older groundwater tends to reside deep underground, where it is <a href="https://theconversation.com/water-underground-source-for-billions-could-take-more-than-a-century-to-respond-fully-to-climate-change-110551">less easily affected by surface conditions</a> such as drought and pollution.</p>
<p>As shallower wells dry out under the pressure of urban development, population growth and climate change, old groundwater is becoming increasingly important.</p>
<h2>Drinking ancient groundwater</h2>
<p>If you bit into a piece of bread that was 1,000 years old, you’d probably notice.</p>
<p>Water that has been underground for a thousand years can taste different, too. It leaches natural chemicals from the surrounding rock, changing its mineral content. Some natural contaminants <a href="https://www.usgs.gov/center-news/lithium-us-groundwater">linked to groundwater age</a> – <a href="https://doi.org/10.1192/bjp.2020.128">like mood-boosting lithium</a> – can have positive effects. Other contaminants, like iron and manganese, can be troublesome. </p>
<p>Older groundwater is also sometimes <a href="https://doi.org/10.1029/2021GL093549">too salty to drink</a> without expensive treatment. This problem can be worse near the coasts: Overpumping creates space that can draw seawater into aquifers and contaminate drinking supplies.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Illustration of layers of groundwater below the surface" src="https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=386&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=386&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=386&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=485&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=485&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423398/original/file-20210927-25-wpt4qy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=485&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Flow timescales of groundwater through different layers.</span>
<span class="attribution"><a class="source" href="https://www.wtamu.edu/~cbaird/sq/2013/07/16/how-do-wells-get-their-water-from-underground-rivers">USGS</a></span>
</figcaption>
</figure>
<p>Ancient groundwater can take thousands of years to replenish naturally. And, as California saw during its 2011-2017 drought, natural underground storage spaces compress as they empty, so they <a href="https://doi.org/10.1002/2016WR019861">can’t refill to their previous capacity</a>. This compaction in turn causes the land above to crack, buckle and sink.</p>
<p>Yet people today are <a href="https://www.wpr.org/without-enough-water-go-around-farmers-california-are-exhausting-aquifers">drilling deeper wells in the West</a> as droughts deplete surface water and farms rely more heavily on groundwater.</p>
<h2>What does it mean for water to be ‘old’?</h2>
<p>Let’s imagine a rainstorm over central California 15,000 years ago. As the storm rolls over what’s now San Francisco, most of the rain falls into the Pacific Ocean, where it will eventually evaporate back into the atmosphere. However, some rain also falls into rivers and lakes and over dry land. As that rain seeps through layers of soil, it enters slowly trickling “flowpaths” of underground water.</p>
<p>Some of these paths lead deeper and deeper, where water collects in crevices within the bedrock hundreds of meters underground. The water gathered in these underground reserves is in a sense cut off from the active water cycle – at least on timescales relevant to human life.</p>
<p>In California’s arid Central Valley, <a href="https://linkinghub.elsevier.com/retrieve/pii/S0022169416302773">much of the accessible ancient water</a> has been <a href="https://www.science.org/doi/10.1126/sciadv.abf3503">pumped out</a> of the earth, mostly for agriculture. Where the natural replenishment timescale would be on the order of millennia, agricultural seepage <a href="https://www.science.org/doi/10.1126/sciadv.abf3503">has partially refilled some aquifers with newer</a> – too often polluted – water. In fact, places like Fresno now actively refill aquifers with clean water (such as treated wastewater or stormwater) in a process known as “<a href="https://www.americangeosciences.org/geoscience-currents/managed-aquifer-recharge">managed aquifer recharge</a>.”</p>
<figure class="align-center ">
<img alt="Map showing longest turnover times are in the West and Great Plains" src="https://images.theconversation.com/files/424251/original/file-20211001-23-taw2of.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424251/original/file-20211001-23-taw2of.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=534&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424251/original/file-20211001-23-taw2of.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=534&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424251/original/file-20211001-23-taw2of.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=534&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424251/original/file-20211001-23-taw2of.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=671&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424251/original/file-20211001-23-taw2of.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=671&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424251/original/file-20211001-23-taw2of.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=671&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Average turnover times for groundwater in the U.S.</span>
<span class="attribution"><span class="source">Alan Seltzer, based on data from Befus et al 2017</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>In 2014, midway through their worst drought in modern memory, California became the last western state <a href="https://water.ca.gov/programs/groundwater-management/sgma-groundwater-management">to pass a law</a> requiring local groundwater sustainability plans. Groundwater may be resilient to heat waves and climate change, but if you use it all, you’re in trouble.</p>
<p>One response to water demand? Drill deeper. Yet that answer <a href="https://theconversation.com/drilling-deeper-wells-is-a-band-aid-solution-to-us-groundwater-woes-121219">isn’t sustainable</a>.</p>
<p>First, it’s expensive: Large agricultural companies and lithium mining firms tend to be the sort of investors who can afford to drill deep enough, while <a href="https://www.nytimes.com/2021/08/14/us/drought-california-water-shortage.html">small rural communities can’t</a>. </p>
<p>Second, once you pump ancient groundwater, aquifers need time to refill. Flowpaths may be disrupted, choking off a natural water supply to springs, wetlands and rivers. Meanwhile, the change in pressure underground can destabilize the earth, <a href="https://ca.water.usgs.gov/land_subsidence/california-subsidence-areas.html">causing land to sink</a> and even <a href="https://doi.org/10.1029/2019GL083491">leading to earthquakes</a>.</p>
<figure class="align-right ">
<img alt="Chart showing how nitrates enter water as more groundwater is pumped out" src="https://images.theconversation.com/files/422559/original/file-20210922-21-blruso.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/422559/original/file-20210922-21-blruso.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=684&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422559/original/file-20210922-21-blruso.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=684&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422559/original/file-20210922-21-blruso.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=684&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422559/original/file-20210922-21-blruso.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=860&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422559/original/file-20210922-21-blruso.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=860&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422559/original/file-20210922-21-blruso.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=860&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Pumping accelerates groundwater flow to a well, delivering dissolved chemicals.</span>
<span class="attribution"><a class="source" href="https://www.usgs.gov/media/images/nitrate-groundwater-pumping">USGS</a></span>
</figcaption>
</figure>
<p>Third is contamination: While deep, mineral-rich ancient groundwater is often cleaner and safer to drink than younger, shallower groundwater, overpumping can change that. As water-strapped regions rely more heavily on deep groundwater, overpumping lowers the water table and draws down polluted modern water that can mix with the older water. This mixing <a href="https://www.usgs.gov/news/increased-pumping-california-s-central-valley-during-drought-worsens-groundwater-quality">causes the water quality to deteriorate</a>, leading to demand for ever-deeper wells.</p>
<h2>Reading climate history in ancient groundwater</h2>
<p>There are other reasons to care about ancient groundwater. Like actual fossils, extremely old “fossil groundwater” can teach us about the past. </p>
<p>Envision our prehistoric rainstorm again: 15,000 years ago, the climate was quite different from today. Chemicals that dissolved in ancient groundwater are detectable today, opening windows into a past world. Certain dissolved chemicals act as clocks, telling scientists the groundwater’s age. For example, we know how fast dissolved carbon-14 and krypton-18 decay, so we can measure them to calculate when the water last interacted with air. </p>
<p>Younger groundwater that disappeared underground after the 1950s has a unique, man-made chemical signature: high levels of tritium from atomic bomb testing.</p>
<figure class="align-center ">
<img alt="Illustration of water flowing among rocks, close up and at a distance." src="https://images.theconversation.com/files/422556/original/file-20210922-26-tcnb2j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422556/original/file-20210922-26-tcnb2j.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=369&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422556/original/file-20210922-26-tcnb2j.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=369&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422556/original/file-20210922-26-tcnb2j.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=369&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422556/original/file-20210922-26-tcnb2j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=464&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422556/original/file-20210922-26-tcnb2j.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=464&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422556/original/file-20210922-26-tcnb2j.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=464&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The various components and properties of an unconfined aquifer.</span>
<span class="attribution"><a class="source" href="https://pubs.usgs.gov/gip/gw/how_a.html">USGS</a></span>
</figcaption>
</figure>
<p>Other dissolved chemicals behave like tiny thermometers. Noble gases like argon and xenon, for instance, dissolve more in cold water than in warm water, along a precisely known temperature curve. Once groundwater is isolated from air, dissolved noble gases don’t do much. As a result, they preserve information about environmental conditions at the time the water first seeped into the subsurface.</p>
<p>The concentrations of noble gases in fossil groundwater have provided some of our most reliable estimates of <a href="https://doi.org/10.1038/s41586-021-03467-6">temperature on land during the last ice age</a>. Such findings provide insight into modern climates, including how sensitive Earth’s average temperature is to carbon dioxide in the atmosphere. These methods support a <a href="https://doi.org/10.1038/s41586-020-2617-x">recent study</a> that found 3.4 degrees Celsius of warming with each doubling of carbon dioxide.</p>
<h2>Groundwater’s past and future</h2>
<p>People in some regions, like New England, have been drinking ancient groundwater for years with little danger of exhausting usable supplies. Regular rainfall and varied water sources – including surface water in lakes, rivers and snowpack – provide alternatives to groundwater and also refill aquifers with new water. If aquifers can keep up with the demand, the water <a href="https://doi.org/10.1038/s41561-020-0629-7">can be used sustainably</a>. </p>
<p>Out West, though, over a century of unmanaged and exorbitant water use means that some of the places most dependent on groundwater – arid regions vulnerable to drought – have squandered the ancient water resources that once existed underground.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cross section of California showing rivers, groundwater and wells, including recharge wells" src="https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=355&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=355&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=355&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=446&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=446&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424254/original/file-20211001-27-1f9d7aq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=446&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">How water use and recharge fit into the hydrological cycle.</span>
<span class="attribution"><a class="source" href="https://www.waterboards.ca.gov/rwqcb2/water_issues/programs/groundwater_protection.html">State of California</a></span>
</figcaption>
</figure>
<p>A famous precedent for this problem is in the Great Plains. There, the ancient water of the Ogallala Aquifer supplies drinking water and irrigation for millions of people and farms from South Dakota to Texas. If people were to pump this aquifer dry, <a href="https://blogs.scientificamerican.com/observations/farmers-deplete-fossil-water-in-worlds-breadbaskets/">it would take thousands of years to refill naturally</a>. It is a vital buffer against drought, yet irrigation and water-intensive farming <a href="https://theconversation.com/farmers-are-depleting-the-ogallala-aquifer-because-the-government-pays-them-to-do-it-145501">are lowering its water levels at unsustainable rates</a>. </p>
<p>As the planet warms, ancient groundwater is becoming increasingly important – whether flowing from your kitchen tap, irrigating food crops, or offering warnings about Earth’s past that can help us prepare for an uncertain future.</p>
<p>[<em>Understand new developments in science, health and technology, each week.</em> <a href="https://theconversation.com/us/newsletters/science-editors-picks-71/?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=science-understand">Subscribe to The Conversation’s science newsletter</a>.]</p><img src="https://counter.theconversation.com/content/167982/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>As surface water diminishes in the Western US, people are drilling deeper wells – and tapping into older groundwater that can take thousands of years to replenish naturally.Marissa Grunes, Environmental Fellow, Harvard UniversityAlan Seltzer, Assistant Scientist in Marine Chemistry and Geochemistry, Woods Hole Oceanographic InstitutionKevin M. Befus, Assistant Professor of Hydrogeology, University of ArkansasLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1639862021-07-07T20:07:49Z2021-07-07T20:07:49ZWe found a new type of stellar explosion that could explain a 13-billion-year-old mystery of the Milky Way’s elements<figure><img src="https://images.theconversation.com/files/410093/original/file-20210707-21-qxb5cu.jpeg?ixlib=rb-1.1.0&rect=50%2C13%2C2196%2C1404&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">NASA/WikiCommons</span></span></figcaption></figure><p>Until recently it was thought neutron star mergers were the only way <a href="https://pls.llnl.gov/research-and-development/nuclear-science/project-highlights/livermorium/elements-113-and-115">heavy elements</a> (heavier than Zinc) could be produced. These mergers involve the mashup of the remnants of two massive stars in a binary system. </p>
<p>But we know heavy elements were first produced not long after the Big Bang, when the universe was really young. Back then, not enough time had passed for neutron star mergers to have even occurred. Thus, another source was needed to explain the presence of early heavy elements in the Milky Way.</p>
<p>The discovery of an ancient star SMSS J2003-1142 in the Milky Way’s halo — which is the roughly spherical region that surrounds the galaxy — is providing the first evidence for another source for heavy elements, including uranium and possibly gold. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=647&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=647&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=647&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=813&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=813&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410107/original/file-20210707-13-vbdmhd.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=813&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Around our galaxy, the Milky Way, there is a ‘halo’ made up of hot gases which is continually being supplied with material ejected by birthing or dying stars. Only 1% of stars in the galaxy are found in the halo.</span>
<span class="attribution"><span class="source">NASA</span></span>
</figcaption>
</figure>
<p>In our research <a href="https://dx.doi.org/10.1038/s41586-021-03611-2">published today</a> in Nature, we show the heavy elements detected in SMSS J2003-1142 were likely produced, not by a neutron star merger, but through the collapse and explosion of a rapidly spinning star with a strong magnetic field and a mass about 25 times that of the Sun.</p>
<p>We call this explosion event a “magnetorotational hypernova”. </p>
<h2>Stellar alchemy</h2>
<p>It was recently <a href="https://www.space.com/strontium-heavy-element-formed-neutron-star-merger.html">confirmed</a> that neutron star mergers are indeed one source of the heavy elements in our galaxy. As the name suggests, this is when two neutron stars in a binary system merge together in an energetic event called a “kilonova”. This process produces heavy elements.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410108/original/file-20210707-25-uv3eud.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Binary star systems have two stars orbiting around a common centre of mass. A neutron star merger is a type of stellar collision that happens between two neutron stars in a binary system. This process can produce heavy elements.</span>
<span class="attribution"><span class="source">NASA</span></span>
</figcaption>
</figure>
<p>However, existing models of the chemical evolution of our galaxy indicate that neutron star mergers <em>alone</em> could not have produced the specific patterns of elements we see in multiple ancient stars, including SMSS J2003-1142.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/signals-from-a-spectacular-neutron-star-merger-that-made-gravitational-waves-are-slowly-fading-away-94294">Signals from a spectacular neutron star merger that made gravitational waves are slowly fading away</a>
</strong>
</em>
</p>
<hr>
<h2>A relic from the early universe</h2>
<p>SMSS J2003-1142 was first observed in 2016 from Australia, and then again in September 2019 using a telescope at the European Southern Observatory in Chile.</p>
<p>From these observations, we studied the star’s chemical composition. Our analysis revealed an iron content roughly 3,000 times lower than the Sun’s. In other words, SMSS J2003-1142 is chemically primitive. </p>
<p>The elements we observed in it were likely produced by a single parent star, just after the Big Bang. </p>
<h2>Signatures of a collapsed rapidly spinning star</h2>
<p>The chemical composition of SMSS J2003-1142 can reveal the nature and properties of its parent star. Particularly important are its unusually high amounts of nitrogen, zinc and heavy elements including europium and uranium. </p>
<p>The high nitrogen levels in SMSS J2003-1142 indicate the parent star had rapid rotation, while high zinc levels indicate the energy of the explosion was about ten times that of a “normal” supernova — which means it would have been a hypernova. Also, large amounts of uranium would have required the presence of lots of neutrons. </p>
<p>The heavy elements we can observe in SMSS J2003-1142 today are all evidence that this star was produced as a result of an early magnetorotational hypernova explosion.</p>
<p>And our work has therefore provided the first evidence that magnetorotational hypernova events are a source of heavy elements in our galaxy (alongside neutron star mergers).</p>
<h2>What about neutron star mergers?</h2>
<p>But how do we know it wasn’t just neutron star mergers that led to the particular elements we find in SMSS J2003-1142? There’s a few reasons for this.</p>
<p>In our hypothesis, a single parent star would have made all the elements observed in SMSS J2003-1142. On the other hand, it would have taken much, much longer for the same elements to have been made only through neutron star mergers. But this time wouldn’t have even existed this early in the galaxy’s formation when these elements were made.</p>
<p>Also, neutron star mergers make <em>only</em> heavy elements, so additional sources such as regular supernova would had to have occurred to explain other heavy elements, such as calcium, observed in SMSS J2003-1142. This scenario, while possible, is more complicated and therefore less likely.</p>
<p>The magnetorotational hypernovae model not only provides a better fit to the data, it can also explain the composition of SMSS J2003-1142 through a single event. It could be neutron star mergers, together with magnetorotational supernovae, could in unison explain how all the heavy elements in the Milky Way were created. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-race-to-find-even-more-new-elements-to-add-to-the-periodic-table-52747">The race to find even more new elements to add to the periodic table</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/163986/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Yong receives funding from the Australian Research Council. He is affiliated with the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D). </span></em></p><p class="fine-print"><em><span>Gary Da Costa has received funding from the Australian Research Council. He is affiliated with the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D).</span></em></p>The discovery of an ancient star in the Milky Way’s halo is providing evidence for another source that would have produced the galaxy’s heavy elements.David Yong, Academic, Research School of Astronomy and Astrophysics, Australian National UniversityGary Da Costa, Emeritus Professor of Astronomy, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1238532019-10-18T05:52:59Z2019-10-18T05:52:59ZOur ability to manufacture minerals could transform the gem market, medical industries and even help suck carbon from the air<figure><img src="https://images.theconversation.com/files/297110/original/file-20191015-98636-u508ph.JPG?ixlib=rb-1.1.0&rect=0%2C5%2C3964%2C2988&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Pictured is a slag pile at Broken Hill in New South Wales. Slag is a man-made waste product created during smelting. </span> <span class="attribution"><span class="source">Anita Parbhakar-Fox</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Last month, scientists <a href="https://www.theage.com.au/national/victoria/this-meteorite-came-from-the-core-of-another-planet-inside-it-a-new-mineral-20190830-p52mhg.html">uncovered</a> a mineral called Edscottite. Minerals are solid, naturally occurring substances that are not living, such as quartz or haematite. This new mineral was discovered after an examination of the <a href="https://collections.museumvictoria.com.au/specimens/328">Wedderburn Meteorite</a>, a metallic-looking rock found in Central Victoria back in 1951. </p>
<p>Edscottite is made of iron and carbon, and was likely formed within the core of another planet. It’s a “true” mineral, meaning one which is naturally occurring and formed by geological processes either on Earth or in outer-space.</p>
<p>But while the Wedderburn Meteorite held the first-known discovery of Edscottite, other new mineral discoveries have been made on Earth, of substances formed as a result of human activities such as mining and mineral processing. These are called anthropogenic minerals.</p>
<p>While true minerals comprise the majority of the approximately 5,200 known minerals, there are about <a href="https://deepcarbon.net/feature/humanitys-minerals">208</a> human-made minerals which have been approved as minerals by the International Mineralogical Association. </p>
<p>Some are made on purpose and others are by-products. Either way, the ability to manufacture minerals has vast implications for the future of our rapidly growing population.</p>
<h2>Modern-day alchemy</h2>
<p>Climate change is one of the biggest challenges we face. While governments debate the future of coal-burning power stations, carbon dioxide continues to be released into the atmosphere. We need innovative strategies to capture it. </p>
<p>Actively manufacturing minerals such as <a href="http://www.webmineral.com/data/Nesquehonite.shtml#.XYL-sGkzaCg">nesquehonite</a> is one possible approach. It has applications in building and construction, and making it requires removing carbon dioxide from the atmosphere.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-explained-why-carbon-dioxide-has-such-outsized-influence-on-earths-climate-123064">Climate explained: why carbon dioxide has such outsized influence on Earth's climate</a>
</strong>
</em>
</p>
<hr>
<p>Nesquehonite occurs naturally when magnesian rocks slowly break down. It has been identified at the <a href="https://www.mindat.org/loc-266123.html">Paddy’s River mine</a> in the Australian Capital Territory and locations <a href="https://rruff.info/doclib/MinMag/Volume_34/34-268-370.pdf">in New South Wales</a>.</p>
<p>But scientists discovered it can also be <a href="https://www.frontiersin.org/articles/10.3389/fenrg.2016.00003/full">made</a> by passing carbon dioxide into an alkaline solution and having it react with magnesium chloride or sodium carbonate/bicarbonate. </p>
<p>This is a growing area of <a href="https://www.mdpi.com/2075-163X/7/9/172/htm">research</a>. </p>
<p>Other synthetic minerals such as hydrotalcite are produced when asbestos tailings passively absorb atmospheric carbon dioxide, as discovered by scientists at the <a href="https://www.sciencedaily.com/releases/2018/12/181212134430.htm">Woodsreef asbestos mine in New South Wales</a>. </p>
<p>You could say this is a kind of “modern-day alchemy” which, if taken advantage of, could be an effective way to suck carbon dioxide from the air at a large scale.</p>
<h2>Meeting society’s metal demands</h2>
<p>Mining and mineral processing is designed to recover metals from ore, which is a natural occurrence of rock or sediment containing sufficient minerals with economically important elements. But through mining and mineral processing, new minerals can also be created. </p>
<p>Smelting is used to produce a range of commodities such as lead, zinc and copper, by heating ore to high temperatures to produce pure metals. </p>
<p>The process also produces a glass-like waste product called slag, which is deposited as molten liquid, <a href="https://www.youtube.com/watch?v=T7kDNo3rIM4">resembling lava</a>.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/297051/original/file-20191015-98640-hlhncu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">This is a backscattered electron microscope image of historical slag collected from a Rio Tinto mine in Spain.</span>
<span class="attribution"><span class="source">Image collected by Anita Parbhakar-Fox at the University of Tasmania (UTAS)</span></span>
</figcaption>
</figure>
<p>Once cooled, the textural and mineralogical similarities between lava and slag are crystal-clear. </p>
<p>Micro-scale inspection shows human-made minerals in slag have a unique ability to accommodate metals into their crystal lattice that would not be possible in nature.</p>
<p>This means metal recovery from mine waste (a potential secondary resource) could be an effective way to supplement society’s growing metal demands. The challenge lies in developing processes which are cost effective.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/wealth-in-waste-using-industrial-leftovers-to-offset-climate-emissions-49249">Wealth in waste? Using industrial leftovers to offset climate emissions</a>
</strong>
</em>
</p>
<hr>
<h2>Ethically-sourced jewellery</h2>
<p>Our increasing knowledge on how to manufacture minerals may also have a major impact on the growing synthetic <a href="https://lightboxjewelry.com/">gem manufacturing industry</a>.</p>
<p>In 2010, the world was awestruck by the engagement ring given to Duchess of Cambridge Kate Middleton, valued at about <a href="https://news.thediamondstore.co.uk/facts-kate-middletons-engagement-ring/">£300,000</a> (AUD$558,429).</p>
<p>The ring has a 12-carat blue sapphire, surrounded by 14 solitaire diamonds, with a setting made from 18-carat white gold.</p>
<p>Replicas of it have been acquired by people across the globe, but for only a fraction of the price. How?</p>
<p>In 1837, Marc Antoine Gardin demonstrated that sapphires (mineralogically known as corundum or aluminium oxide) can be replicated by reacting metals with other substances such as chromium or boric acid. This produces a range of seemingly identical coloured stones. </p>
<p>On close examination, some properties may vary such as the presence of flaws and air bubbles and the stone’s hardness. But only a gemologist or gem enthusiast would likely notice this.</p>
<p>Diamonds can also be <a href="https://www.nytimes.com/2018/05/29/business/synthetic-diamond-production.html">synthetically made</a>, through either a high pressure, high temperature, or chemical vapour deposition process.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=466&fit=crop&dpr=1 600w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=466&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=466&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=586&fit=crop&dpr=1 754w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=586&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/297118/original/file-20191015-98648-x3d02t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=586&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Synthetic diamonds have essentially the same chemical composition, crystal structure and physical properties as natural diamonds.</span>
<span class="attribution"><span class="source">Instytut Fizyki Uniwersytet Kazimierza Wielkiego</span></span>
</figcaption>
</figure>
<p>Creating synthetic gems is increasingly important as natural stones are becoming more difficult and expensive to source. In some countries, the rights of miners are also violated and this poses <a href="https://www.hrw.org/report/2018/02/08/hidden-cost-jewelry/human-rights-supply-chains-and-responsibility-jewelry">ethical concerns</a>. </p>
<h2>Medical and industrial applications</h2>
<p>Synthetic gems have industrial applications too. They can be used in window manufacturing, semi-conducting circuits and cutting tools. </p>
<p>One example of an entirely manufactured mineral is something called yttrium aluminum garnet (or YAG) which can be used as a <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/ndyag-laser">laser</a>.</p>
<p>In medicine, these lasers are used to correct glaucoma. In dental surgery, they allow soft gum and tissues to be cut away. </p>
<p>The move to develop new minerals will also support technologies enabling deep space exploration through the creation of <a href="https://narang.seas.harvard.edu/quantum-materials">‘quantum materials’</a>. </p>
<p>Quantum materials have unique properties and will help us create a new generation of electronic products, which could have a significant impact on space travel technologies. Maybe this will allow us to one day visit the birthplace of Edscottite?</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-quantum-materials-may-soon-make-star-trek-technology-reality-86378">How quantum materials may soon make Star Trek technology reality</a>
</strong>
</em>
</p>
<hr>
<p>In decades to come, the number of human-made minerals is <a href="http://blogs.discovermagazine.com/d-brief/2017/03/03/man-made-minerals-human-epoch/#.XaU045Mzai4">set to increase</a>. And as it does, so too does the opportunity to find new uses for them.</p>
<p>By expanding our ability to manufacture minerals, we could reduce pressure on existing resources and find new ways to tackle global challenges.</p><img src="https://counter.theconversation.com/content/123853/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Manufacturing minerals is an expanding field of study. Making more of them could help alleviate various pressures faced by our growing population. But how are they made, and where can they be used?Anita Parbhakar-Fox, Senior Research Fellow in Geometallurgy/Applied Geochemistry, The University of QueenslandPaul Gow, Principal Research Fellow, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1179062019-07-17T19:49:37Z2019-07-17T19:49:37ZWhen an artist looks at a chemical element, what do they see?<figure><img src="https://images.theconversation.com/files/283811/original/file-20190712-173342-ypail1.jpg?ixlib=rb-1.1.0&rect=231%2C28%2C2728%2C1498&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artists Damon Kowarsky and Hyunju Kim produced a series of 51 artistic interpretations of elements from the Periodic Table.
</span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p>Artistic depictions of several chemical elements feature in a new exhibition from today as part of Australia’s celebrations for the <a href="https://www.iypt2019.org/">International Year of the Periodic Table</a>.</p>
<p>They are the work of artists <a href="http://damon.tk/">Damon Kowarsky</a> and Hyunju Kim, who worked together since December 2018 on the renditions that will be on display at <a href="https://www.quantumvictoria.vic.edu.au/">Quantum Victoria</a>, a specialist science and mathematics centre in the northern suburbs of Melbourne.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=418&fit=crop&dpr=1 600w, https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=418&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=418&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=525&fit=crop&dpr=1 754w, https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=525&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/282978/original/file-20190708-51262-gc4990.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=525&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Damon Kowarsky and Hyunju Kim.</span>
<span class="attribution"><span class="source">Photo credit Delilah Yu</span></span>
</figcaption>
</figure>
<p>The project followed a chance meeting between Damon and Soula Bennett, the director of Quantum Victoria. Soula believes Science, Technology, Engineering and Mathematics (STEM) naturally extend to incorporate art.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-periodic-table-from-its-classic-design-to-use-in-popular-culture-52822">The periodic table: from its classic design to use in popular culture</a>
</strong>
</em>
</p>
<hr>
<p>So Damon and Kim were commissioned to produce a series of 51 artistic interpretations illustrating elements of significance in the story of the birth of the universe from the Periodic Table.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/283665/original/file-20190711-173329-ibd8mi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mat Greentree and Damon Kowarsky installing some of the works at Quantum.</span>
<span class="attribution"><span class="source">Photo credit Hyunju Kim</span></span>
</figcaption>
</figure>
<p>While Kowarsky was responsible for creating the drawings of the panels, the colours are by Kim.</p>
<p>As scientists who work with many elements from a scientific point of view, we were curious as to how Kowarsky chose some of the representations he did, so we asked him to describe the artistic process for some of his favourite elements. </p>
<h2>Helium (<a href="http://www.rsc.org/periodic-table/element/2/helium">He</a>)</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The helium (He) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> Used for balloons and to make your voice sound funny as it’s lighter and less dense than air.</p>
<p><strong>Chemist’s view:</strong> An unreactive (noble) gas that is particularly useful in cooling applications – liquid helium at -269°C is used to keep magnets at a superconducting temperature. Element with the lowest boiling point.</p>
<p><strong>Artist’s view (Damon):</strong> Helium is colourless, odourless, tasteless, almost completely inert, not commonly found on Earth, and named after the Sun, whose image dominated the design I completed for hydrogen.</p>
<p>Not a promising start in terms of visualisation! </p>
<p>In many ways it’s the most abstract of elements, and this ultimately was the clue that unlocked the design. The background composition is structured around a chart showing the passage of the Sun through the sky at the latitude and longitude of <a href="https://www.charleslatrobecollege.vic.edu.au/">Charles La Trobe College</a> (in Melbourne, the site of the installation) on January 1.</p>
<p>Overlaid onto this is the sequence of helium formation in stellar nucleosynthesis, a graph showing the rates of production and consumption of helium (despite its prevalence in the universe it’s a finite resource on Earth) and the bars of the absorption spectrum that allowed this, the first ever extraterrestrial element, to be discovered.</p>
<h2>Iron (<a href="http://www.rsc.org/periodic-table/element/26/iron">Fe</a>)</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279645/original/file-20190616-158925-1n32ffh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The iron (Fe) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> Used to make steel. Iron ore is the source of much of Australia’s wealth. Found in blood.</p>
<p><strong>Chemist’s view:</strong> The most common element on Earth, making up around 35% of the its mass. Iron is used to catalyse a very important chemical reaction, the combination of nitrogen and hydrogen into ammonia, an essential component of fertiliser. </p>
<p><strong>Artist’s view:</strong> Iron is a pivotal element in the Periodic Table in terms of how the elements are created.</p>
<p>Showing a cross section of Earth allowed me to talk about its prevalence, maintain design coherence through the repetition of circles, and introduce bold and saturated colours. The smaller circle represents a red blood cell (iron is found in haemoglobin) and the pie charts show the relative distribution of iron isotopes.</p>
<p>In the bottom left corner the alchemical symbol for iron (Mars, the masculine attribute) breaks into the form of Earth. Alchemy is important as one of the foundations of modern chemistry and its symbols are historically and visually interesting. I didn’t want it to dominate though, so using a negative shape seemed a good way to balance all these concerns.</p>
<h2>Copper (<a href="http://www.rsc.org/periodic-table/element/29/copper">Cu</a>)</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The copper (Cu) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> For the older generation, copper pipes and <a href="https://www.ramint.gov.au/one-cent">1</a> and <a href="https://www.ramint.gov.au/two-cents">2</a> cent coins.</p>
<p><strong>Chemist’s view:</strong> Metal with very high thermal and electrical conductivity. Very useful for catalysing some chemical reactions, especially a so-called click reaction where two molecules can be quickly linked together under mild conditions.</p>
<p><strong>Artist’s view:</strong> With copper there’s the amazing colour and its history as one of the oldest metals known to humans.</p>
<p>I relied on the element’s utility and familiarity, and wanted to step away from symmetry and the geometric prevalence of circles. Even though copper is inorganic, its malleability and ductility lends an almost lifelike quality to its forms.</p>
<p>A map of Cyprus (copper is named for the place it was first discovered and mined) contributes to the overall balanced asymmetry of the design.</p>
<h2>Calcium (<a href="http://www.rsc.org/periodic-table/element/20/calcium">Ca</a>)</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The calcium (Ca) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> Found in limestone, chalk and coral, and bones and teeth. </p>
<p><strong>Chemist’s view:</strong> Highly reactive and the most abundant metal in the human body. As calcium chloride, used as a desiccant to remove water from air and solvents so reactions can be done anhydrously (without the presence of water, which can interfere with some reactions).</p>
<p><strong>Artist’s view:</strong> Calcium is common in bones, shells and teeth. The challenge was finding images that were visually interesting and fitted the hexagonal shape.</p>
<p>Happily, this collection of human bones found on the web was neither articulated nor hopelessly jumbled. I was pleased how the curved bones (rib and collar) echo other design elements.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The energy artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p>Shells of course follow the Fibonacci Curve, whose elegant spiral can be seen in the another panel of the exhibit (“Energy”), where it represents a timeline of the universe.</p>
<h2>Nitrogen (<a href="http://www.rsc.org/periodic-table/element/7/nitrogen">N</a>)</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The nitrogen (N) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> Forms about 78% of Earth’s atmosphere, found in proteins and nucleic acids (DNA, RNA), and a key component of fertilisers.</p>
<p><strong>Chemist’s view:</strong> The triple bond (N≡N) form of nitrogen found in the atmosphere, is the second strongest bond in any diatomic molecule (composed of two elements). Although problematic for chemistry, it is useful as it releases large amounts of energy when broken. This is used both for fertilisers and explosives, and remains an essential process in the chemical industry.</p>
<p><strong>Artist’s view:</strong> Nitrogen compounds are essential for life. There are two main ways atmospheric nitrogen is converted to forms that are usable by plants and animals.</p>
<p>The first is lightning.</p>
<p>The second, and much less dramatic, is the symbiotic relationship between bacteria and the roots of certain plants. Typically these are beans and legumes but Australian wattles and acacias also contain nitrogen-fixing nodules. </p>
<h2>Other artistic elements</h2>
<p>Of course, Damon Kowarsky and Hyunju Kim are not the first to take an artistic look at the elements.</p>
<p>Other examples include a <a href="https://www.bowdoin.edu/news/2019/02/a-first-years-extraordinary-periodic-table.html">graphic artist’s version by Julie Hu</a> to convey to non-scientists the richness of what these substances bring to our world.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/silver-makes-beautiful-bling-but-its-also-good-for-keeping-the-bacterial-bugs-away-115367">Silver makes beautiful bling but it's also good for keeping the bacterial bugs away</a>
</strong>
</em>
</p>
<hr>
<p>Another is a <a href="https://www.sciencehistory.org/distillations/magazine/the-periodic-table-printmaking-project">periodic table printmaking project by Jennifer Schmitt</a>, the daughter of a chemistry teacher mother and an artistic father, she grew up seeing beauty in science.</p>
<p>There is also a <a href="http://www.instantshift.com/2015/09/02/periodic-table-elements-character-design/">depiction of the elements as characters by Kaycie Dunlap</a>, who was inspired by a desire make science more interesting by imagining what the elements would look like in our regular life.</p>
<p>Multiple quilting projects have drawn inspiration from sources such as the elements’ names, unique characteristics, and purposes (<a href="https://hyperallergic.com/236928/quirky-quilts-inspired-by-the-periodic-table/">curated by artist Jill Rumoshosky Werner in 2015</a>) or the wonderful stories about people, cultures, history, art, politics and science associated with them (<a href="https://periodictableinfabric.com/about-the-project/">curated by Kim Baird</a>).</p>
<hr>
<p><em>The artworks are on display from July 18, 2019, at Quantum Victoria, 235 Kingsbury Drive, Macleod, Victoria (they’re also <a href="http://art.damon.fastmail.net/project/science/periodictable/perindex.htm">available online</a>).</em></p>
<p><em>If you’d like to see them please call (03) 9223 1460 or email at <a href="mailto:admin@quantumvictoria.vic.edu.au">admin@quantumvictoria.vic.edu.au</a> to arrange a visit, as this is a school site (co-located with Charles La Trobe P-12 College).</em></p><img src="https://counter.theconversation.com/content/117906/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Blaskovich is a member of the Royal Australian Chemical Institute (RACI) and the American Chemical Society.</span></em></p><p class="fine-print"><em><span>Frances Separovic receives funding from Australian Research Council (ARC) and National Health & Medical Research Council (NHMRC). She is a member of the American Chemical Society, ANZMAG, Biophysical Society, ISMAR and RACI.</span></em></p>From heavy metal to lighter than air gas, these elements and others from the Periodic Table are transformed into artworks that go on display from today.Mark Blaskovich, Senior Research Officer, The University of QueenslandFrances Separovic AO FAA, Professor of Chemistry, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1153612019-05-26T19:31:16Z2019-05-26T19:31:16ZTitanium is the perfect metal to make replacement human body parts<figure><img src="https://images.theconversation.com/files/275791/original/file-20190521-23835-38tcg8.jpg?ixlib=rb-1.1.0&rect=0%2C409%2C3149%2C1765&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Titanium is used in knee and hip replacements.</span> <span class="attribution"><span class="source">Monstar Studio/Shutterstock</span></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at how researchers study some of the elements in their work.</em></p>
<p><em>Today’s it’s titanium, a metal known for its strength and lightness so it’s ideal for making replacement hips, knees and other parts of our bodies, but it’s also used in other industries.</em></p>
<hr>
<p><a href="http://www.rsc.org/periodic-table/element/22/titanium">Titanium</a> gets its name from the <a href="https://www.britannica.com/topic/Titan-Greek-mythology">Titans of ancient Greek mythology</a> but this thoroughly modern material is well suited to a huge range of high-tech applications.</p>
<p>With the chemical symbol Ti and an atomic number of 22, titanium is a silver-coloured metal valued for its low density, high strength, and resistance to corrosion.</p>
<p>I first studied titanium via a Master’s degree at the Institute of Metal Research in the Chinese Academy of Sciences in 1999. One of my projects was to investigate the formation of titanium alloys for their high-strength characteristics.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/from-the-bronze-age-to-food-cans-heres-how-tin-changed-humanity-114195">From the bronze age to food cans, here's how tin changed humanity</a>
</strong>
</em>
</p>
<hr>
<p>Since then, the applications for this metal have grown exponentially, from its use (as <a href="https://www.britannica.com/science/titanium-dioxide">titanium dioxide</a>) in paints, paper, toothpaste, sunscreen and cosmetics, through to its <a href="https://www.britannica.com/science/titanium">use as an alloy</a> in biomedical implants and aerospace innovations.</p>
<p>Particularly exciting is the perfect marriage between titanium and 3D printing.</p>
<h2>Custom design from 3D printing</h2>
<p>Titanium materials are expensive and can be problematic when it comes to traditional processing technologies. For example, its high melting point (1,670°C, much higher than <a href="https://www.bssa.org.uk/topics.php?article=103">steel alloys</a>) is a challenge.</p>
<p>The relatively low-cost precision of 3D printing is therefore a game-changer for titanium. 3D printing is where an object is built layer by layer and designers can create amazing shapes.</p>
<p>This allows the production of complex shapes such as replacement parts of a <a href="https://www.abc.net.au/news/2017-03-30/victorian-woman-gets-3d-printed-jawbone-implant/8400410">jaw bone</a>, <a href="https://www.abc.net.au/news/2014-10-21/rare-cancer-sufferer-receives-3d-printed-heel/5830432">heel</a>, <a href="https://www.southampton.ac.uk/news/2014/05/16-ground-breaking-hip-and-stem-cell-surgery.page">hip</a>, <a href="https://www.ncbi.nlm.nih.gov/pubmed/27313616">dental implants</a>, or <a href="http://www.media-studio.co.uk/news/media-studios-first-3d-printed-titanium-cranioplasty-plate-delivered">cranioplasty plates</a> in surgery. It can also be used to make <a href="https://3dprint.com/219546/3d-print-golf-clubs-and-equipment/">golf clubs</a> and <a href="https://www.reuters.com/article/us-norsk-boeing-idUSKBN17C264">aircraft components</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/8Np_NVNx2UI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Even beer containers benefit from 3D printing with titanium.</span></figcaption>
</figure>
<p>The <a href="https://www.csiro.au/en/Research/MF/Areas/Metals/Lab22">CSIRO is working with industry</a> to develop new technologies in 3D printing using titanium. (It even <a href="https://www.youtube.com/watch?v=8oc8GoOOUo4">made a dragon</a> out of titanium.) </p>
<p>Advances in 3D printing are opening up new avenues to further improve the function of <a href="https://www.materialise.com/pl/node/3197">customised bodypart implants</a> <a href="https://www.renishaw.com/en/metal-3d-printing-for-healthcare--24226">made of titanium</a>.</p>
<p>Such implants can be designed to be porous, making them lighter but allowing blood, nutrients and nerves to pass through and can even <a href="https://3dprint.com/219795/3d-printed-lattice-structures/">promote bone in-growth</a>.</p>
<h2>Safe in the body</h2>
<p>Titanium is considered the most biocompatible metal – not harmful or toxic to living tissue – due to its resistance to corrosion from bodily fluids. This ability to withstand the harsh bodily environment is a result of the protective oxide film that forms naturally in the presence of oxygen.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hydrogen-fuels-rockets-but-what-about-power-for-daily-life-were-getting-closer-112958">Hydrogen fuels rockets, but what about power for daily life? We're getting closer</a>
</strong>
</em>
</p>
<hr>
<p>Its ability to physically bond with bone also gives titanium an advantage over other materials that require the use of an adhesive to remain attached. Titanium implants last longer, and much larger forces are required to break the bonds that join them to the body compared with their alternatives.</p>
<p>Titanium alloys commonly used in load-bearing implants are significantly less stiff – and closer in performance to human bone – than stainless steel or cobalt-based alloys.</p>
<h2>Aerospace applications</h2>
<p>Titanium weighs about half as much as steel but is 30% stronger, which makes it ideally suited to the aerospace industry where every gram matters.</p>
<p>In the late 1940s the US government helped to get production of titanium going as it could see its potential for “<a href="https://titaniumprocessingcenter.com/titanium-technical-data/titanium-history-developments-and-applications/">aircraft, missiles, spacecraft, and other military purposes</a>”.</p>
<p>Titanium has increasingly become the buy-to-fly material for aircraft designers striving to develop faster, lighter and more efficient aircraft.</p>
<p>About 39% of the US Air Force’s <a href="https://www.airforce-technology.com/projects/f22/">F22 Raptor</a>, one of the most advanced fighter aircraft in the world, is made of titanium.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A titanium 3D printed part (bottom) alongside the aluminum part (top) it will replace on an F-22 Raptor: the titanium part will not corrode, can be procured faster, and costs less.</span>
<span class="attribution"><a class="source" href="https://www.afrc.af.mil/News/Article/1734558/first-metallic-3d-printed-part-installed-on-f-22/">US Air Force photo by R. Nial Bradshaw</a></span>
</figcaption>
</figure>
<p>Civil aviation moved in the same direction with Boeing’s new <a href="https://www.sciencedirect.com/topics/engineering/boeing-787-dreamliner">787 Dreamliner made of 15% titanium</a>, significantly more than previous models.</p>
<p>Two key areas where titanium is used in airliners is in their landing gear and jet engines. Landing gear needs to withstand the massive amounts of force exerted on it every time a plane hits a runway.</p>
<p>Titanium’s toughness means it can absorb the huge amounts of energy expelled when a plane lands without ever weakening.</p>
<p>Titanium’s heat resistance means it can be used inside modern jet engines, where temperatures can reach 800°C. Steel begins to soften at around 400°C but titanium can withstand the intense heat of a jet engine without losing its strength.</p>
<h2>Where to find titanium</h2>
<p>In its natural state, titanium is always found bonded with other elements, usually within igneous rocks and sediments derived from them.</p>
<p>The most commonly mined materials containing titanium are <a href="https://geology.com/minerals/ilmenite.shtml">ilmenite</a> (an iron-titanium oxide, FeTiO<sub>3</sub>) and <a href="https://geology.com/minerals/rutile.shtml">rutile</a> (a titanium oxide, TiO<sub>2</sub>).</p>
<p>Ilmenite is most abundant in China, whereas Australia has the highest global proportion of rutile, <a href="http://www.ga.gov.au/education/classroom-resources/minerals-energy/australian-mineral-facts/titanium#heading-6">about 40% according to Geoscience Australia</a>. It’s found mostly on the east, west and southern coastlines of Australia.</p>
<p>Both materials are generally extracted from sands, after which the titanium is separated from the other minerals.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/where-did-you-grow-up-how-strontium-in-your-teeth-can-help-answer-that-question-112705">Where did you grow up? How strontium in your teeth can help answer that question</a>
</strong>
</em>
</p>
<hr>
<p>Australia is one of the world’s <a href="https://minerals.usgs.gov/minerals/pubs/commodity/titanium/mcs-2015-timin.pdf">leading producers of titanium</a>, producing more than 1.5 million tonnes in 2014. South Africa and China are the two next leading producers of titanium, producing 1.16 and 1 million tonnes, respectively.</p>
<p>Being among the top ten most abundant elements in Earth’s crust, titanium resources aren’t currently under threat – good news for the many scientists and innovators constantly looking for new ways to improve life with titanium.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/8oc8GoOOUo4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How to make a dragon using titanium!</span></figcaption>
</figure>
<hr>
<p><em>If you’re an academic researcher working with a particular element from the periodic table and have an interesting story to tell then why not <a href="https://theconversation.com/au/pitches">get in touch</a>.</em></p><img src="https://counter.theconversation.com/content/115361/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laichang Zhang receives funding from Australian Research Council through Discovery Projects. </span></em></p>Titanium is a tough but light metal that makes great replacements for bone in our body. But it has plenty of other uses in industry as well.Laichang Zhang, Professor Mechanical Engineering, Edith Cowan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1105152019-04-02T13:21:14Z2019-04-02T13:21:14ZFrom medicine to nanotechnology: how gold quietly shapes our world<figure><img src="https://images.theconversation.com/files/266772/original/file-20190401-177163-1hbwmu2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">itti ratanakiranaworn/Shutterstock</span></span></figcaption></figure><p>The periodic table of chemical elements <a href="https://www.iypt2019.org/">turns 150</a> this year. The anniversary is a chance to shine a light on particular elements – some of which seem ubiquitous but which ordinary people beyond the world of chemistry probably don’t know much about.</p>
<p>One of these is gold, which was the subject of my postgraduate degrees in chemistry, and which I have <a href="https://www.researchgate.net/profile/Werner_Van_Zyl">been studying</a> for almost 30 years. In chemistry, gold can be considered a late starter when compared to most other metals. It was always considered to be chemically “inert” – but in recent decades it has flourished and a variety of interesting applications have emerged. </p>
<h2>A long, curious history</h2>
<p>Gold takes its name from the Latin word aurum (“yellow”). It’s an element with a long but rather mysterious history. For instance, it’s one of 12 confirmed elements on the periodic table whose discoverer <a href="http://www.rsc.org/periodic-table/element/79/gold">is unknown</a>. The others are carbon, sulfur, copper, silver, iron, tin, antimony, mercury, lead, zinc and bismuth.</p>
<p>Though we’re not sure who discovered it, there’s evidence to suggest it was known to the ancient Egyptians as far back as <a href="http://raregoldnuggets.com/?p=6724">3000 BC</a>. Historically, its primary use was for jewellery; this is still the case <a href="https://www.sbcgold.com/blog/top-6-common-uses-for-gold/">today</a>, it’s also used in mint coins. Gold is also found in ancient and modern art: it’s used to prepare ruby or purple pigment, or as gold leaf.</p>
<p>South Africa was once the top <a href="https://www.forbes.com/sites/greatspeculations/2018/06/13/top-10-gold-producing-countries/#7580dae84a87">gold-producing country</a> by far: it mined over 1,000 tonnes in 1970 alone. Its annual output has steadily fallen since then – the top three gold producing countries <a href="https://www.forbes.com/sites/greatspeculations/2018/06/13/top-10-gold-producing-countries/#7580dae84a87">in 2017</a> were China, Australia and Russia, with a <em>combined</em> output of almost 1000 tonnes. South Africa has dropped to 8th position, even surpassed by Peru and Indonesia. </p>
<p>But gold’s uses and its chemical properties extend into many other areas beyond jewels and minted coins. From pharmaceutical research to nanotechnology, this ancient element is being used to drive new technologies that are pushing the world into the future.</p>
<h2>Why and how it’s useful</h2>
<p>Of the 118 confirmed elements in the periodic table, nine are naturally occurring elements with radioactive <a href="http://www.world-nuclear.org/information-library/non-power-nuclear-applications/radioisotopes-research/radioisotopes-in-medicine.aspx">isotopes</a> that are used in so-called nuclear medicine. Gold is not radioactive, but is nevertheless very useful in medicine in the form of gold-containing drugs. </p>
<p>There are <a href="https://link.springer.com/article/10.1007/BF03214741">two classes</a> of gold drugs used to treat rheumatoid arthritis. One is injectable gold thiolates – molecules with a sulfur atom at one end, and a chemical chain of virtually any description attached to them – found in drugs such as Myocrisin, Solganol and Allocrysin. The other is an oral complex called <a href="https://www.drugbank.ca/drugs/DB00995">Auranofin</a>. </p>
<p>Gold is also increasingly being used in <a href="https://www.nature.com/collections/btvngkffdj">nanotechnology</a>. A nanomaterial is generally considered a material where any of its three dimensions is 100 nanometres (nm) or less. Nanotechnology is useful because it is not restricted to a particular material – any material could in principle be made into a nanomaterial – but rather a particular property: the property of size. </p>
<p>For example, gold in its bulk form has a distinct yellow colour. But as it is broken up into very small pieces it starts to change colour, through a range of red and purple, depending on the relative size of the gold nanoparticles. Such nanoparticles could be used in a variety of applications, for example in the <a href="https://www.sciencedirect.com/science/article/pii/S0039914018302054">biomedical</a> or <a href="https://www.azonano.com/article.aspx?ArticleID=3284">optical-electronic</a> fields. </p>
<p>Another exciting advancement for gold in nanotechnology was the discovery in 1983 that a clean gold surface dipped into a solution containing a thiolate could form <a href="https://pubs.rsc.org/en/content/articlepdf/2010/cs/b907301a">self-assembled monolayers</a>. These monolayers modify the surface of gold in very innovative ways. Research into surface modification is important because the surface of anything can show very different properties than the bulk (that is, the inside) of the same material. </p>
<h2>More to come</h2>
<p>Gold nanoparticles have also proven to be an effective catalyst. A catalyst is a material that increases the rate of a chemical reaction and so reduces the amount of energy required without itself undergoing any permanent chemical change. This is important because catalysis lies at the heart of many <a href="https://www.anl.gov/article/7-things-you-may-not-know-about-catalysis">manufactured goods</a> we use today. For example, a catalyst turns propylene into propylene oxide, which is the first step in making antifreeze. </p>
<p>Two discoveries in the 1980s made scientists look at gold catalysis differently. Masatake Haruta, in Osaka, Japan, made mixed oxides containing gold – and <a href="https://pubs.acs.org/doi/abs/10.1021/acscatal.5b01122">discovered</a> the material was remarkably active to catalyse the oxidation of toxic carbon monoxide into carbon dioxide. Today, this catalyst is found in vehicle exhausts.</p>
<p>At the same time <a href="https://www.cardiff.ac.uk/people/view/38519-hutchings-graham">Graham Hutchings</a>, who was working in industry in Johannesburg, South Africa, <a href="https://www.nature.com/articles/nchem.388">discovered a gold catalyst</a> that would work best for acetylene hydrochlorination. This process is central to PVC plastic, which is used in virtually all plumbing production. Until then, the industrial catalyst for this process was using environmentally unfriendly mercuric chloride material. </p>
<h2>Many applications</h2>
<p>In my opinion, gold has many more uses that haven’t yet been discovered. There is much more to come in the world of <a href="https://pubs.acs.org/doi/10.1021/ed400782p">gold research</a>. </p>
<p>There will, in the next few years, be new developments in how the element is used in, amongst others, medicine, nanotechnology and catalysis. It will also find new applications in relativistic quantum chemistry (combining relativistic mechanics with quantum chemistry), surface science (the physics and chemistry of surfaces and how they interact), luminescence and <a href="https://onlinelibrary.wiley.com/doi/10.1002/9783527626724.ch5">photophysics</a> – and more.</p><img src="https://counter.theconversation.com/content/110515/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Werner van Zyl does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Gold is one of 12 confirmed elements on the periodic table whose discoverer is unknown.Werner van Zyl, Associate Professor of Chemistry, Lecturer in sustainable biomass, energy and water systems, University of KwaZulu-NatalLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1141952019-03-28T18:09:26Z2019-03-28T18:09:26ZFrom the bronze age to food cans, here’s how tin changed humanity<figure><img src="https://images.theconversation.com/files/266240/original/file-20190328-139341-e5mo6b.jpg?ixlib=rb-1.1.0&rect=0%2C475%2C4288%2C2355&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tin comes from the ore cassiterite.</span> <span class="attribution"><span class="source">Shutterstock/PYP </span></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at how researchers study some of the elements in their work.</em></p>
<p><em>Today’s it’s tin, a chemical that has little use by itself, but mix it with other elements and it takes on a whole new life.</em></p>
<hr>
<p>Mention tin and most people would think of the typical tin can, used to preserve foods you store in your cupboards. Tin is used here to help protect the can against corrosion (although <a href="https://www.ucan-packaging.com/blog/what-are-tin-cans-made-of/">not all cans</a> today contain tin).</p>
<p>But while the use of tin in canning only <a href="http://www.cancentral.com/content/nicolas-appert-father-canning">dates back to the early 1800s</a>, the mixing of tin with other elements dates back many centuries.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=393&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=393&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=393&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=493&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=493&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=493&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The tin in cans helps to protect them from corrosion.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/tsausawest/8508069576/">Flickr/Salvation Army USA West</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Tin – <a href="http://www.rsc.org/periodic-table/element/50/tin">chemical symbol Sn</a> with an atomic number 50 on the periodic table – is soft and silvery in colour, with a melting point of only 232°C. At first sight it doesn’t seem to be a promising prospect for making anything. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/where-did-you-grow-up-how-strontium-in-your-teeth-can-help-answer-that-question-112705">Where did you grow up? How strontium in your teeth can help answer that question</a>
</strong>
</em>
</p>
<hr>
<p>Somehow, humans discovered that adding controlled amounts of tin to copper produced a splendid, golden-yellow alloy we call bronze.</p>
<p>I first became interested in bronze during my final year undergraduate research project in 1978. That interest continues today – I’m working with colleagues in Thailand to reverse-engineer the technologies used to make ancient Thai bronze bangles. </p>
<h2>Early bronze</h2>
<p>The first known tin bronzes seem to have appeared in the Caucasus region of Eurasia in about 5800 to 4600 BCE. That these very scarce early examples of tin bronze may have been accidentally made from rather rare ores that naturally contained both copper and tin simultaneously.</p>
<p>There is abundant evidence that by about 3000 BCE, tin bronzes were being made in the Aegean and Middle East (Turkey, Syria, Iraq, Iran) by deliberately alloying tin and copper, with the ores being obtained from separate sources.</p>
<p>Clearly, a series of somewhat unlikely events had to occur before this could be the norm.</p>
<p>An accidental melt would have to have been made from suitable minerals containing oxides of tin and copper. The resulting metal would have to be recognised to have desirable properties, such as hardness, colour and toughness, such that superior weapons or ornaments could be produced.</p>
<p>Craftspeople would then have had to be organised enough to be able to work out how to repeat this smelting process to create artefacts such as swords, axe heads, bowls and bangles.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=392&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=392&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=392&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=492&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=492&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=492&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This 4000-year-old bronze axe with a low tin content was found in Sweden.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/historiska/4655950292/">Flickr/The Swedish History Museum</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Trading networks then had to be established to bring the comparatively rare tin from faraway places, such as Afghanistan or Cornwall in Britain’s southwest, to any foundry. The metallurgical craft would have to be passed on to other practitioners, probably by oral means.</p>
<h2>The spread of bronze</h2>
<p>The trick of deliberately adding tin to copper then spread throughout the Old World, reaching Western Europe by about 2800 BCE, Egypt by 2200 BCE, the populous North China Plain by 2200 BCE, China’s Yunnan province by about 1400 BCE, Thailand by about 1100 BCE, and southern India by 1000 BC (if not a century or two earlier).</p>
<p>This has led to some robust discussion among archaeometallurgists on whether the special knowledge of tin’s useful attributes spread from a single founding location in the Middle East, or whether it had been repeatedly independently developed by indigenous craftspeople.</p>
<p>In the case of Thailand and Cambodia, arguments have been raised for several scenarios: that the technology was independently developed, that it was brought south from China (or maybe the reverse, exported from northeast Thailand to China), or that it was imported from Bengal.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=369&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=369&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=369&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=464&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=464&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=464&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An ancient Thai bronze bangle from a site at Sa Kweo in east Thailand.</span>
<span class="attribution"><span class="source">Courtesy of Dr Supitcha Supansomboon and Assoc Prof Seriwat Saminpanya</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>With China, some local scholars have favoured the view for independent local discovery of tin bronze, although it the balance of evidence suggests that the knowledge was transmitted by horseriding visitors from West Asia.</p>
<h2>African bronze</h2>
<p>Tin was also mined in precolonial times in Southern Africa, and some bronze artefacts – such as pieces of metal sheet or ingots – have been recovered at old metalworking sites there.</p>
<p>The available evidence for this region suggests the technology for producing and working iron, copper and bronze appeared contemporaneously at locations in sub-Saharan Africa, beginning about 500 BCE in the north and reaching South Africa in about 300 CE.</p>
<p>How did the metallurgical knowledge get to Southern Africa? Was it an indigenous discovery of the Bantu of East Africa that was then carried with them on their migrations, or was the skill transmitted southwards from the Middle East, and if so by who and how? </p>
<p>As in the case of Asia, interpretation of these issues can be coloured by modern political sensibilities. The question of the source of the metalworking skills that produced the beautiful copper and gold ornaments of the ancient city of Mapungubwe in South Africa, for example, has still not been settled. </p>
<h2>Bronze in the Americas</h2>
<p>The ancient cultures of the Americas also developed sophisticated skills for processing precious metals, copper and tin.</p>
<p>They were able to manufacture bronze artefacts such as rings, pendants, body ornaments, ornamental tweezers, sheet metal breastplates, large discs, ornamental shields and especially bells, by casting, albeit only from about 1000 CE in South America and then soon afterwards in western Mexico.</p>
<p>In the case of Mesoamerica, the knowledge of bronze was believed to have been carried north from Peru and Ecuador to Mexico by maritime traders. </p>
<p>Clearly, the ancient world, both Old and New, was well connected by lengthy trade routes along which ideas (and in many cases tin) flowed.</p>
<h2>The mix of tin</h2>
<p>The transmission of the technology can also be followed by paying attention to specific aspects of the physical metallurgy involved.</p>
<p>When more than about 15% tin by mass is added to the copper, the resulting alloy becomes rather brittle in its cast form, even if it still has a wonderfully warm golden yellow colour.</p>
<p>Somebody, somewhere, made the remarkable discovery that if such a casting is rapidly quenched from red heat into water (or better, brine), it becomes softer and relatively more ductile and workable.</p>
<p>The quenching heat treatment leaves a very characteristic needle-like microstructure (known as martensite) in the artefact that can be detected by a microscope. This tells an archaeologist that the part has been manufactured by a comparatively complex process, rather than merely cast.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The presence of martensite needles in microsections taken through high-tin bronze artefacts is a sure sign that they have been quenched into water from red heat.</span>
<span class="attribution"><span class="source">Michael Cortie</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>When the tin content is less than about 15%, no martensite forms and nothing remarkable happens on quenching.</p>
<p>The result obtained when heat-treating a high-tin bronze is counterintuitive because, when iron is treated this way, it becomes hard and brittle. The trick to make the bronze tough is so specific that it is most likely this knowledge was transmitted from person to person.</p>
<p>Its transfer across the Old World would have required knowledgeable individuals travelling significant distance to foreign climes. The appearance of these artefacts at far-flung locations across Eurasia and Africa is another sign of ancient globalisation.</p>
<h2>An extra element</h2>
<p>There is one more trick that appears in the ancient bronzes, although this one might have been independently discovered at more than one location.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hydrogen-fuels-rockets-but-what-about-power-for-daily-life-were-getting-closer-112958">Hydrogen fuels rockets, but what about power for daily life? We're getting closer</a>
</strong>
</em>
</p>
<hr>
<p>Some time in the Late Bronze Age or Early Iron Age (around 500 BCE), craftspeople began to add lead to their tin bronze castings. This gives the molten metal extra fluidity, allowing it to flow into fine detail in a mould so that castings with fine details and embossed figures can be made.</p>
<p>As an element, lead is not as shiny or attractive as tin; it is much denser and is found in quite different ores such as galena (lead sulfide). The earliest known cast bronzes with significant controlled additions of lead appear to be from China (500 BCE to 200 CE). Once again, it was clearly a deliberate innovation, and once again it spread rapidly all over Eurasia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=525&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=525&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=525&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=659&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=659&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=659&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Another ancient bronze from Thailand (measure is in centimetres).</span>
<span class="attribution"><span class="source">Courtesy of Dr Supitcha Supansomboon and Assoc Prof Seriwat Saminpanya</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>As more sites such as the ones in eastern Thailand are excavated, and as the database of alloy compositions and dates increases, it will become possible to cast more light on ancient routes of trade, migration and tech transfer. </p>
<p>The presence and usage of tin at these sites will act as a kind of metallurgical DNA, an indicator for ancient cultural and human exchanges.</p>
<hr>
<p><em>If you’re an academic researcher working with a particular element from the periodic table and have an interesting story to tell then why not <a href="https://theconversation.com/au/pitches">get in touch</a>.</em></p><img src="https://counter.theconversation.com/content/114195/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Cortie receives funding from the Australian Research Council.</span></em></p>On its own it’s just tin. But mix it with other elements and it turns into a material that helped shape the ancient world.Michael Cortie, Physics Discipline Leader, University of Technology SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1068992019-01-02T09:12:42Z2019-01-02T09:12:42ZThe periodic table is 150 – but it could have looked very different<figure><img src="https://images.theconversation.com/files/249935/original/file-20181211-76968-1lsh5rp.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Theodor Benfey's spira table (1964).</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/Category:Alternative_forms_of_periodic_table#/media/File:Elementspiral_(polyatomic).svg">DePiep/Wikipedia</a></span></figcaption></figure><p>The <a href="https://theconversation.com/the-periodic-table-from-its-classic-design-to-use-in-popular-culture-52822">periodic table </a> stares down from the walls of just about every chemistry lab. The credit for its creation generally goes to <a href="http://www.rsc.org/education/teachers/resources/periodictable/pre16/develop/mendeleev.htm">Dimitri Mendeleev</a>, a Russian chemist who in 1869 wrote out the known elements (of which there were 63 at the time) on cards and then arranged them in columns and rows according to their chemical and physical properties. To celebrate the 150th anniversary of this pivotal moment in science, the UN has proclaimed 2019 to be the <a href="https://iupac.org/united-nations-proclaims-international-year-periodic-table-chemical-elements/">International year of the Periodic Table</a>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=786&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=786&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=786&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=988&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=988&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249435/original/file-20181207-128205-1xfg95r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=988&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">John Dalton’s element list.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Dalton%27s_Element_List.jpg">Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>But the periodic table didn’t actually start with Mendeleev. Many had tinkered with arranging the elements. Decades before, chemist John Dalton tried to <a href="http://www.sussexvt.k12.de.us/science/the%20history%20of%20the%20world%201500-1899/john%20dalton%27s%20periodic%20tables.htm">create a table</a> as well as some rather interesting symbols for the elements (they didn’t catch on). And just a few years before Mendeleev sat down with his deck of homemade cards, <a href="https://www.britannica.com/biography/John-Newlands">John Newlands</a> also created a table sorting the elements by their properties.</p>
<p>Mendeleev’s genius was in what he left out of his table. He recognised that certain elements were missing, yet to be discovered. So where Dalton, Newlands and others had laid out what was known, Mendeleev left space for the unknown. Even more amazingly, he accurately predicted the properties of the missing elements.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=350&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=350&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=350&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=440&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=440&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249713/original/file-20181210-76959-1jny1g2.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=440&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dimitry Mendeleev’s table complete with missing elements.</span>
<span class="attribution"><span class="source">Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>Notice the question marks in his table above? For example, next to Al (aluminium) there’s space for an unknown metal. Mendeleev foretold it would have an atomic mass of 68, a density of six grams per cubic centimetre and a very low melting point. Six years later <a href="https://www.lindahall.org/paul-emile-lecoq-de-boisbaudran/">Paul Émile Lecoq de Boisbaudran,</a> isolated <a href="http://www.rsc.org/periodic-table/element/31/gallium">gallium</a> and sure enough it slotted right into the gap with an atomic mass of 69.7, a density of 5.9g/cm³ and a melting point so low that <a href="https://www.youtube.com/watch?v=N6ccRvKKwZQ">it becomes liquid in your hand</a>. Mendeleev did the same for <a href="https://www.meta-synthesis.com/webbook/35_pt/pt_database.php?PT_id=303">scandium, germanium</a> and <a href="http://www.rsc.org/periodic-table/element/43/technetium">technetium</a> (which wasn’t discovered until 1937, 30 years after his death).</p>
<p>At first glance Mendeleev’s table doesn’t look much like the one we are familiar with. For one thing, the modern table has a bunch of elements that Mendeleev overlooked (and failed to leave room for), most notably the noble gases (such as helium, neon, argon). And the table is oriented differently to our modern version, with elements we now place together in columns arranged in rows.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=318&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=318&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=318&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=400&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=400&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249442/original/file-20181207-128193-vpgzxa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=400&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Today’s periodic table.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/File:Simple_Periodic_Table_Chart-en.svg">Offnfopt/Wikipedia</a></span>
</figcaption>
</figure>
<p>But once you give Mendeleev’s table a 90-degree turn, the similarity to the modern version becomes apparent. For example, the halogens – fluorine (F), chlorine (Cl), bromine (Br), and Iodine (I) (the J symbol in Mendeleev’s table) – all appear next to one another. Today they are arranged in the table’s 17th column (or group 17 as chemists prefer to call it).</p>
<h2>Period of experimentation</h2>
<p>It may seem a small leap from this to the familiar diagram but, years after Mendeleev’s publications, there was plenty of experimentation with alternative layouts for the elements. Even before the table got its permanent right-angle flip, folks suggested some weird and wonderful twists.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=630&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=630&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=630&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=791&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=791&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249444/original/file-20181207-128187-1dgwvl6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=791&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Heinrich Baumhauer’s spiral.</span>
<span class="attribution"><span class="source">Reprinted (adapted) with permission from Types of graphic classifications of the elements. III. Spiral, helical, and miscellaneous charts, G. N. Quam, Mary Battell Quam. Copyright (1934) American Chemical Society.</span></span>
</figcaption>
</figure>
<p>One particularly striking example is Heinrich <a href="https://www.meta-synthesis.com/webbook/35_pt/JCE_PTs_1934.pdf">Baumhauer’s spiral</a>, published in 1870, with hydrogen at its centre and elements with increasing atomic mass spiralling outwards. The elements that fall on each of the wheel’s spokes share common properties just as those in a column (group) do so in today’s table. There was also Henry Basset’s <a href="http://www.chem.msu.ru/eng/misc/mendeleev/hyper/">rather odd “dumb-bell”</a> formulation of 1892.</p>
<p>Nevertheless, by the beginning of the 20th century, the table had settled down into a familiar horizontal format with the <a href="https://www.meta-synthesis.com/webbook/35_pt/JCE_PTs_1934_medium.pdf">strikingly modern looking version from Alfred Werner</a> in 1905. For the first time, the noble gases appeared in their now familiar position on the far right of the table. Werner also tried to take a leaf out of Mendeleev’s book by leaving gaps, although he rather overdid the guess work with suggestions for elements lighter than hydrogen and another sitting between hydrogen and helium (none of which exist).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=227&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=227&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=227&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=285&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=285&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249445/original/file-20181207-128196-1g58xp9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=285&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Alfred Werner’s modern incarnation.</span>
<span class="attribution"><span class="source">Reprinted (adapted) with permission from Types of graphic classifications of the elements. I. Introduction and short tables, G. N. Quam, Mary Battell Quam. Copyright (1934) American Chemical Society.</span></span>
</figcaption>
</figure>
<p>Despite this rather modern looking table, there was still a bit of rearranging to be done. Particularly influential was <a href="https://link.springer.com/article/10.1007/s10698-008-9062-5">Charles Janet’s</a> version. He took a physicist’s approach to the table and used a newly discovered <a href="https://theconversation.com/explainer-quantum-physics-570">quantum theory</a> to create a layout based on electron configurations. The resulting “<a href="https://www.sciencenews.org/blog/context/old-periodic-table-could-resolve-today%25E2%2580%2599s-element-placement-dispute">left step</a>” table is still preferred by many physicists. Interestingly, Janet also provided space for elements right up to number 120 despite only 92 being known at the time (we’re only at 118 now).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=140&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=140&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=140&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=176&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=176&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249448/original/file-20181207-128187-11i867s.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=176&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Charles Janet’s left-step table.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Charles_Janet">Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Settling on a design</h2>
<p>The modern table is actually <a href="https://www.meta-synthesis.com/webbook/documents/LEACH_Basic_Elemental_Property.pdf">a direct evolution of Janet’s version</a>. The alkali metals (the group topped by lithium) and the alkaline earth metals (topped by beryllium) got shifted from far right to the far left to create a very wide looking (long form) periodic table. The problem with this format is that it doesn’t fit nicely on a page or poster, so largely for aesthetic reasons the f-block elements are usually cut out and deposited below the main table. That’s how we arrived at the table we recognise today.</p>
<p>That’s not to say folks haven’t tinkered with layouts, often as an attempt to highlight correlations between elements that aren’t readily apparent in the conventional table. There are literally hundreds of variations (check out Mark Leach’s <a href="https://www.meta-synthesis.com/webbook/35_pt/pt_database.php">database</a>) with <a href="https://www.meta-synthesis.com/webbook/35_pt/pt_database.php?Button=Spiral+Formulations">spirals</a> and <a href="https://www.meta-synthesis.com/webbook/35_pt/pt_database.php?Button=3D+Formulations">3D versions</a> being particularly popular, not to mention more tongue-in-cheek variants.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/249485/original/file-20181207-128196-ie5nlv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249485/original/file-20181207-128196-ie5nlv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=476&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249485/original/file-20181207-128196-ie5nlv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=476&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249485/original/file-20181207-128196-ie5nlv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=476&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249485/original/file-20181207-128196-ie5nlv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=598&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249485/original/file-20181207-128196-ie5nlv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=598&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249485/original/file-20181207-128196-ie5nlv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=598&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">3D ‘Mendeleev flower’ version of the table.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/Category:Alternative_forms_of_periodic_table">Тимохова Ольга/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>How about my <a href="https://universityofhull.app.box.com/v/elementstubemap">own fusion of two iconic graphics</a>, Mendeleev’s table and Henry Beck’s London Underground map below? </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249481/original/file-20181207-128187-1stsxv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The author’s underground map of the elements.</span>
<span class="attribution"><span class="source">Mark Lorch</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Or the dizzy array of imitations that aim to give a science feel to categorising everything from <a href="http://ecx.images-amazon.com/images/I/81CFIrGYpzL._SL1500_.jpg">beer</a> to <a href="https://ohmy.disney.com/wp-content/uploads/sites/25/2015/03/omd_periodictableofdisney_final.jpg">Disney characters</a>, and my particular favourite “<a href="http://www.crispian.net/PTIR/Nonsense.html">irrational nonsense</a>”. All of which go to show how the periodic table of elements has become the iconic symbol of science.</p><img src="https://counter.theconversation.com/content/106899/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Lorch does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>There have been some rather wacky looking suggestions for arranging the chemical elements.Mark Lorch, Professor of Science Communication and Chemistry, University of HullLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/947002018-05-23T10:39:19Z2018-05-23T10:39:19ZThe Standard Model of particle physics: The absolutely amazing theory of almost everything<figure><img src="https://images.theconversation.com/files/219824/original/file-20180521-14978-36nv6i.jpg?ixlib=rb-1.1.0&rect=174%2C0%2C977%2C649&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">How does our world work on a subatomic level?</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Varsha_ys.jpg">Varsha Y S</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>The Standard Model. What a dull name for the most accurate scientific theory known to human beings.</p>
<p>More than a quarter of the Nobel Prizes in physics of the last century are direct inputs to or direct results of the Standard Model. Yet its name suggests that if you can afford a few extra dollars a month you should buy the upgrade. <a href="https://scholar.google.com/citations?user=eQiX0m4AAAAJ&hl=en&oi=ao">As a theoretical physicist</a>, I’d prefer The Absolutely Amazing Theory of Almost Everything. That’s what the Standard Model really is.</p>
<p>Many recall the excitement among scientists and media over the 2012 <a href="https://home.cern/topics/higgs-boson">discovery of the Higgs boson</a>. But that much-ballyhooed event didn’t come out of the blue – it capped a five-decade undefeated streak for the Standard Model. Every fundamental force but gravity is included in it. Every attempt to overturn it to demonstrate in the laboratory that it must be substantially reworked – and there have been many over the past 50 years – has failed. </p>
<p>In short, the <a href="https://home.cern/about/physics/standard-model">Standard Model</a> answers this question: What is everything made of, and how does it hold together?</p>
<h2>The smallest building blocks</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/219828/original/file-20180521-14991-vlfgkx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">But these elements can be broken down further.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Periodic_table_vectorial.png">Rubén Vera Koster</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>You know, of course, that the world around us is made of molecules, and molecules are made of atoms. Chemist <a href="https://www.famousscientists.org/dmitri-mendeleev/">Dmitri Mendeleev</a> figured out in the 1860s how to organize all atoms – that is, the elements – into the periodic table that you probably studied in middle school. But there are 118 different chemical elements. There’s antimony, arsenic, aluminum, selenium … and 114 more.</p>
<p>Physicists like things simple. We want to boil things down to their essence, a few basic building blocks. Over a hundred chemical elements is not simple. The ancients believed that everything is made of just five elements – <a href="https://en.wikipedia.org/wiki/Classical_element">earth, water, fire, air and aether</a>. Five is much simpler than 118. It’s also wrong. </p>
<p>By 1932, scientists knew that all those atoms are made of just three particles – neutrons, protons and electrons. The neutrons and protons are bound together tightly into the nucleus. The electrons, thousands of times lighter, whirl around the nucleus at speeds approaching that of light. Physicists <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1918/planck-bio.html">Planck</a>, <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1922/bohr-bio.html">Bohr</a>, <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1933/schrodinger-bio.html">Schroedinger</a>, <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1932/heisenberg-bio.html">Heisenberg</a> and friends had invented a new science – <a href="https://en.wikipedia.org/wiki/Quantum_mechanics">quantum mechanics</a> – to explain this motion.</p>
<p>That would have been a satisfying place to stop. Just three particles. Three is even simpler than five. But held together how? The negatively charged electrons and positively charged protons are bound together by <a href="https://en.wikipedia.org/wiki/Electromagnetism">electromagnetism</a>. But the protons are all huddled together in the nucleus and their positive charges should be pushing them powerfully apart. The neutral neutrons can’t help. </p>
<p>What binds these protons and neutrons together? “Divine intervention” a man on a Toronto street corner told me; he had a pamphlet, I could read all about it. But this scenario seemed like a lot of trouble even for a divine being – keeping tabs on every single one of the universe’s 10⁸⁰ protons and neutrons and bending them to its will. </p>
<h2>Expanding the zoo of particles</h2>
<p>Meanwhile, nature cruelly declined to keep its zoo of particles to just three. Really four, because we should count the <a href="https://en.wikipedia.org/wiki/Photon">photon</a>, the particle of light that <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1921/einstein-bio.html">Einstein</a> described. Four grew to five when <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1936/anderson-bio.html">Anderson</a> measured electrons with positive charge – positrons – striking the Earth from outer space. At least <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1933/dirac-bio.html">Dirac</a> had predicted these first anti-matter particles. Five became six when the pion, which <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1949/yukawa-bio.html">Yukawa</a> predicted would hold the nucleus together, was found. </p>
<p>Then came the muon – 200 times heavier than the electron, but otherwise a twin. “Who ordered that?” <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1944/rabi-bio.html">I.I. Rabi</a> quipped. That sums it up. Number seven. Not only not simple, redundant.</p>
<p>By the 1960s there were hundreds of “fundamental” particles. In place of the well-organized periodic table, there were just long lists of baryons (heavy particles like protons and neutrons), mesons (like <a href="https://en.wikipedia.org/wiki/Hideki_Yukawa">Yukawa</a>’s pions) and leptons (light particles like the electron, and the elusive neutrinos) – with no organization and no guiding principles.</p>
<p>Into this breach sidled the Standard Model. It was not an overnight flash of brilliance. No Archimedes leapt out of a bathtub shouting “eureka.” Instead, there was a series of crucial insights by a few key individuals in the mid-1960s that transformed this quagmire into a simple theory, and then five decades of experimental verification and theoretical elaboration. </p>
<p><a href="https://home.cern/about/updates/2014/01/fifty-years-quarks">Quarks</a>. They come in six varieties we call flavors. Like ice cream, except not as tasty. Instead of vanilla, chocolate and so on, we have up, down, strange, charm, bottom and top. In 1964, <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1969/gell-mann-bio.html">Gell-Mann</a> and <a href="https://www.macfound.org/fellows/113/">Zweig</a> taught us the recipes: Mix and match any three quarks to get a baryon. Protons are two ups and a down quark bound together; neutrons are two downs and an up. Choose one quark and one antiquark to get a meson. A pion is an up or a down quark bound to an anti-up or an anti-down. All the material of our daily lives is made of just up and down quarks and anti-quarks and electrons.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=536&fit=crop&dpr=1 600w, https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=536&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=536&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=673&fit=crop&dpr=1 754w, https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=673&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/219958/original/file-20180522-51127-4tx5tr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=673&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Standard Model of elementary particles provides an ingredients list for everything around us.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Standard_Model_From_Fermi_Lab.jpg">Fermi National Accelerator Laboratory</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Simple. Well, simple-ish, because keeping those quarks bound is a feat. They are tied to one another so tightly that you never ever find a quark or anti-quark on its own. The theory of that binding, and the particles called gluons (chuckle) that are responsible, is called <a href="https://en.wikipedia.org/wiki/Quantum_chromodynamics">quantum chromodynamics</a>. It’s a vital piece of the Standard Model, but mathematically difficult, even posing an unsolved problem of basic mathematics. We physicists do our best to calculate with it, but we’re still learning how.</p>
<p>The other aspect of the Standard Model is “<a href="https://doi.org/10.1103/PhysRevLett.19.1264">A Model of Leptons</a>.” That’s the name of the landmark 1967 paper by <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1979/weinberg-bio.html">Steven Weinberg</a> that pulled together quantum mechanics with the vital pieces of knowledge of how particles interact and organized the two into a single theory. It incorporated the familiar electromagnetism, joined it with what physicists called “the weak force” that causes certain radioactive decays, and explained that they were different aspects of the same force. It incorporated <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/2013/higgs-facts.html">the Higgs mechanism</a> for giving mass to fundamental particles. </p>
<p>Since then, the Standard Model has predicted the results of experiment after experiment, including the discovery of several varieties of quarks and of the <a href="https://en.wikipedia.org/wiki/W_and_Z_bosons">W and Z bosons</a> – heavy particles that are for weak interactions what the photon is for electromagnetism. The possibility that <a href="https://en.wikipedia.org/wiki/Neutrino#Mass">neutrinos aren’t massless</a> was overlooked in the 1960s, but slipped easily into the Standard Model in the 1990s, a few decades late to the party.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/219960/original/file-20180522-51095-vverdp.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">3D view of an event recorded at the CERN particle accelerator showing characteristics expected from the decay of the SM Higgs boson to a pair of photons (dashed yellow lines and green towers).</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:3D_view_of_an_event_recorded_with_the_CMS_detector_in_2012_at_a_proton-proton_centre_of_mass_energy_of_8_TeV.png">McCauley, Thomas; Taylor, Lucas; for the CMS Collaboration CERN</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Discovering the Higgs boson in 2012, long predicted by the Standard Model and long sought after, was a thrill but not a surprise. It was yet another crucial victory for the Standard Model over the dark forces that particle physicists have repeatedly warned loomed over the horizon. Concerned that the Standard Model didn’t adequately embody their expectations of simplicity, worried about its mathematical self-consistency, or looking ahead to the eventual necessity to bring the force of gravity into the fold, physicists have made numerous proposals for theories beyond the Standard Model. These bear exciting names like <a href="https://en.wikipedia.org/wiki/Grand_Unified_Theory">Grand Unified Theories</a>, <a href="https://en.wikipedia.org/wiki/Supersymmetry">Supersymmetry</a>, <a href="https://en.wikipedia.org/wiki/Technicolor_(physics)">Technicolor</a>, and <a href="https://en.wikipedia.org/wiki/String_theory">String Theory</a>. </p>
<p>Sadly, at least for their proponents, beyond-the-Standard-Model theories have not yet successfully predicted any new experimental phenomenon or any experimental discrepancy with the Standard Model.</p>
<p>After five decades, far from requiring an upgrade, the Standard Model is <a href="http://artsci.case.edu/smat50/">worthy of celebration</a> as the Absolutely Amazing Theory of Almost Everything.</p><img src="https://counter.theconversation.com/content/94700/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Glenn Starkman receives funding from the Office of Science of the US Department of Energy. He is affiliated with Case Western Reserve University. </span></em></p>A particle physicist explains just what this keystone theory includes. After 50 years, it’s the best we’ve got to answer what everything in the universe is made of and how it all holds together.Glenn Starkman, Distinguished University Professor of Physics, Case Western Reserve UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/939162018-05-02T10:40:36Z2018-05-02T10:40:36ZElements from the stars: The unexpected discovery that upended astrophysics 66 years ago<figure><img src="https://images.theconversation.com/files/217062/original/file-20180501-135840-1g8smw7.png?ixlib=rb-1.1.0&rect=0%2C97%2C952%2C793&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">New heavy nuclei are constantly generated in stars and other astronomical bodies.</span> <span class="attribution"><span class="source">Erin O’Donnell</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Nearly 70 years ago, astronomer Paul Merrill was watching the sky through a telescope at <a href="https://www.mtwilson.edu/">Mount Wilson Observatory</a> in Pasadena, California. As he observed the light coming from a distant star, he saw signatures of the element technetium.</p>
<p>This was completely unexpected. Technetium has no stable forms – it’s what physicists call an <a href="https://en.wikipedia.org/wiki/Synthetic_element">“artificial” element</a>. As Merrill himself put it with a bit of understatement, “<a href="https://doi.org/10.1126/science.115.2992.479">It is surprising to find an unstable element in the stars</a>.”</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=799&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=799&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=799&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1004&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1004&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217074/original/file-20180501-135803-wsicre.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1004&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Paul W. Merrill standing at the spectrograph mounted on the 60-inch telescope at Mount Wilson Observatory.</span>
<span class="attribution"><a class="source" href="http://hdl.huntington.org/cdm/singleitem/collection/p15150coll2/id/1584/rec/11">Observatories of the Carnegie Institution for Science Collection at the Huntington Library, San Marino, California</a></span>
</figcaption>
</figure>
<p>Any technetium present when the star formed should have transformed itself into a different element, such as ruthenium or molybdenum, a very long time ago. As an artificial element, someone must have recently created the technetium Merrill spotted. But who or what could have done that in this star?</p>
<p>On May 2, 1952, Merrill reported his <a href="https://doi.org/10.1126/science.115.2992.479">discovery in the journal Science</a>. Among the three interpretations offered by Merrill was the answer: Stars create heavy elements! Not only had Merrill explained a puzzling observation, he had also opened the door to understand our cosmic origins. Not many discoveries in science completely change our view of the world – but this one did. The newly revealed picture of the universe was simply mind-blowing, and the repercussions of this discovery are still driving nuclear science research today.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=414&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=414&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=414&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217099/original/file-20180501-135848-hyzcan.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Technetium nuclei are transformed into Ruthenium or Molybdenum within a few million years – so if you spot them now, they can’t be left from the Big Bang billions of years ago.</span>
<span class="attribution"><span class="source">Erin O’Donnell, Michigan State University</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Where do elements come from?</h2>
<p>In the early 1950s, it was still unclear how the elements that make up our universe, our solar system, even our human bodies, were created. Initially, the most popular scenario was that they were all made in the Big Bang.</p>
<p>First alternative scenarios were developed by renowned scientists of the time, like <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1967/bethe-facts.html">Hans Bethe</a> (Nobel Prize in Physics, 1967), <a href="https://www.atomicheritage.org/profile/carl-friedrich-von-weizs%C3%A4cker">Carl Friedrich von Weizsäcker</a> (Max-Plank Medal, 1957), and <a href="https://www.britannica.com/biography/Fred-Hoyle">Fred Hoyle</a> (Royal Medal, 1974). But no one really had come up with a convincing theory for the origin of the elements – until Paul Merrill’s observation. </p>
<p>Merrill’s discovery marked the birth of a completely new field: stellar nucleosynthesis. It’s the study of how the elements, or more accurately their atomic nuclei, are synthesized in stars. It didn’t take long for scientists to start trying to figure out exactly what the process of element synthesis in stars entailed. This is where nuclear physics had to come into play, to help explain Merrill’s amazing observation.</p>
<h2>Fusing nuclei in the heart of a star</h2>
<p>Brick by brick, element by element, nuclear processes in stars take the abundant hydrogen atoms and build heavier elements, from helium and carbon all the way to technetium and beyond. </p>
<p>Four prominent nuclear (astro)physicists of the time worked together, and in 1957 published the “<a href="https://journals.aps.org/rmp/pdf/10.1103/RevModPhys.29.547">Synthesis of the Elements in Stars</a>”: <a href="https://www.britannica.com/biography/Margaret-Burbidge">Margaret Burbidge</a> (Albert Einstein World Award of Science, 1988), <a href="http://www.phys-astro.sonoma.edu/brucemedalists/burbidgeg/index.html">Geoffrey Burbidge</a> (Bruce Medal, 1999), <a href="https://www.nobelprize.org/nobel_prizes/physics/laureates/1983/fowler-facts.html">William Fowler</a> (Nobel Prize in Physics, 1983), and <a href="https://www.britannica.com/biography/Fred-Hoyle">Fred Hoyle</a> (Royal Medal, 1974). The publication, known as B2FH, still remains a reference for describing astrophysical processes in stars. <a href="http://www.nasonline.org/publications/biographical-memoirs/memoir-pdfs/cameron-a-g-w.pdf">Al Cameron</a> (Hans Bethe Prize, 2006) in the same year independently arrived at the same theory in his paper “<a href="https://doi.org/10.1086/127051">Nuclear Reactions in Stars and Nucleogenesis</a>.”</p>
<p>Here’s the story they put together.</p>
<p>Stars are heavy. You’d think they would completely collapse in upon themselves because of their own gravity – but they don’t. What prevents this collapse is nuclear fusion reactions happening at the star’s center.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=855&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=855&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=855&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1074&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1074&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217106/original/file-20180501-135810-6g81mr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1074&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">When atomic nuclei collide, they sometimes fuse, forming new elements.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:FusionintheSun.svg">Borb</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Within a star are billions and billions of atoms. They’re zooming all around, sometimes colliding with one another. Initially the star is too cold, and when atoms’ nuclei collide they simply bounce off each other. As the star compresses because of its gravity, though, the temperature at its center increases. In such hot conditions, now when nuclei run into each other they have enough energy to merge together. This is what physicists call a <a href="https://en.wikipedia.org/wiki/Nuclear_fusion">nuclear fusion reaction</a>.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=642&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=642&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=642&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=807&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=807&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217066/original/file-20180501-135817-rqu0m6.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=807&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fusion reactions happen in different parts of a star. Technetium is created in the shell.</span>
<span class="attribution"><a class="source" href="http://www.eso.org/public/images/eso0729a/">ESO</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>These nuclear reactions serve two purposes.</p>
<p>First, they release energy that heats the star, providing the outward pressure that prevents its gravitational collapse and keeps the star in balance for billions of years. Second, they <a href="http://www.jinaweb.org/movies/pp_chain.html">fuse light elements into heavier ones</a>. And slowly, starting with hydrogen and helium, stars will make the technetium that Merrill observed, the calcium in our bones and the gold in our jewelry.</p>
<p>Many different nuclear reactions are responsible for making all this happen. And they’re extremely difficult to study in the laboratory because nuclei are hard to fuse. That’s why, for more than six decades, <a href="https://doi.org/10.1007/s00016-018-0216-0">nuclear physicists have continued to work</a> to get a handle on the nuclear reactions that drive the stars.</p>
<h2>Astrophysicists still untangling element origins</h2>
<p>Today there are many more ways to observe the signatures of element creation throughout the universe.</p>
<p>Very old stars record the composition of the universe way back at the time of their formation. As more and more stars of varying ages are found, their compositions begin to tell the <a href="https://doi.org/10.1063/PT.3.3815">story of element synthesis in our galaxy</a>, from its formation shortly after the Big Bang to today.</p>
<p>And the more researchers learn, the more complex the picture gets. In the last decade, observations provided evidence for a much broader range of element-creating processes than anticipated. For some of these processes, we do not even know yet in what kind of stars or stellar explosions they occur. But astrophysicists think all these stellar events have contributed their characteristic mix of elements into the swirling dust cloud that ultimately became our solar system.</p>
<p>The most recent example comes from a <a href="https://theconversation.com/cosmic-alchemy-colliding-neutron-stars-show-us-how-the-universe-creates-gold-86104">neutron-star merger event</a> tracked <a href="https://theconversation.com/ligo-announcement-vaults-astronomy-out-of-its-silent-movie-era-into-the-talkies-85727">by gravitational and electromagnetic observatories</a> around the world. This observation demonstrates that even merging neutron stars make a large contribution to the production of heavy elements in the universe – in this case the so-called Lanthanides that include elements such as Terbium, Neodynium and the Dysprosium used in cellphones. And just like at the time of Merrill’s discovery, nuclear scientists around the world are scrambling, working overtime at their accelerators, to figure out what nuclear reactions could possibly explain all these new observations.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=380&fit=crop&dpr=1 600w, https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=380&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=380&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=477&fit=crop&dpr=1 754w, https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=477&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/217108/original/file-20180501-135825-hhntgj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=477&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Modern nucleosynthesis experiments, like those of the authors, are run on nuclear physics equipment including particle accelerators.</span>
<span class="attribution"><a class="source" href="http://nscl.msu.edu/">National Superconducting Cyclotron Laboratory</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Discoveries that change our view of the world don’t happen every day. But when they do, they can provide more questions than answers. It takes a lot of additional work to find all the pieces of the new scientific jigsaw puzzle, put them together step by step and eventually arrive at a new understanding. Advanced astronomical observations with modern telescopes continue to reveal more and more secrets hidden in distant stars. State-of-the-art accelerator facilities study the nuclear reactions that create elements in stars. And sophisticated computer models put it all together, trying to recreate the parts of the universe we see, while reaching out toward the ones that are still hiding until the next major discovery.</p><img src="https://counter.theconversation.com/content/93916/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Artemis Spyrou receives funding from the National Science Foundation and the Department of Energy/National Nuclear Security Administration. </span></em></p><p class="fine-print"><em><span>Hendrik Schatz receives funding from National Science Foundation and Department of Energy Office of Science.</span></em></p>People long assumed all the elements we see now were created during the Big Bang. But on May 2, 1952, an astronomer reported spotting new elements coming from an old star and changed our origin story.Artemis Spyrou, Associate Professor of Nuclear Physics, Michigan State UniversityHendrik Schatz, University Distinguished Professor of Nuclear Astrophysics, Michigan State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/876212018-01-28T18:08:12Z2018-01-28T18:08:12ZBiomining the elements of the future<figure><img src="https://images.theconversation.com/files/203145/original/file-20180124-72597-1twk9y1.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Joey Kyber/Pixels</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Biomining is the kind of technique promised by science fiction: a vast tank filled with microorganisms that leach metal from ore, old mobile phones and hard drives. </p>
<p>It sounds futuristic, but it’s currently used to produce about 5% of the world’s gold and <a href="http://www.bbc.com/news/technology-17406375">20% of the world’s copper</a>. It’s also used to a lesser extent to extract nickel, zinc, cobalt and rare earth elements. But perhaps it’s most exciting potential is extracting rare earth elements, which are crucial in everything from mobile phones to renewable energy technology.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/will-rare-earth-elements-power-our-clean-energy-future-2433">Will rare earth elements power our clean energy future?</a>
</strong>
</em>
</p>
<hr>
<p>The Mary Kathleen mine, an exhausted uranium mine in northwest Queensland, contains an estimated A$4 billion in rare earth elements. Biomining offers a cost-effective and environmentally friendly option for getting it out.</p>
<p>Biomining is so versatile that it can be used on other planetary bodies. <a href="https://www.nature.com/articles/ismej201146">Bioleaching studies</a> on the international space station have shown microorganisms from extreme environments on Earth can leach a large variety of important minerals and metals from rocks when exposed to the cold, heat, radiation and vacuum of space. </p>
<p><a href="https://www.scientificamerican.com/article/space-colonists-could-use-bacteria/">Some scientists even believe</a> we cannot colonise other planets without the help of biomining technologies.</p>
<h2>How does it work?</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/196063/original/file-20171123-6051-1lh1cwt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/196063/original/file-20171123-6051-1lh1cwt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/196063/original/file-20171123-6051-1lh1cwt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/196063/original/file-20171123-6051-1lh1cwt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/196063/original/file-20171123-6051-1lh1cwt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/196063/original/file-20171123-6051-1lh1cwt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/196063/original/file-20171123-6051-1lh1cwt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Microorganisms in tanks leach the minerals from any source material.</span>
<span class="attribution"><span class="source">Courtesy of Pacific Northwest National Laboratory.</span></span>
</figcaption>
</figure>
<p>Biomining takes place within large, closed, stirred-tank reactors (bioreactors). These devices generally contain water, microorganisms (bacteria, archaea, or fungi), ore material, and a source of energy for the microbes.</p>
<p>The source of energy required depends on the specific microbe necessary for the job. For example, gold and copper are biologically “leached” from sulfidic ores using microorganisms that can derive energy from inorganic sources, via the oxidation of sulfur and iron. </p>
<p>However, rare earth elements are bioleached from non-sulfidic ores using microorganisms that require an organic carbon source, because these ores do not contain a usable energy source. In this case, sugars are added to allow the microbes to grow.</p>
<p>All living organisms need metals to carry out basic enzyme reactions. Humans get their metals from the trace concentrations in their food. Microbes, however, obtain metals by dissolving them from the minerals in their environment. They do this by producing organic acids and metal-binding compounds. Scientists exploit these traits by mixing microbes in solution with ores and collecting the metal as it floats to the top.</p>
<p>The temperature, sugars, the rate at which the tank is stirred, acidity, carbon dioxide and oxygen levels all need to be monitored and fine-tuned to provide optimal working conditions</p>
<h2>The benefits of biomining</h2>
<p>Traditional mining methods require harsh chemicals, lots of energy and produce many pollutants. In contrast, biomining uses little energy and produces few microbial by-products such as organic acids and gases.</p>
<p>Because it’s cheap and simple, biomining can effectively exploit low grade sources of metals (such as mine tailings) that would otherwise be uneconomical using traditional methods. </p>
<p>Countries are increasingly turning to biomining such as Finland, Chile and Uganda. Chile has exhausted much of its copper rich ores and now utilises biomining, while Uganda has been extracting cobalt from copper mine tailings for over a decade.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/politically-charged-do-you-know-where-your-batteries-come-from-80886">Politically charged: do you know where your batteries come from?</a>
</strong>
</em>
</p>
<hr>
<h2>Why do we need rare earth elements?</h2>
<p>The rare earth elements include the group of 15 lanthanides near the bottom of the periodic table, plus scandium and yttrium. They are widely used in just about all electronics and are increasingly sought after by the electric vehicle and renewable energy industries.</p>
<p>The unique atomic properties of these elements make them useful as magnets and phosphors. They’re used as strong lightweight magnets in electric vehicles, wind turbines, hard disc drives, medical equipment and as phosphors in energy efficiency lighting and in the LEDs of mobile phones, televisions and laptops.</p>
<p>Despite their name, rare earth elements are not rare and some are in fact more abundant than copper, nickel and lead in the Earth’s crust. However, unlike these primary metals which form ores (a naturally occurring mineral or rock from which a useful substance can be easily extracted), rare earth elements are widely dispersed. Thus to be economically feasible they are generally mined as secondary products alongside primary metals such as iron and copper.</p>
<p>Over 90% of the world’s rare earth elements come from China where production monopolies, trade restrictions and illegal mining have caused prices to <a href="https://ecat.ga.gov.au/geonetwork/srv/eng/search#!a2fa6006-945e-363d-e044-00144fdd4fa6">fluctuate dramatically</a> over the years. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/196062/original/file-20171123-6020-4116vp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/196062/original/file-20171123-6020-4116vp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=304&fit=crop&dpr=1 600w, https://images.theconversation.com/files/196062/original/file-20171123-6020-4116vp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=304&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/196062/original/file-20171123-6020-4116vp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=304&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/196062/original/file-20171123-6020-4116vp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=382&fit=crop&dpr=1 754w, https://images.theconversation.com/files/196062/original/file-20171123-6020-4116vp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=382&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/196062/original/file-20171123-6020-4116vp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=382&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Most renewable energy technologies depend on rare earth metals.</span>
<span class="attribution"><span class="source">Pixabay</span></span>
</figcaption>
</figure>
<p>Reports from the <a href="https://www.energy.gov/epsa/downloads/2011-critical-materials-strategy">US Department of Energy</a>, <a href="http://ec.europa.eu/DocsRoom/documents/10010/attachments/1/translations">European Union</a>, and the <a href="http://www.dtic.mil/docs/citations/ADA580128">US intelligence commission</a> have labelled several rare earth elements as critical materials, based on their importance to clean energy, high supply risk, and lack of substitutes. </p>
<p>These reports encourage research and development into alternative mining methods such as biomining as a potential mitigation strategy.</p>
<p>Heeding these calls, laboratories in <a href="https://link.springer.com/article/10.1007/s00449-017-1757-3">Curtin</a>, and <a href="http://onlinelibrary.wiley.com/doi/10.1002/bit.25823/full">Berkeley</a> Universities have used microorganisms to dissolve common rare-earth-element-bearing minerals. These pilot scale studies have shown promising results, with extraction rates growing closer to those of conventional mining methods.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-how-do-scientists-work-out-how-old-the-earth-is-90391">Curious Kids: How do scientists work out how old the Earth is?</a>
</strong>
</em>
</p>
<hr>
<p>Because most electronics have a notoriously short lifespan and poor recyclability, laboratories are experimenting with “urban” biomining. For example, bioleaching studies have seen success in <a href="http://www.sciencedirect.com/science/article/pii/S0304386X16305473">extracting rare earth elements from the phosphor powder</a> lining fluorescent globes, and the use of microorganisms to recycle rare earth elements from electronic wastes such as <a href="http://pubs.acs.org/doi/abs/10.1021/acs.inorgchem.6b00919">hard drive magnets</a>.</p>
<p>The rare earth elements are critical for the future of our technology. Biomining offers a way to obtain these valuable resources in a way that is both environmentally sustainable and economically feasible.</p>
<p><br></p>
<hr>
<p><em>The author would like to acknowledge co-supervisor Dr Jillian Banfield (Banfield Laboratory, University of California, Berkeley) and principal supervisor and co-author Dr John Moreau (Geomicrobiology Lab Leader, School of Earth Sciences, University of Melbourne).</em></p><img src="https://counter.theconversation.com/content/87621/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marcos Voutsinos does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Fill a tank with water, sugar, and old mobile phones. Add bacteria and stir. Result? Rare earth metals. This is biomining, and it’s the way of the future.Marcos Voutsinos, PhD Candidate, Geomicrobiology, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/903912018-01-23T19:12:29Z2018-01-23T19:12:29ZCurious Kids: How do scientists work out how old the Earth is?<figure><img src="https://images.theconversation.com/files/202744/original/file-20180122-110097-12vj03h.png?ixlib=rb-1.1.0&rect=0%2C0%2C2995%2C1320&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">It turns out that the world is about 4,600,000,000 years old. That's 4.6 billion years. That's pretty old!</span> <span class="attribution"><span class="source">Marcella Cheng/The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p><em>This is an article from <a href="https://theconversation.com/au/topics/curious-kids-36782">Curious Kids</a>, a series for children. The Conversation is asking kids to send in questions they’d like an expert to answer. All questions are welcome – serious, weird or wacky!</em> </p>
<hr>
<blockquote>
<p><strong>How do scientists work out how old the Earth is? Leo, age 5, Geelong West.</strong></p>
</blockquote>
<p>Well, Leo, the world is actually like a big clock. We just need to know how to read the clock. To do that, we have to think about what the world is made of. </p>
<p>The world, and everything in it, is actually made of something very small called “elements”. These are the tiny, tiny building blocks of everything. You might have heard the names of some elements before. Gold is an element, and so is silver. There are lots of other elements too, with strange names like krypton and selenium and plutonium. There are about 118 different elements on Earth that we know about so far.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-what-is-radiocarbon-dating-and-how-does-it-work-9690">Explainer: what is radiocarbon dating and how does it work?</a>
</strong>
</em>
</p>
<hr>
<p>Most of these elements don’t change and stay the way they are forever. Scientists call these ones “stable” elements. </p>
<p>But there is a second sort of element that actually changes into something else over time. These aren’t as common, but they are in everything. They’re called “unstable” or “radioactive” elements.</p>
<p>Imagine that - some part of you is actually changing into something else! But don’t worry, most of these change over a very, very long time. Some take billions of years to do any really serious changing. </p>
<p>Your teeth have an element called potassium that is one of these changing elements. Your TV, computer, the soil in your garden – everything, really – has some of these changing elements. The changing process is called “radioactive decay”.</p>
<p>As you might have guessed, rocks also have these unstable elements in them. And we’ve measured out how long it takes for one of these elements to change into another one. </p>
<p>For example, if we had some stuff that contained an unstable element called <sup>14</sup>C (to say out loud, this is “carbon 14”), we know it takes about 5,730 years for about half of all the <sup>14</sup>C in our sample to change into another element called <sup>14</sup>N (pronounced as “nitrogen 14”).</p>
<p>Knowing how fast these elements change from one thing into another thing gives us a very big clue about how old the Earth is. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/202758/original/file-20180122-110100-1uen2yg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Scientists using the same techniques to work out how old fossils are.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/skippy/452231025/in/photolist-FXNwD-brVUa-9TYo4-foH1Sj-7yC3NV-LyGgG-oH9Hbw-7qGxb1-7BTRZe-3VwGHj-6rcG8U-qEwTLj-aH4QYR-6rcMy9-nGUwUy-k6rwa1-xBLms1-VsqnT7-adHvfz-bs4aEL-UkFeMr-7gXqBj-pmVKXa-22s4SY3-TzTWU5-WetkBY-yYbuwy-7gXokN-prE9br-bi7KjT-5qFrF3-9Dggzr-TUNEQ3-5cgiEa-7shDR8-VApJyE-aJcsdV-VstT2X-9keehg-aELxKE-7aU1eK-djmV9Z-4xkaao-VstTMe-2p8Yhx-4xkaty-a8zjJ7-jdzSh5-4n1mdj-4oyRma">Flickr/Scott</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-do-bees-ever-accidentally-sting-other-bees-82818">Curious Kids: Do bees ever accidentally sting other bees?</a>
</strong>
</em>
</p>
<hr>
<p>So how do we measure how old the Earth is? </p>
<p>Well, first we measure how much of the unstable elements are still left in the rocks of the Earth - these are the elements that haven’t changed yet, but <em>will</em> change over time because we know they’re unstable. </p>
<p>Then we measure the amount of the element they change <em>into</em>. </p>
<p>Once we know this, and we know how long the change takes, we can work out how old the world is! </p>
<p>It turns out that the world is about 4,600,000,000 years old. That’s 4.6 billion years. That’s pretty old!</p>
<hr>
<p><em>Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. You can:</em></p>
<p><em>* Email your question to curiouskids@theconversation.edu.au
<br>
* Tell us on <a href="https://twitter.com/ConversationEDU">Twitter</a> by tagging <a href="https://twitter.com/ConversationEDU">@ConversationEDU</a> with the hashtag #curiouskids, or
<br>
* Tell us on <a href="http://www.facebook.com/conversationEDU">Facebook</a></em></p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><em>Please tell us your name, age and which city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We won’t be able to answer every question but we will do our best.</em></p><img src="https://counter.theconversation.com/content/90391/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alan Collins receives funding from the Australian Research Council</span></em></p>The world is made of tiny building blocks called ‘elements’. Scientists have worked out how fast some elements change into other elements. That gives us a very big clue about how old the Earth is.Alan Collins, Professor of Geology, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/900702018-01-22T17:15:27Z2018-01-22T17:15:27ZHow comet dust has enabled us to trace the history of the Solar System<figure><img src="https://images.theconversation.com/files/201810/original/file-20180112-101514-o1dufb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The comet 67P/Churyumov-Gerasimenko, seen up close.</span> <span class="attribution"><a class="source" href="http://www.esa.int/spaceinimages/Images/2016/11/Rosetta_comet_close-ups">ESA/Rosetta/NavCam</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>We are not used to considering dust as a valuable material – unless it comes from space. And more precisely, from the comet 67P/Churyumov-Gerasimenko. An analysis of its dust has provided valuable information about this celestial object, and, more generally, on the history of the Solar System.</p>
<p>Using the <a href="http://sci.esa.int/rosetta/35061-instruments/?fbodylongid=1638">COSIMA instrument</a> aboard the European space probe Rosetta, a scientific team scrutinised the comet <a href="http://sci.esa.int/rosetta/14615-comet-67p/">67P/Churyumov-Gerasimenko</a> (67P) in great detail from August 2014 to September 2016. They were interested in the dust particles ejected from the comet’s nucleus and captured by the spacecraft, and COSIMA made it possible to study their composition. The results of their research were published in <a href="https://academic.oup.com/mnras/article/469/Suppl_2/S712/4670835">December 2017</a> by the Royal Astronomical Society.</p>
<p>The study indicates that, on average, half of the mass of each dust particle consists of carbonaceous material with a mainly <a href="https://en.oxforddictionaries.com/definition/macromolecule">macromolecular</a> organic structure; the other half being mostly composed of non-hydrated silicate minerals. How is this result important or interesting? What does it imply? Was it expected by scientists or is it a total break pre-existing theories?</p>
<p>Thanks to Rosetta and its instruments, we have been able to get a better idea of what 67P is composed. This is particularly true for the gases in its atmosphere, thanks to the <a href="http://sci.esa.int/rosetta/35061-instruments/?fbodylongid=1650">ROSINA</a> instrument. During the comet’s journey around the Sun, it continuously releases gases and dust that form a faint halo. This phenomenon is explained by the sublimation of ices that are embedded within the nucleus of the comet – they directly change from the solid to the gaseous state. As the gas escapes into the comet’s atmosphere, it bring with it small dust particles. ROSINA has characterised and quantified the gases: it’s made of water vapour, carbon dioxide, carbon monoxide, molecular oxygen and a multitude of small organic molecules mainly made of carbon, hydrogen, nitrogen and oxygen atoms.</p>
<p>Other instruments, such as on-board cameras and the <a href="http://virtis-rosetta.lesia.obspm.fr/VIRTIS-the-instrument.html">VIRTIS</a> imaging spectrometer, studied the surface of 67P. Its structures are complex: cliffs, faults, landslides, pits and more. But above all, the comet surface is very dark and has little ice. The fact that it is so dark is possibly due to a high organic carbon content. Given that the ices and gases represent only a small fraction of the total cometary matter, the researchers rely on, among other things, the analysis of the dust grains released by the comet to learn more about the makeup of the comet’s nucleus. This dust is representative of the comet’s non-volatile composition, and the study of the dust’s chemical characteristics will reflect those of the comet’s nucleus.</p>
<h2>35,000 particles collected</h2>
<p>The COSIMA instrument is a kind of physico-chemical mini-laboratory, whose function was to collect dust particles released by the comet 67P, image them and then measure their chemical characteristics using a surface analysis method called “time-of-flight secondary ion mass spectrometry” (TOF-SIMS). During the two years spent orbiting the comet, data collection was more successful than dared hoped for by the researchers and engineers who designed the instrument about 20 years ago. Indeed, COSIMA has collected more than 35,000 particles that are up to 1 millimetre in diameter. We had expected many fewer and infinitely smaller dust grains.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/201167/original/file-20180108-83574-lhhcyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/201167/original/file-20180108-83574-lhhcyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=294&fit=crop&dpr=1 600w, https://images.theconversation.com/files/201167/original/file-20180108-83574-lhhcyu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=294&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/201167/original/file-20180108-83574-lhhcyu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=294&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/201167/original/file-20180108-83574-lhhcyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=370&fit=crop&dpr=1 754w, https://images.theconversation.com/files/201167/original/file-20180108-83574-lhhcyu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=370&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/201167/original/file-20180108-83574-lhhcyu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=370&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">On the left, the surface of the cometary nucleus seen by the Rosetta probe. Condensed ice beneath the surface sublimes from the depths of the comet when it is warmed up as the comet approaches the Sun. The escaping gas entrains small dust particles that can be collected and analysed by the instruments of the Rosetta probe. On the right, a collecting target (1 cm x 1 cm) of the COSIMA instrument showing tiny fragments of the nucleus, up to a millimetre in size, that have impacted it. All these dust particles consist of an intimate mixture of 50/50 (by mass) of silicate minerals and organic material.</span>
<span class="attribution"><span class="source">Left, ESA/Rosetta/MPS for OSIRIS Team; right, ESA/Rosetta/MPS for COSIMA Team.</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The analysis and scientific interpretation of the mass spectrometric measurements made on a fraction of the particles collected (about 250) was long and challenging. The ultra-porosity of the dust, collected almost intact after ejection from the comet’s surface, has few analogues in our laboratories and the mastery of the TOF-SIMS technique, already complicated in the laboratory, had proved to be almost heroic when conducted remotely in space.</p>
<p>From these measurements, it was possible to deduce the dust particles’ main constituent elements (oxygen, carbon, silicon, iron, magnesium, sodium, nitrogen, aluminium, calcium…), as well as some information on the chemical nature of some components. From these data, the team showed that each dust particle (size ranging from ~0.05 to 1 mm in diameter) contained, on average, about 50% by mass of organic carbonaceous material. This material was mainly macromolecular, meaning that it was made of large structures put together in a totally disordered and complex fashion; the other half of the mass is mainly composed of non-hydrated silicates minerals.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/202873/original/file-20180122-182965-s6lb4b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/202873/original/file-20180122-182965-s6lb4b.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=168&fit=crop&dpr=1 600w, https://images.theconversation.com/files/202873/original/file-20180122-182965-s6lb4b.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=168&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/202873/original/file-20180122-182965-s6lb4b.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=168&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/202873/original/file-20180122-182965-s6lb4b.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=212&fit=crop&dpr=1 754w, https://images.theconversation.com/files/202873/original/file-20180122-182965-s6lb4b.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=212&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/202873/original/file-20180122-182965-s6lb4b.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=212&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Left: the average elemental composition of the dust particles of comet 67P. Right: the average mass distribution of minerals and organic material in the dust.</span>
<span class="attribution"><span class="source">ESA/Rosetta/MPS for COSIMA Team.</span></span>
</figcaption>
</figure>
<p>According to the measurements, this dust composition is independent of the particle collection date. In other words, on average, there is no difference in composition between the dust ejected by the comet before, during or after its <a href="https://www.merriam-webster.com/dictionary/perihelion">perihelion</a>, which is when, in August 2015, 67P made its closest approach to the Sun and where its activity was the most intense. The composition of cometary dust is also not dependent on their size or morphology – “fluffy aggregates” or more “compact grains”. The analysed particles are small fragments of the nucleus, coming from its surface as well as pits that sink into the depths of the comet. Therefore, the average composition determined by COSIMA most likely reflects the overall volatile-free composition of 67P’s nucleus. Most of the cometary matter is thus formed by this intimate mixture of 50-50 by weight of minerals and solid carbonaceous material.</p>
<h2>A primitive material</h2>
<p>These results, as well as those obtained 30 years ago during the flyby of comet Halley by the <a href="https://motherboard.vice.com/en_us/article/nz7zz8/happy-anniversary-giotto-the-probe-that-flew-by-halleys-comet-30-years-ago">Giotto</a> and <a href="https://link.springer.com/article/10.1134/S0038094612070106">Vega</a> probes, prove that comets are among the most carbon-rich Solar System objects. Experts suspected this, but this is finally a direct experimental proof. The high value of the abundance ratio between carbon and silicon measured by COSIMA is very close to the abundance ratio of these elements measured in the Sun’s <a href="https://www.merriam-webster.com/dictionary/photosphere">photosphere</a>. Moreover, the silicates contained in 67P dust do not show any notable signs of alteration by liquid water. These two observations are an important proof of the primitive character of this cometary substance. It means that this material has hardly been modified since the comet’s formation, unlike most other objects in the Solar System. Studying it takes us back to the very beginning of the Solar System, nearly 4.5 billion years ago.</p>
<p>The COSIMA measurements, combined with the observations of the other Rosetta instruments, indicate that most of the cometary carbonaceous material is not found in ices and gases, but in dust, in this non-volatile macromolecular form. This result is in line with laboratory analyses of other extra-terrestrial materials that have been collected on Earth – meteorites, micrometeorites and interplanetary dust particles. With these, however, the original object from which these materials originated is rarely known. And above all, heating during the atmospheric entry alters and modifies, at least in part, their carbonaceous components. </p>
<p>COSIMA’s <em>in situ</em> measurements and its collection of dust at low speeds (a few metres per second, the pace of someone jogging) have made it possible to totally preserve the chemical information. Thus, it is possible to say today that if comets like 67P played a role in the appearance of life on Earth, especially by bringing carbon-rich material, it would have been this complex macromolecular component that dominated what was delivered.</p><img src="https://counter.theconversation.com/content/90070/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Les auteurs ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'ont déclaré aucune autre affiliation que leur organisme de recherche.</span></em></p>Dust can be instructive. The analysis of those collected around the comet 67P/Churyumov-Gerasimenko provided new information on the history of the solar system.Donia Baklouti, Astrochimiste, Maître de Conférences à l’Institut d’Astrophysique Spatiale (IAS), Université Paris-SaclayAnaïs Bardyn, Astrochimiste, post-doctorante au Department of Terrestrial Magnetism (DTM), Carnegie ScienceHervé Cottin, Astrochimiste, Professeur au Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), Université Paris-Est Créteil Val de Marne (UPEC)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/888802017-12-17T17:24:39Z2017-12-17T17:24:39ZPiercing the mystery of the cosmic origins of gold<figure><img src="https://images.theconversation.com/files/198289/original/file-20171208-11325-yh5lap.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Twinkle, twinkle, little star...</span> <span class="attribution"><span class="source">Prawny/Pixabay</span></span></figcaption></figure><p>Where does gold, the precious metal coveted by mortals through the ages, come from? How, where and when was it produced? Last August, a single astrophysical observation finally gave us the key to answer these questions. The <a href="http://public.virgo-gw.eu/gw170817_papers/">results of this research</a> were published on October 16, 2017.</p>
<p>Gold pre-exists the formation of Earth: this is what differentiates it from, for example, diamond. However valuable it may be, this precious stone is born out of mere carbon, whose atomic structure is modified by enormous pressure from the earth’s crust. Gold is totally different – the strongest forces in the earth’s mantle are unable to change the composition of its atomic nucleus. Too bad for the <a href="https://en.wikipedia.org/wiki/Alchemy">alchemists</a> who dreamed of transforming lead into gold.</p>
<p>Yet there is gold on Earth, both in its deep core, where it has migrated together with heavy elements such as lead or silver, and in the planet’s crust, which is where we extract this precious metal. While the gold in the core was already there at the formation of our planet, that in the crust is mostly extraterrestrial and arrived after the formation of Earth. It was brought by a gigantic meteor shower that bombarded the Earth (and the Moon) about 3.8 billion years ago.</p>
<h2>Formation of heavy elements</h2>
<p>How gold is produced in the universe? The elements heavier than iron, including gold, are partially produced by the <em>s</em> process during the ultimate evolution phases of the stars. It is a slow process (<em>s</em> stands for slow) that operates in the core of what are referred to as <a href="https://en.wikipedia.org/wiki/Asymptotic_giant_branch">AGB</a> stars – those of low and intermediate mass (less than 10 solar masses) that can produce chemical elements up to polonium. The other half of the heavy elements is produced by the <em>r</em> process (<em>r</em> stands for rapid). But the site where this nucleo-synthesis process takes place has long remained a mystery.</p>
<p>To understand the discovery enabled by the August 17, 2017, observation, we need to understand the scientific <em>status quo</em> that existed beforehand. For about 50 years, the dominant assumption among the scientific community was that the <em>r</em> process took place during the final explosion of massive stars (specialists speak of a core collapse <a href="https://en.wikipedia.org/wiki/Supernova">supernova</a>). Indeed, the formation of light elements (those up to iron) implies nuclear reactions that ensure the stability of the stars by counteracting contraction induced by gravity. For heavier elements – those from iron and beyond – it is necessary to add energy or to take very specific paths, such as the <em>s</em> and <em>r</em> processes. Researchers believed that the <em>r</em> process could occur in ejected matter from the explosion of massive stars, capturing a part of the released energy and participating to the dissemination of material in the interstellar medium. </p>
<p>Despite the simplicity of this explanation, numerical modelling of supernovae has proved extremely complicated. After 50 years of efforts, researchers have just begun to understand its mechanism. Most of these simulations do unfortunately not provide the physical conditions for the <em>r</em> process.</p>
<p>These conditions are however quite simple: you need a lot of neutrons and a really warm environment.</p>
<h2>Fusion of neutron stars</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=578&fit=crop&dpr=1 600w, https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=578&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=578&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=726&fit=crop&dpr=1 754w, https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=726&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/198647/original/file-20171211-9396-1b4j164.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=726&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Two ounces of gold … from outer space.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:2oz_gold_Engelhard.JPG">Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>In the last decade or so, some researchers have begun to seriously investigate an alternative scenario of the heavy-element production site. They focused their attention on neutron stars. As befits their name, they constitute a gigantic reservoir of neutrons, which are released occasionally. The strongest of these releases occurs during their merging, in a binary system, also called <a href="https://en.wikipedia.org/wiki/Kilonova">kilonova</a>. There are several signatures of this phenomenon that luckily were seen on August 17: a gravitational-wave emission culminating a fraction of a second before the final fusion of the stars and a burst of highly energetic light (known as a <a href="https://en.wikipedia.org/wiki/Gamma-ray_burst">gamma-ray burst</a>) emitted by a jet of matter approaching the speed of light. Although these bursts have been observed regularly for several decades, it is only since 2015 that gravitational waves have been detectable on Earth thanks to the <a href="http://public.virgo-gw.eu">Virgo</a> and <a href="http://ligo.org/">LIGO</a> interferometers.</p>
<p>August 17 will remain a major date for the scientific community. Indeed, it marks the first simultaneous detection of the arrival of gravitational waves – whose origin in the sky was fairly well identified – and a gamma-ray burst, whose origin was also fairly well localized and coincided with the first one. Gamma-ray burst emissions are focused in a narrow cone, and the astronomers’ lucky break was that this one was emitted in the Earth’s direction.</p>
<p>In the following days, telescopes continuously analysed the light from this kilonova and found confirmation of the production of elements heavier than iron. They were also able to estimate the frequency of the phenomenon and the amount of material ejected. These estimates are consistent with the average abundance of the elements observed in our galaxy.</p>
<p>In a single observation, the hypothesis that prevailed until now – of a <em>r</em> process occurring exclusively during supernovae – is now seriously under question and it is now certain that the <em>r</em> process also takes place in kilonovae. The respective contribution of supernovae and kilonovae for the heavy elements’ nucleo-synthesis remains to be determined, and it will be done with the accumulation of datum related to the next observations. The August 17 observation alone has already allowed a great scientific advance for the global understanding of the origin of heavy elements, including gold.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/x_Akn8fUBeQ?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This NASA animation is an artist’s view and accelerated version of the first nine days of a kilonova (the merging of two neutron stars) similar to that observed on August 17, 2017 (GW170817). In the approach phase of the two stars, the gravitational waves emitted are coloured pale blue, then after the fusion a jet near the speed of light is emitted (in orange) generating itself a gamma burst (in magenta). The material ejected from the kilonova produces an initially ultraviolet light (violet), then white in the optics, and finally infra-red (red). The jet continues its expansion by emitting light in the X-ray range (blue)</span></figcaption>
</figure>
<h2>A new window on the Universe</h2>
<p>A new window to the universe has just been opened, like the day that Galileo focused the first telescope on the sky. The Virgo and LIGO <a href="https://en.wikipedia.org/wiki/Interferometry">interferometers</a> now make it possible to “hear” the most violent phenomena of the universe, and immense perspectives have opened up for astronomers, astrophysicists, particle physicists and nuclear physicists. This scientific achievement was only possible thanks to the fruitful collaboration between highly supportive nations, in particular the United States, Germany, France and Italy. As an example, there is only one laboratory in the world capable of reaching the required precision for the mirrors reflecting lasers, <a href="http://lma.in2p3.fr/Lmagb.htm">LMA in Lyon, France</a>. New interferometers are under development in Japan and Indian, and this list will surely soon become longer given huge discoveries expected for the future.</p><img src="https://counter.theconversation.com/content/88880/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jérôme Margueron is CNRS researcher and a member of the Société Française de Physique (SFP).</span></em></p>The precious metal is literally extra-terrestrial, produced in the heart of the stars. How and under what conditions? Scientists know more thanks to a double astrophysical observation.Jérôme Margueron, Chercheur en astrophysique nucléaire, University of WashingtonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/841232017-11-06T06:10:41Z2017-11-06T06:10:41ZHeard of the element erbium? It could pave the way to a quantum internet<figure><img src="https://images.theconversation.com/files/193366/original/file-20171106-1017-to7lbe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A laser beam (yellow) causes a path of red fluorescence in a rare earth crystal. </span> <span class="attribution"><span class="source">Stuart Hay, ANU</span>, <span class="license">Author provided</span></span></figcaption></figure><p>If you were to try reciting the periodic table, you might stumble before you got to the rare earth elements. </p>
<p>Comprising yttrium (element 39) and everything from lanthanum (element 57) to lutetium (element 71), the rare earths are unfamiliar to most of us. But they are vital for technologies that we use every day, from fluorescent lights to the internet.</p>
<p>Recently, <a href="https://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys4254.html">we have shown</a> that one rare earth element, erbium (element 68), can play a crucial part in the future quantum internet.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-periodic-table-from-its-classic-design-to-use-in-popular-culture-52822">The periodic table: from its classic design to use in popular culture</a>
</strong>
</em>
</p>
<hr>
<h2>What are rare earths, anyway?</h2>
<p>Even the name “rare earths” is misleading. In fact, rare earth elements are not particularly rare. Cerium, for example, is as common as copper. </p>
<p>The name “rare earths” came about because they are dispersed in ores and are difficult to extract, so only small amounts could be isolated. Today, though, we extract over <a href="https://foreignpolicy.com/2016/07/12/decoder-rare-earth-market-tech-defense-clean-energy-china-trade/">100,000 tonnes</a> of rare earth elements annually.</p>
<p>The applications of the rare earth elements are wide ranging. Metal alloys – that is, mixtures – containing rare earth ions such as neodymium make the strongest magnets. They’re used in everything from audio speakers to electric motors. The catalytic converters that reduce harmful emissions in car exhausts use cerium, and rechargeable nickel metal hydride batteries use lanthanum.</p>
<p>Crystals containing rare earth ions absorb and emit light at a variety of useful wavelengths in the ultraviolet, visible and infrared ranges of the spectrum. </p>
<p>This means that rare earth elements are common in lighting. Crystal powders - known as phosphors - containing europium, terbium, and cerium are used to create the red, green, and blue pixels that make up a full-colour plasma television display. They’re also mixed together to create the white light from compact fluorescent light bulbs.</p>
<h2>Erbium and the internet</h2>
<p>Erbium, meanwhile, plays a vital role in the internet’s optical fibre network. </p>
<p>Most global internet traffic travels as light in optical fibres. This allows fast transmission with very low loss at the right wavelength (around 1,500-1,600 nanometres; one nanometre is one billionth of a metre). </p>
<p>Even so, over long distances this loss - light leaking out of the fibre - is a major problem, and the light has to be periodically amplified. </p>
<p>Since erbium absorbs and emits light at 1,550 nanometres, exactly in the middle of the fibre telecom band, it can be used to amplify the light in a device called an Erbium-Doped Fibre Amplifier (EDFA). </p>
<p>The undersea optical fibres that form the backbone of the internet have EDFAs <a href="https://www.osa-opn.org/home/articles/volume_25/march_2014/features/sea_change_the_challenges_facing_submarine_optical/">every 80km or so</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/193369/original/file-20171106-1061-1mcd7s1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/193369/original/file-20171106-1061-1mcd7s1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/193369/original/file-20171106-1061-1mcd7s1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/193369/original/file-20171106-1061-1mcd7s1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/193369/original/file-20171106-1061-1mcd7s1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/193369/original/file-20171106-1061-1mcd7s1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/193369/original/file-20171106-1061-1mcd7s1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Erbium-doped optical fiber, illuminated with green light.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/w/index.php?curid=23322774">Ximeg /wikimedia commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>The quantum internet</h2>
<p>The internet allows current-day computers to talk to each other, but researchers are now developing quantum computers. Erbium could play an important role here too.</p>
<p>Quantum computers make use of one of the stranger aspects of quantum physics - quantum superposition, where particles can simultaneously exist in two different states - to encode information. To get these computers talking to each other, we need a new type of network that can maintain this quantum information. In other words, a quantum internet. </p>
<p>To make the quantum internet we need to build the quantum analogues of each element in the classical internet. The quantum analogue of the EDFAs used as amplifiers in our current undersea optical fibres is called a quantum repeater. In turn, this would require quantum memory, which is used to store and synchronise information traffic in the network.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/from-flatscreen-tvs-to-your-smartphone-the-element-boron-deserves-more-attention-82374">From flatscreen TVs to your smartphone: the element boron deserves more attention</a>
</strong>
</em>
</p>
<hr>
<p>Researchers around the world have been working on quantum memories for over a decade, but storing quantum information for even 1/1,000 of a second is challenging. We need storage times of at least 1/10 second for the quantum internet. </p>
<p>It has also been very hard to make memories that work for light in the fibre telecom band, the wavelength required for optical fibres.</p>
<p>The best approach to date has been to build the memory at a different wavelength, and to try to interface it with the optical fibre band by, for example, converting the wavelength of the light at the input and output of the memory - a challenge in itself.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/193378/original/file-20171106-1068-wz6ctz.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/193378/original/file-20171106-1068-wz6ctz.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=394&fit=crop&dpr=1 600w, https://images.theconversation.com/files/193378/original/file-20171106-1068-wz6ctz.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=394&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/193378/original/file-20171106-1068-wz6ctz.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=394&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/193378/original/file-20171106-1068-wz6ctz.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=496&fit=crop&dpr=1 754w, https://images.theconversation.com/files/193378/original/file-20171106-1068-wz6ctz.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=496&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/193378/original/file-20171106-1068-wz6ctz.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=496&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Crystals containing erbium, which gives them their pink colour.</span>
<span class="attribution"><span class="source">Milos Rancic, ANU</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Will erbium help?</h2>
<p>Since erbium interacts with light at exactly the right wavelength, it seems like the obvious choice for a quantum memory. However, erbium is poor at storing quantum information. </p>
<p>The problem is that erbium is sensitive to the tiny magnetic field fluctuations that occur in crystals, and this rapidly degrades any quantum information it holds. </p>
<p>Recently, <a href="https://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys4254.html">we found</a> that applying a large magnetic field can greatly improve the quantum storage time of certain erbium crystals. This field, which is similar to that inside a hospital MRI machine, quiets the magnetic field fluctuations. The erbium storage time can then improve by a factor of 10,000 to more than 1 second.</p>
<p>This is the first system compatible with the optical fibres required for a global quantum internet that has a storage time long enough for this network. The next steps are to build quantum repeaters with this system, and install them on a test network to measure their performance. </p>
<p>In the future, erbium materials may be as integral to the quantum internet as they already are to our current internet.</p><img src="https://counter.theconversation.com/content/84123/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rose Ahlefeldt receives funding from the Australian Research Council. </span></em></p>Rare earth elements aren’t actually that rare - but they certainly are useful. Erbium is used right now in the internet’s optical fibre network, and could one day be applied in quantum networks.Rose Ahlefeldt, Research Fellow, Laser Physics Centre, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/861042017-10-24T20:18:24Z2017-10-24T20:18:24ZCosmic alchemy: Colliding neutron stars show us how the universe creates gold<figure><img src="https://images.theconversation.com/files/191637/original/file-20171024-30571-frs0vu.jpg?ixlib=rb-1.1.0&rect=96%2C0%2C803%2C573&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Illustration of hot, dense, expanding cloud of debris stripped from the neutron stars just before they collided.</span> <span class="attribution"><a class="source" href="https://svs.gsfc.nasa.gov/12740">NASA's Goddard Space Flight Center/CI Lab</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>For thousands of years, humans have searched for a way to turn matter into gold. <a href="https://doi.org/10.1086/660139">Ancient alchemists</a> considered this precious metal to be the highest form of matter. As human knowledge advanced, the mystical aspects of alchemy gave way to the sciences we know today. And yet, with all our advances in science and technology, the origin story of gold remained unknown. Until now. </p>
<p>Finally, scientists know how the universe makes gold. Using our <a href="https://doi.org/10.3847/2041-8213/aa91c9">most advanced telescopes and detectors</a>, we’ve seen it created in the cosmic fire of the two colliding stars first detected by LIGO via the gravitational wave they emitted.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/191658/original/file-20171024-30605-ei0pxa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The electromagnetic radiation captured from GW170817 now confirms that elements heavier than iron are synthesized in the aftermath of neutron star collisions.</span>
<span class="attribution"><a class="source" href="https://www.caltech.edu/news/caltech-led-teams-strike-cosmic-gold-80074">Jennifer Johnson/SDSS</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Origins of our elements</h2>
<p>Scientists have been able to piece together where many of the elements of the periodic table come from. The Big Bang <a href="https://doi.org/10.1146/annurev.nucl.56.080805.140437">created hydrogen</a>, the lightest and most abundant element. As stars shine, they fuse hydrogen into heavier elements like carbon and oxygen, the elements of life. In their dying years, stars create the common metals – aluminum and iron – and blast them out into space in different types of <a href="https://doi.org/10.1146/annurev.astro.38.1.191">supernova</a> <a href="https://doi.org/10.1146/annurev-astro-082708-101737">explosions</a>.</p>
<p>For decades, scientists have theorized that these stellar explosions also explained the origin of the heaviest and most rare elements, like gold. But they were missing a piece of the story. It hinges on the object left behind by the death of a massive star: a neutron star. Neutron stars pack one-and-a-half times the mass of the sun into a ball only 10 miles across. A teaspoon of material from their surface would weigh 10 million tons.</p>
<p>Many stars in the universe are in binary systems – two stars bound by gravity and orbiting around each other (think Luke’s home planet’s suns in “Star Wars”). A pair of massive stars might eventually end their lives as a pair of neutron stars. The neutron stars orbit each other for hundreds of millions of years. But Einstein says that their dance cannot last forever. Eventually, they must collide.</p>
<h2>Massive collision, detected multiple ways</h2>
<p>On the morning of August 17, 2017, a ripple in space passed through our planet. It was detected by the LIGO and Virgo gravitational wave detectors. This cosmic disturbance came from a pair of city-sized neutron stars colliding at one third the speed of light. The <a href="https://doi.org/10.1103/PhysRevLett.119.161101">energy of this collision</a> surpassed any atom-smashing laboratory on Earth.</p>
<p>Hearing about the collision, astronomers around the world, <a href="http://kilonova.org/about.html">including</a> <a href="https://dabrown.expressions.syr.edu/">us</a>, jumped into action. Telescopes large and small scanned the patch of sky where the gravitational waves came from. Twelve hours later, three telescopes caught sight of a brand new star – called a kilonova – in a galaxy called NGC 4993, about 130 million light years from Earth.</p>
<p>Astronomers had captured the light from the cosmic fire of the colliding neutron stars. It was time to point the world’s biggest and best telescopes toward the new star to see the visible and infrared light from the collision’s aftermath. In Chile, the Gemini telescope swerved its large 26-foot mirror to the kilonova. NASA steered the Hubble to the same location.</p>
<figure>
<img src="http://kilonova.org/img/DECam_fading_kn_final.gif">
<figcaption><span class="caption">Movie of the visible light from the kilonova fading away in the galaxy NGC 4993, 130 million light years away from Earth.</span></figcaption>
</figure>
<p>Just like the embers of an intense campfire grow cold and dim, the afterglow of this cosmic fire quickly faded away. Within days the visible light faded away, leaving behind a warm infrared glow, which eventually disappeared as well. </p>
<h2>Observing the universe forging gold</h2>
<p>But in this fading light was encoded the answer to the age-old question of how gold is made.</p>
<p>Shine sunlight through a prism and you will see our sun’s spectrum – the colors of the rainbow spread from short wavelength blue light to long wavelength red light. This spectrum contains the fingerprints of the elements bound up and forged in the sun. Each element is marked by a unique fingerprint of lines in the spectrum, reflecting the different atomic structure.</p>
<p>The spectrum of the kilonova contained the fingerprints of the heaviest elements in the universe. Its light carried the telltale signature of the neutron-star material decaying into platinum, gold and other so-called <a href="https://en.wikipedia.org/wiki/R-process">“r-process” elements</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/191689/original/file-20171024-30613-1iljobe.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Visible and infrared spectrum of the kilonova. The broad peaks and valleys in the spectrum are the fingerprints of heavy element creation.</span>
<span class="attribution"><span class="source">Matt Nicholl</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>For the first time, humans had seen alchemy in action, the universe turning matter into gold. And not just a small amount: This one collision created at least 10 Earths’ worth of gold. You might be wearing some gold or platinum jewelry right now. Take a look at it. That metal was created in the atomic fire of a neutron star collision in our own galaxy billions of years ago – a collision just like the one seen on August 17.</p>
<p>And what of the gold produced in this collision? It will be blown out into the cosmos and mixed with dust and gas from its host galaxy. Perhaps one day it will form part of a new planet whose inhabitants will embark on a millennia-long quest to understand its origin.</p><img src="https://counter.theconversation.com/content/86104/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Duncan Brown receives funding from the National Science Foundation and the Research Corporation for Science Advancement.</span></em></p><p class="fine-print"><em><span>Edo Berger receives funding from the National Science Foundation and NASA. </span></em></p>Until the recent observation of merging neutron stars, how the heaviest elements come to be was a mystery. But their fingerprints are all over this cosmic collision.Duncan Brown, Professor of Physics, Syracuse UniversityEdo Berger, Professor of Astronomy, Harvard UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/823742017-08-23T19:25:29Z2017-08-23T19:25:29ZFrom flatscreen TVs to your smartphone: the element boron deserves more attention<figure><img src="https://images.theconversation.com/files/182385/original/file-20170817-13456-yxzar.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Boron is often ignored, but it's got a lot of important qualities.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/david44149/14002811915/in/photolist-6nyvxh-awXnMC-duL3Zq-c6E7ef-c6E825-c6E7nC-8sZN1w-2DLgBv-bx8ddc-bmMReq-c6E78w-b7iMzt-nko58D-hucmVJ-99RxeL-8zABdh-8zxskk-7o8Kcr-8zxsoZ-AFyjqN-4qkZcg-99Rxfo-8zAB3Q-x7Hxws">David Ellis/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>Each time you watch sport on a flatscreen television, or send a message by touching your smartphone screen, give thanks to an unsung hero of the periodic table: boron.</p>
<p>Boron, often wrongly labelled a “boring” element, plays a versatile role in our lives. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-periodic-table-from-its-classic-design-to-use-in-popular-culture-52822">The periodic table: from its classic design to use in popular culture</a>
</strong>
</em>
</p>
<hr>
<p>It’s the key ingredient in borosilicate glass, which is known for its exceptional resistance to thermal change and chemicals, and its ability to withstand impact. This means glass cookware can go into a hot oven straight from the freezer, and that lab equipment such as beakers and test tubes can withstand corrosion.</p>
<p>Neodymium magnets, in which boron plays a role in the formation of the crystal structure and retaining magnetisation, are among the strongest permanent magnets commercially available. Boron is also used to prepare detergents, buffer solution, insecticides, insulation and semiconductors.</p>
<p>Australia’s soils can be <a href="http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0005/158864/boron-deficiency-pastures-field-crops.pdf">deficient in boron</a>, and boron-containing fertiliser is used to help with root growth and flowering.</p>
<p>Although I research boron chemistry for energy conversion and storage, the element has a rich history with many practical applications.</p>
<h2>What makes boron so special?</h2>
<p>Due to its reactivity, boron naturally exists only in combination with other elements, forming boric acid and inorganic salts known as borates. </p>
<p>One key reason why boron is so versatile is its electron-deficient nature, which means it’s very inclined to accept electrons from other elements and easily forms many interesting compounds with both metals and non-metals.</p>
<p>For example, metal borides, compounds formed between metal (M) and boron (B), such as rhenium diboride, have high hardness due to extensive B-B and M-B bonds. There’s also boron carbide, which is an extremely hard and light ceramic used in bullet proof vests and tank armour.</p>
<p>Boron-10 (10B), <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5296588/">a stable isotope</a> that can be isolated by extensive distillation of volatile boron compounds, has led to Boron Neutron Capture Therapy (BNCT) <a href="https://www.sciencedaily.com/releases/2011/03/110304091901.htm">that treats</a> locally invasive malignant tumours, such as recurrent head and neck cancer.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/182734/original/file-20170821-27160-7mpjkd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/182734/original/file-20170821-27160-7mpjkd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=592&fit=crop&dpr=1 600w, https://images.theconversation.com/files/182734/original/file-20170821-27160-7mpjkd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=592&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/182734/original/file-20170821-27160-7mpjkd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=592&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/182734/original/file-20170821-27160-7mpjkd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=744&fit=crop&dpr=1 754w, https://images.theconversation.com/files/182734/original/file-20170821-27160-7mpjkd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=744&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/182734/original/file-20170821-27160-7mpjkd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=744&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A Boron Neutron Capture Therapy ADAM Injector with (L to R) Enrique Henestroza, Joe Kwan and Lou Reginato that constructed a proton accelerator that will be a key element in new brain cancer treatment.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/berkeleylab/3525773210/in/photolist-6nyvxh-awXnMC-duL3Zq-c6E7ef-c6E825-c6E7nC-8sZN1w-2DLgBv-hucmVJ-bx8ddc-bmMReq-c6E78w-99RxeL-AFyjqN-b7iMzt-nko58D-8zABdh-8zxskk-7o8Kcr-8zxsoZ-4qkZcg-99Rxfo-8zAB3Q-x7Hxws">Berkeley Lab</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Notably, the Nobel Prize for Chemistry has been awarded <a href="https://www.nobelprize.org/nobel_prizes/chemistry/laureates/1976/press.html">at least</a> <a href="https://www.nobelprize.org/nobel_prizes/chemistry/laureates/1979/">three times</a> to scientists working in the field of boron chemistry. </p>
<p>One recent contribution is the “Suzuki Coupling” reaction in 2010, <a href="http://www.nobelprize.org/nobel_prizes/chemistry/laureates/2010/">which revolutionised</a> chemical synthesis and supports product developments such as Organic Light Emitting Display (OLED), which can be used for thin, colourful TVs.</p>
<h2>Boron versus carbon</h2>
<p>Boron and carbon are neighbouring elements in the periodic table and are similar in many ways. Carbon has arguably enjoyed greater publicity, however. Most recently, a lot of attention has been paid <a href="https://theconversation.com/harder-than-diamond-stronger-than-steel-super-conductor-graphenes-unreal-5123">to graphene</a> – one atomic layer of carbon atoms – which has many potential high-tech uses.</p>
<p>Similar to hydrocarbons, boron forms a series of neutral boranes that were once studied as rocket fuel because they produce an enormous amount of energy when reacting with oxygen. But they often proved toxic and too difficult to control.</p>
<p>Elemental boron exists <a href="https://books.google.com.au/books?id=FA7VAwAAQBAJ&pg=PT268&lpg=PT268&dq=boron+16+allotropes&source=bl&ots=XBVva5OMx_&sig=Z_tOoLzt1vkwIvye7wwqQ3ByhHE&hl=en&sa=X&ved=0ahUKEwiz_YG_xOzVAhVJNJQKHbQ7CScQ6AEIWzAJ#v=onepage&q=boron%2016%20allotropes&f=false">in 16 known</a> “allotropes” – different forms of the same element. Carbon has two common ones: diamond and graphite.</p>
<p>The difficulty in controlling the formation of desired boron allotropes slows down research. In contrast, carbon materials can be easily prepared and studied. </p>
<h2>A pivotal role in energy conversion and storage</h2>
<p>It is exciting to see scientists around the globe beavering away in labs, finding new ways to use this plucky little element.</p>
<p>Here are some of the big questions they’re tackling:</p>
<p><strong>1. Boron as a source of energy</strong></p>
<p>Some researchers are examining whether we can get energy from boron using <a href="https://www.nasa.gov/directorates/spacetech/niac/tarditi_aneutronic_fusion.html">aneutronic fusion</a> – a form of fusion power in which negligible amounts of neutrons are released.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/182735/original/file-20170821-27189-1uni6u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/182735/original/file-20170821-27189-1uni6u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/182735/original/file-20170821-27189-1uni6u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/182735/original/file-20170821-27189-1uni6u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/182735/original/file-20170821-27189-1uni6u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/182735/original/file-20170821-27189-1uni6u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/182735/original/file-20170821-27189-1uni6u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Boron.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/jcburns/20423064426/in/photolist-6nyvxh-awXnMC-duL3Zq-c6E7ef-c6E825-c6E7nC-8sZN1w-2DLgBv-hucmVJ-bx8ddc-bmMReq-c6E78w-99RxeL-AFyjqN-b7iMzt-nko58D-8zABdh-8zxskk-7o8Kcr-8zxsoZ-4qkZcg-99Rxfo-8zAB3Q-x7Hxws">J.C. Burns</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p><strong>2. Boron as an energy carrier</strong></p>
<p>Compounds containing boron, nitrogen and hydrogen can effectively store and transfer hydrogen. This is important because hydrogen is an ideal candidate <a href="http://pubs.rsc.org/en/content/articlelanding/2012/ee/c2ee23039a/unauth#!divRelatedContent&articles">to store energy</a> produced by wind farm and solar plants. </p>
<p>Sodium difluoro (oxalato) borate, on the other hand, can outperform some commercial compounds as an electrolyte salt for emerging sodium-ion batteries, which could be <a href="http://www.boronmolecular.com/Na-ionBatteryElectrolytes">a great candidate</a> for large-scale energy storage.</p>
<p><strong>3. Boron for heat conservation</strong></p>
<p>Some solar water heating and solar power generation plants are using borosilicate collector tubes to harness reflected radiation from mirrors, so the steam turbines can be driven in a more efficient way. </p>
<p>We have also seen more stringent building standards with respect to heat conservation, promoting the use of borates for fiberglass insulation.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-search-for-new-elements-on-the-periodic-table-started-with-a-blast-52862">The search for new elements on the periodic table started with a blast</a>
</strong>
</em>
</p>
<hr>
<p>Impressed? </p>
<p>Should boron get more of the spotlight?</p>
<p>I’m sure we will see boron continue to be a star in our tech-driven society. From fertiliser to OLED screens, it’s poised to have a big impact.</p><img src="https://counter.theconversation.com/content/82374/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zhenguo Huang receives funding from Australian Research Council and U.S. Borax. </span></em></p>Boron is the hidden ingredient in a lot of our technology. Get to know this plucky little element.Zhenguo Huang, Senior Research Fellow in Energy, University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/528222017-04-02T19:32:41Z2017-04-02T19:32:41ZThe periodic table: from its classic design to use in popular culture<figure><img src="https://images.theconversation.com/files/113029/original/image-20160226-26723-15gnsbs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The periodic table of the elements on a T-shirt.</span> <span class="attribution"><a class="source" href="http://mirror-au-nsw1.gallery.hd.org/_c/textures/_more2005/_more05/periodic-table-of-the-elements-printed-on-ancient-cotton-T-shirt-rotated-lowres-DHD.jpg.html">Damon Hart Davis</a></span></figcaption></figure><p>The periodic table is one of those classic images that you find in many science labs and classrooms. It’s an image almost everyone has seen at some time in their life.</p>
<p>You can also find the periodic table on <a href="https://www.questacon.edu.au/qshop/Questacon-Periodic-Table-T-shirt/">t-shirts</a>, <a href="http://shop.australiangeographic.com.au/mug-periodic-table.html">mugs</a>, <a href="https://www.getdigital.eu/Periodic-Table-Beach-Towel.html">beach towels</a>, <a href="https://www.amazon.com/Periodic-Chemical-Elements-Novelty-Pillowcase/dp/B00QFJXNVS">pillowcases</a> and <a href="http://www.cafepress.com.au/+periodic-table-chemical-elements+duvet-covers">duvet covers</a>, and <a href="http://www.cafepress.com.au/+periodic-table+gifts">plenty of other items</a>. It even inspired a <a href="https://www.theguardian.com/science/2009/oct/09/primo-levi-periodic-table">collection of short stories</a>. </p>
<p>Who can forget the periodic table put to music by the American <a href="http://www.allmusic.com/artist/tom-lehrer-mn0000611877/biography">Tom Lehrer</a>, a Harvard mathematics professor who was also a singer/songwriter and satirist. His song, The Elements, includes all the elements that were known at the time of writing in 1959.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/zGM-wSKFBpo?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>Since then, several new elements have been added to the periodic table, including the <a href="https://theconversation.com/four-new-elements-named-heres-how-the-periodic-table-evolved-60276">four</a> that were <a href="https://iupac.org/iupac-announces-the-names-of-the-elements-113-115-117-and-118/">formally approved last year</a> by the International Union of Pure and Applied Chemistry (IUPAC).</p>
<p>But what exactly does the periodic table show?</p>
<p>In brief, it is an attempt to organise the collection of the elements – all of the known pure compounds made from a single type of atom.</p>
<p>There are two ways to look at how the periodic table is constructed, based on either the observed properties of the elements contained within it, or on the subatomic construction of the atoms that form each element.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/155128/original/image-20170201-12656-1hd5emj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The basic modern periodic table.</span>
<span class="attribution"><span class="source">Shutterstock/duntaro</span></span>
</figcaption>
</figure>
<h2>The elements</h2>
<p>When scientists began collecting elements in the 1700s and 1800s, slowly identifying new ones over decades of research, they began to notice patterns and similarities in their physical properties. Some were gases, some were shiny metals, some reacted violently with water, and so on. </p>
<p>At the time when elements were first being discovered, the structure of atoms was not known. Scientists began to look at ways to arrange them systematically so that similar properties could be grouped together, just as someone collecting seashells might try to organise them by shape or colour.</p>
<p>The task was made more difficult because not all of the elements were known. This left gaps, which made deciphering patterns a bit like trying to assemble a jigsaw puzzle with missing pieces.</p>
<p>Different scientists came up with different types of tables. The first version of the current table is generally attributed to Russian chemistry professor <a href="http://www.britannica.com/biography/Dmitry-Ivanovich-Mendeleyev">Dmitri Mendeleev</a> in 1869, with an updated version in 1871.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=350&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=350&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=350&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=439&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=439&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116741/original/image-20160330-28455-1ror2vj.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=439&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mendeleev’s periodic table is first published outside Russia in Zeitschrift für Chemie (1869, pages 405-6).</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Mendeleev%27s_periodic_table_(1869).svg">Wikimedia/Dimitri Mendeleev</a></span>
</figcaption>
</figure>
<p>Importantly, Mendeleev left gaps in the table where he thought missing elements should be placed. Over time, these gaps were filled in and the final version as we know it today emerged.</p>
<h2>The atoms</h2>
<p>To really understand the final structure of the periodic table, we need to understand a bit about atoms and how they are constructed. Atoms have a central core (the nucleus) made up of smaller particles called protons and neutrons.</p>
<p>It is the number of protons that gives an element its atomic number – the number generally found in the top left corner of each box in the periodic table. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=195&fit=crop&dpr=1 600w, https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=195&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=195&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=245&fit=crop&dpr=1 754w, https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=245&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/155129/original/image-20170201-12685-525wu2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=245&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The properties of hydrogen as marked on the periodic table.</span>
<span class="attribution"><span class="source">Shutterstock/duntaro</span></span>
</figcaption>
</figure>
<p>The periodic table is arranged in order of increasing atomic number (left to right, top to bottom). It ranges from element 1 (hydrogen <a href="http://www.rsc.org/periodic-table/element/1/hydrogen">H</a>) in the top left, to the newly approved element 118 (oganesson <a href="http://www.rsc.org/periodic-table/element/118/oganesson">Og</a>) in the bottom right.</p>
<p>The number of neutrons in the nucleus can vary. This gives rise to different isotopes for every element. </p>
<p>For example, you may have heard of <a href="http://science.howstuffworks.com/environmental/earth/geology/carbon-14.htm">carbon-14 dating</a> to determine the age of objects. This isotope is a radioactive version of normal carbon <a href="http://www.rsc.org/periodic-table/element/6/carbon">C</a> (or carbon-12) that has two extra neutrons.</p>
<p>But why is there a separate box of elements below the main table, and why is the main table an odd shape, with a bite taken out of the top? That comes down to how the other component of the atom – the electrons – are arranged.</p>
<h2>The electrons</h2>
<p>We tend to think of atoms as built a bit like onions, with seven layers of electrons called “shells”, labelled K, L, M, N, O, P, and Q, surrounding the core nucleus.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=318&fit=crop&dpr=1 600w, https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=318&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=318&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=399&fit=crop&dpr=1 754w, https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=399&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/126483/original/image-20160614-29205-4s6tgg.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=399&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Think of the atom with a central nucleus that contains all the protons and neutrons, surrounded by a series of shells that contain the electrons.</span>
<span class="attribution"><span class="source">The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Each row in the periodic table sort of corresponds to filling up one of these shells with electrons. Each shell has subshells, and the order in which the shells/subshells get filled is based on the energy required, although it’s a complicated process. We’ll come back to these later.</p>
<p>In simple terms, the first element in each row starts a new shell containing one electron, while the last element in each row has two (or one for the the first row) of the subshells in the outer shell fully occupied. These differences in electrons also account for some of the similarities in properties between elements. </p>
<p>With the one or two subshells in the outer layer full of electrons, the last elements of each row are quite unreactive, as there are no holes or gaps in the outer shell to interact with other atoms.</p>
<p>This is why elements in the last column, such as helium <a href="http://www.rsc.org/periodic-table/element/2/helium">He</a>, neon (<a href="http://www.rsc.org/periodic-table/element/10/neon">Ne</a>), argon (<a href="http://www.rsc.org/periodic-table/element/18/argon">Ar</a>) and so on, are called the <a href="http://www.britannica.com/science/noble-gas">noble gases</a> (or inert gases). They are all gases and they are “noble” because they rarely associate with other elements.</p>
<p>In contrast, the elements of the first column, with the exception of hydrogen (just like English grammar, there’s always an exception!), are called alkali metals. The first-column elements are metal-like in character, but with only one electron in the outer shell, they are very reactive as this lone electron is very easy to engage in chemical bonding. When added to water, they quickly react to form an alkaline (basic) solution.</p>
<p>Each shell can accommodate an increasing number of electrons. The first shell (K) only fits two, so the first row of the periodic table has only two elements: hydrogen (<a href="http://www.rsc.org/periodic-table/element/1/hydrogen">H</a>) with one electron, and helium (<a href="http://www.rsc.org/periodic-table/element/2/helium">He</a>) with two.</p>
<p>The second shell (L) fits eight electrons. Thus the second row of the periodic table contains eight elements, with a gap left between hydrogen and helium to accommodate the extra six. </p>
<p>The third shell (M) fits 18 electrons, but the third row still only has eight elements. This is because the extra ten electrons don’t get added to this layer until after the first two electrons are added to the fourth shell (N) (we’ll get to why, later).</p>
<p>So the gap is expanded in the fourth row to accommodate the additional ten elements, leading to the “bite” out of the top of the table. The extra ten compounds in the middle section are called the <a href="http://www.britannica.com/science/transition-element">transition metals</a>.</p>
<p>The fourth shell holds 32 electrons, but again the extra electrons are not added to this shell until some have also been added to the fifth (O) and sixth (P) shells, meaning that both the fourth and fifth rows hold 18 elements. </p>
<p>For the next two rows (sixth and seventh), rather than further expanding the table sideways to include these extra 14 elements, which would make it too wide to easily read, they have been inserted as a block of two rows, called the <a href="http://www.britannica.com/science/lanthanoid">lanthanoids</a> (elements 57 to 71) and <a href="http://www.britannica.com/science/actinoid-element">actinoids</a> (elements 89 to 103), below the main table.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=359&fit=crop&dpr=1 600w, https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=359&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=359&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=451&fit=crop&dpr=1 754w, https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=451&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/154931/original/image-20170131-13243-135rr77.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=451&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The periodic table would look very different if the lanthanoids and actinoids were inserted within the table.</span>
<span class="attribution"><span class="source">The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>You can see where they would fit in if the periodic table was widened, if you look at the bottom two squares in the third column of the table above.</p>
<h2>Across the columns</h2>
<p>There is another complicating factor leading to the final shape of the table. As mentioned earlier, as the electrons are added to each layer they go into different subshells (or orbitals), which describes locations around the nucleus where they are most likely to be found. These are known by the letters s, p, d and f.</p>
<p>The letters used for the orbitals are actually derived from descriptions of the emission or absorption of light due to electrons moving between the orbitals: <strong>s</strong>harp, <strong>p</strong>rincipal, <strong>d</strong>iffuse and <strong>f</strong>undamental.</p>
<p>Each shell has its own configuration of subshells named from 1s through to 7p, which gives the total number of electrons in each shell as we progress through the periodic table. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=489&fit=crop&dpr=1 600w, https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=489&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=489&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=615&fit=crop&dpr=1 754w, https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=615&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/163552/original/image-20170402-27256-u5wjt7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=615&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>As mentioned earlier the order in which the subshells fill with electrons is not so straightforward. You can see the order in which they fill from the image below, just follow the order as you would read down from left to right.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=353&fit=crop&dpr=1 600w, https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=353&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=353&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=444&fit=crop&dpr=1 754w, https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=444&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/163745/original/image-20170403-21969-flm80p.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=444&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>There is an <a href="http://www.ptable.com/#Orbital">interactive periodic table</a> that also illustrates the filling sequence well if you click through the atoms.</p>
<p>Elements within a column generally have similar properties, but in some places elements side by side can also be similar. For example, in the transition metals the cluster of precious metals around copper (<a href="http://www.rsc.org/periodic-table/element/29/copper">Cu</a>), silver (<a href="http://www.rsc.org/periodic-table/element/47/silver">Ag</a>), gold (<a href="http://www.rsc.org/periodic-table/element/79/gold">Au</a>), palladium (<a href="http://www.rsc.org/periodic-table/element/46/palladium">Pd</a>) and platinum (<a href="http://www.rsc.org/periodic-table/element/78/platinum">Pt</a>) are quite alike.</p>
<p>Most of the existing elements with high atomic numbers, including the <a href="https://theconversation.com/the-race-to-find-even-more-new-elements-to-add-to-the-periodic-table-52747">four superheavy elements added last year</a>, are very unstable and have never been detected in, or isolated from, nature. </p>
<p>Instead, they are created and analysed in minute quantities under highly artificial conditions. Theoretically, there could be further elements beyond the 118 now known (there are additional g, h and i suborbitals), but we don’t know yet if any of these would be stable enough to be isolated.</p>
<h2>A classic design</h2>
<p>The periodic table has seen many colourful and informative versions created over the years.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/150468/original/image-20161216-26116-qgzp6m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Periodic table decorates a taxi in the UK.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/gashwin/6959094671/">Flickr/Fr Gaurav Shroff</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>One of my favourites is an <a href="http://www.raci.org.au/periodic-table-on-show">artistic version</a> with original artworks for each element commissioned by the Royal Australian Chemical Institute to celebrate the International Year of Chemistry in 2011.</p>
<p>Another favourite is an <a href="http://www.periodictable.com/index.html">interactive version</a> with pictures of the elements. The creators of this site have also published a coffee table book called <a href="http://www.periodictable.com/Posters/index.theelements.html">The Elements</a> and an <a href="http://www.periodictable.com/Posters/index.theelementsipad.html">Apple app</a> with videos of each element.</p>
<p><a href="http://www.rsc.org/periodic-table">Interactive versions</a> have also been created by the Royal Society of Chemistry (and can also be downloaded as an app) and <a href="http://www.chemeddl.org/resources/ptl/index.php">ChemEd DL</a> among others.</p>
<p>The classic design of the periodic table can be used to play a version of the <a href="http://teachbesideme.com/periodic-table-battleship/">Battleship</a> game.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/118104/original/image-20160411-6250-1lbc5v4.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Playing battleships with the periodic table at the first World Science Festival Brisbane in 2016.</span>
<span class="attribution"><span class="source">The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>There are also many fun versions created to help organise a multitude of objects, including <a href="http://grafikdzine.deviantart.com/art/Periodic-Food-Table-114678046">food</a>, <a href="http://beergeno.me/wp-content/uploads/2010/10/Per_iodic_Table_Beer_Styles.png">beer</a>, <a href="http://www.fastcocreate.com/3039715/ge-drops-some-social-science-with-the-periodic-table-of-emojis">emojis</a>, <a href="http://ictevangelist.com/wp-content/uploads/2014/07/PTAPPS-ICTEvangelist.png">iPad apps</a> and <a href="http://grosdino.deviantart.com/art/Periodic-Table-of-the-Birds-401058406">birds</a>.</p>
<p>As for Tom Lehrer’s The Elements, the song has yet to be updated to include all the elements known today but it has been covered by other people over the years. </p>
<p>Actor Daniel Radcliffe, of Harry Potter fame, performed a version during a guest appearance on the BBC’s Graham Norton Show.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/rSAaiYKF0cs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>There are <a href="https://www.youtube.com/watch?v=VgVQKCcfwnU">other musical versions</a> of the elements but they too have yet to be updated to include all entries of the periodic table.</p>
<p>In summary, the periodic table is the chemist’s taxonomy of all elements. Its triumph is that it is still highly relevant to scientists, while also becoming embedded in popular culture.</p><img src="https://counter.theconversation.com/content/52822/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Blaskovich receives funding from the Australian National Health and Medical Research Council (NHMRC) and the Wellcome Trust. He is a member of the Royal Australian Chemical Institute and the American Chemical Society.</span></em></p>The periodic table is one of the classic images of science that is found in labs as well as on t-shirts, mugs, even set to music. But what exactly is the periodic table?Mark Blaskovich, Senior Research Officer, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/608412016-06-09T17:23:34Z2016-06-09T17:23:34ZIt’s elemental: how to become a periodic table pub quiz champion<figure><img src="https://images.theconversation.com/files/125971/original/image-20160609-7049-130dk32.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">What's in a name?</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/dl2_lim.mhtml?src=gb4wr4jug4vndzUhvhIPbg-1-9&clicksrc=download_btn_inline&id=369111563&size=medium_jpg&submit_jpg=">Shutterstock</a></span></figcaption></figure><p>With the naming of <a href="https://theconversation.com/four-new-elements-named-heres-how-the-periodic-table-evolved-60276">four new chemical elements</a>, it’s worth reflecting on their <a href="http://www.nndc.bnl.gov/content/elements.html">long and interesting history</a> – and you can become a pub quiz champion on the topic in the process. Indeed, while the periodic table may sound like a rather dry topic, it’s actually a subject packed full of the weird and wonderful.</p>
<p>The concept of discrete atoms was proposed by Robert Boyle in 1661, but in the first chemistry textbook, Traité élémentaire de chimie, published in that portentous, revolutionary year of 1789, <a href="http://gallica.bnf.fr/ark:/12148/btv1b8615746s/f15.image.r=.langEN">Antoine-Laurent de Lavoisier</a> listed a number of the chemical elements, including 27 known today. They included hydrogen, nitrogen, oxygen, phosphorus, sulfur, iron, zinc, mercury and gold.</p>
<p>Not that it did him any good. Lavoisier was guillotined during the Reign of Terror in 1794, the judge allegedly commenting <a href="https://www.acs.org/content/dam/acsorg/education/whatischemistry/landmarks/lavoisier/antoine-laurent-lavoisier-commemorative-booklet.pdf">“La République n'a pas besoin de savants ni de chimistes”</a> (“The Republic does not need scientists or chemists”).</p>
<p>It was Lavoisier’s contemporary, <a href="http://www.britannica.com/biography/Nicolas-Louis-Vauquelin">Louis Nicolas Vauquelin</a> who not only discovered the element <a href="http://www.rsc.org/periodic-table/element/4/beryllium">beryllium</a> in 1798 but also in 1803 synthesised the oxide of another new element. Finding it to be volatile, he gave it the baffling name “ptene”, derived from the Greek word for winged. Fortunately for posterity, this element is now known as <a href="http://www.rsc.org/periodic-table/element/76/osmium">osmium</a> (from the ozone-like smell of the oxide) and so far, no unpronounceable name has been adopted for any element.</p>
<h2>118: the magic number?</h2>
<p>Since the start of the 19th century, the number of known elements has steadily risen, reaching its present total of 118. <a href="http://www.world-nuclear.org/information-library/nuclear-fuel-cycle/introduction/what-is-uranium-how-does-it-work.aspx">Uranium</a> (number 92) is the heaviest element present in the Earth in an appreciable amount and all successive elements have been made in scientific laboratories. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/125972/original/image-20160609-7059-hru8f8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/125972/original/image-20160609-7059-hru8f8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125972/original/image-20160609-7059-hru8f8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125972/original/image-20160609-7059-hru8f8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125972/original/image-20160609-7059-hru8f8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125972/original/image-20160609-7059-hru8f8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125972/original/image-20160609-7059-hru8f8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Nagasaki: the dark side or uranium.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/dl2_lim.mhtml?src=C6hNLn0UwzAfUtvW1n9kEA-1-6&clicksrc=download_btn_inline&id=251930701&size=medium_jpg&submit_jpg=">Shutterstock</a></span>
</figcaption>
</figure>
<p>The International Union of Pure and Applied Chemistry (IUPAC) has proposed names for <a href="http://iupac.org/cms/wp-content/uploads/2016/06/Press-Release_Naming-Four-New-Elements_8June2016.pdf">four recently synthesised chemical elements</a>, which complete the Periodic Table up to and including element 118.</p>
<p>Until now, this quartet have been known by their atomic numbers of 113, 115, 117 and 118 – or the temporary names of ununtrium (symbol Uut), ununpentium (Uup), ununseptium (Uus), and ununoctium (Uuo) respectively. The proposed names now are respectively nihonium (symbol Nh), moscovium (Mc), tennessine (Ts), and oganesson (Og).</p>
<p>Most elements have names ending in “–ium”. All but one of those are metals or metalloids; the one exception being <a href="http://www.rsc.org/periodic-table/element/2/helium">helium</a>, first discovered in the sun’s spectrum in 1868 and given its name from the Greek word for the sun – ἥλιος (helios) – before helium was identified on Earth (1895) and the character of the element could be known.</p>
<p>Two of these new elements are given names ending in –ium, though no one yet knows if they are metallic or not; the names of the other two are given endings appropriate to their positions in the Periodic Table. Tennessine is assigned to Group 17 (VIIB), together with the halogens fluorine, chlorine, bromine, iodine and astatine. Oganesson is in Group 18 (0), together with helium, neon, argon, krypton, xenon and radon.</p>
<p>The right to give a name to a newly discovered element is prestigious and has traditionally been seen to be in the hands of the discoverers. Four countries have contributed to the discoveries of new elements during the past half century. The work of the <a href="https://www.gsi.de/en/start/news.htm">German GSI Helmholtz Centre for Heavy Ion Research</a> at Darmstadt in discovering elements 107-112 – bohrium, meitnerium, hassium, darmstadtium, roentgenium and copernicum (as well as important confirmatory work on other elements) – is commemorated in their names. </p>
<p>As the leading German researcher Sigurd Hofmann <a href="http://www.popsci.com/scitech/article/2009-06/whats-it-name-element-periodic-table">commented</a>: </p>
<blockquote>
<p>We are being very democratic about naming. We are very careful, because these names last forever. We want the name to make sense now and forever – a famous scientist, famous lab, maybe a Greek philosopher.</p>
</blockquote>
<p>So don’t expect Boaty McBoatfacium just yet.</p>
<h2>What’s in a name?</h2>
<p>Of the four newest elements, two names are linked to Russia, one to Japan and one to the US, reflecting the international nature of the synthesis of these new man-made elements. But things have not always been like that.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/125973/original/image-20160609-7049-y0fkh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/125973/original/image-20160609-7049-y0fkh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125973/original/image-20160609-7049-y0fkh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125973/original/image-20160609-7049-y0fkh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125973/original/image-20160609-7049-y0fkh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125973/original/image-20160609-7049-y0fkh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125973/original/image-20160609-7049-y0fkh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">And I shall name it…</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&search_tracking_id=xnKAk0SAZ3_s0PwAjcsWUw&searchterm=chemical%20elementts&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=321825182">Shutterstock</a></span>
</figcaption>
</figure>
<p>Originally, this kind of nuclear synthesis was only carried out in the US at the <a href="http://www.berkeley.edu">University of California, Berkeley</a>, between 1940 and 1955, so they gave names to elements 93 (neptunium) to 101 (mendelevium). But the discovery of the next few elements was dominated by controversy, as both American and Soviet researchers were active, both schools claiming priority in discovery. The <a href="http://cenblog.org/newscripts/2011/08/whats-in-a-name-for-chemists-their-fields-soul/">Transfermium Wars</a> had begun, and it was not until the beginning of a new millennium that these names were sorted out by an <a href="http://www.degruyter.com/dg/viewarticle.fullcontentlink:pdfeventlink/$002fj$002fpac.1997.69.issue-12$002fpac199769122471$002fpac199769122471.pdf/pac199769122471.pdf?t:ac=j$002fpac.1997.69.issue-12$002fpac199769122471$002fpac199769122471.xml">international committee</a>.</p>
<p>Happily, international teams now work together to discover new chemical elements. Discoverers have often named a new element after their country, as with polonium (by Marie Curie) and americium, for example. Nihonium isn’t the first time that an element has taken its name from Japan. In 1909, the Japanese chemist Masataka Ogawa thought he had discovered element 43, and suggested that it be called <a href="http://pubs.acs.org/doi/abs/10.1021/ja01942a006">nipponium</a>.</p>
<p>But he hadn’t, so it wasn’t; we now know element 43 as technetium and it was not discovered until 1937. But it looks as if Ogawa had discovered a new element, rhenium, which was not recognised by others <a href="http://www.sciencedirect.com/science/article/pii/S0584854704001065">until 1925</a>.</p>
<h2>The whirligig of time</h2>
<p>Indeed, over the past centuries, many claims have been made in error for the discovery of elements; in most cases these have been <a href="http://www.rsc.org/chemistryworld/2015/02/lost-elements-periodic-table-shadow-side">innocent mistakes</a>, but a 1999 claim for the synthesis of elements 116 and 118 is now recognised to have involved fraud on the part of one of the <a href="http://physicsworld.com/cws/article/news/2001/aug/02/element-118-disappears-two-years-after-it-was-discovered">scientists involved</a>.</p>
<p>Not the least achievement of those who name compounds has been to set right historical injustices. <a href="http://www.atomicarchive.com/Bios/Meitner.shtml">Lise Meitner</a> was along with her colleague Otto Hahn a co-discoverer of <a href="http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa_pre_2011/radiation/nuclearfissionrev1.shtml">nuclear fission</a>, but did not share the award of the 1944 Nobel Prize in Chemistry for this; it went solely to Hahn. </p>
<p>In 1994, however, IUPAC recommended the adoption of the names hahnium and meitenerium for elements 108 and 109 respectively, commemorating them both. In the event, element 108 was named hessium, but element 109 was officially named meitnerium.</p>
<p>As Feste remarks in Twelfth Night, “And thus the whirligig of time brings in his revenges.” </p>
<p>All you have to do now is start revising.</p><img src="https://counter.theconversation.com/content/60841/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Cotton does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>As four new chemical elements are named, here’s all you need to know.Simon Cotton, Senior Lecturer in Chemistry, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/602762016-06-09T12:03:21Z2016-06-09T12:03:21ZFour new elements named – here’s how the periodic table evolved<p>The seventh row of the periodic table is complete, resplendent with <a href="http://iupac.org/cms/wp-content/uploads/2016/06/names-and-symbols-of-elements.pdf">four new names for the elements 113, 115, 117 and 118</a>. The International Union of Pure and Applied Chemistry (the organisation charged with naming the elements) has suggested these should be called nihonium (Nh); moscovium (Mc); tennessine (Ts) and oganesson (Og) and is expected to confirm the proposal in November.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/125867/original/image-20160609-7074-ypayh2.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/125867/original/image-20160609-7074-ypayh2.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=911&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125867/original/image-20160609-7074-ypayh2.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=911&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125867/original/image-20160609-7074-ypayh2.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=911&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125867/original/image-20160609-7074-ypayh2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1145&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125867/original/image-20160609-7074-ypayh2.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1145&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125867/original/image-20160609-7074-ypayh2.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1145&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Yuri Oganesyan.</span>
<span class="attribution"><span class="source">Kremlin.ru</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The three former elements are named after the regions where they were discovered (and Nihonium references <em>Nihon</em> the Japanese name for Japan). And “oganesson” is named after the Russian-American physicist Yuri Oganessian, who helped discover them.</p>
<p>After years of having to make do with temporary monikers while the elements were officially being added to the periodic table and evaluated by the IUPAC, these new names are much welcomed by scientists. Alas, those calling for names in tribute to great folk of popular culture have gone unheeded; <a href="https://thechronicleflask.wordpress.com/2016/01/06/name-element-117-octarine-in-honour-of-terry-pratchetts-discworld/">Octarine</a> (the colour of magic, according to Terry Pratchett), <a href="http://blog.oxforddictionaries.com/2016/01/new-chemical-elements-names/">Ziggium</a> (in tribute to David Bowie’s alter ego Ziggy Stardust) and Severium (in tribute to Alan Rickman and via Severus Snape) will not adorn the updated table. </p>
<p>Instead IUPAC have followed <a href="http://www.sciencealert.com/these-are-the-complicated-rules-that-dictate-how-new-elements-are-named">their rules</a> which stipulate that “elements are named after a mythological concept or character (including an astronomical object); a mineral, or similar substance; a place or geographical region; a property of the element; or a scientist”.</p>
<p>But there wasn’t always such an organisation overseeing the names of the elements. Most of them have come about <a href="http://pubs.acs.org/doi/abs/10.1021/ed064p472.4">via contorted etymologies</a>. So to give you an idea of the diversity of the most famous of scientific tables, I’ve turned it into an infographic and summarised a few of the eytmologies in numbers. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125802/original/image-20160608-3485-pb9zno.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Periodic Table of Elements’ Etymology.</span>
<span class="attribution"><span class="source">Andy Bruning, Compound Interest</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p><em><a href="https://universityofhull.box.com/s/03y9vjlwd8e2uekedb5wum98vl42597l" target="_blank">Click here for a larger version.</a></em></p>
<p><strong>Two</strong> of the elements stink. Bromine means “stench” and osmium means “smells”. France also appears twice on the periodic table in the form of francium and gallium (from Gaul) and its capital city, Paris, gets a mention (in the form of lutetium).</p>
<p><strong>Three</strong> sanskit words – <em>eka</em>, <em>dvi</em> and <em>tri</em>, meaning one, two and three – were prefixed to elements and used as provisional names for those that had yet to be discovered. Eka- is used to denote an element directly below another in the table, dvi- is for an element two rows down and tri- is three rows beneath. Russian chemist <a href="http://www.bbc.co.uk/schools/gcsebitesize/science/add_edexcel/atomic_structure/periodictablerev1.shtml">Dimitri Mendeleev</a> first used this nomenclature to fill in the gaps in his early periodic table, so element number 32 was known as eka-silicon until it was discovered and named germanium in 1886. Similarly, rhenium was known as dvi-manganese until 1926. Some 14 elements have had eka names including our four new additions which before their discovery were known as eka-thallium, eka-bismuth, eka-astitine and eka-radon.</p>
<p><strong>Four</strong> of the elements are named after planets (Earth – in the form of tellurium, Mercury, Neptune and Uranus). A further two are named after dwarf plants (Pluto and Ceres), while one after a star (helium from the Greek for the sun - Helios) and another after an asteroid (Pallas) feature on the periodic table. </p>
<p><strong>Five</strong> elements are named after other elements: molybdenium is from the Greek for lead, <em>molybdos</em>, while platinum comes from the Spanish <em>platina</em> meaning “little silver”. Radon is derived from radium, zirconium has its roots in the Arabic <em>zarkûn</em> meaning “gold-like” and nickle is from the German for “devil’s copper”.</p>
<p><strong>Eight</strong> elements were first isolated from rocks quarried in a the small village of Ytterby in Sweden. Four of those elements are named in tribute to the village (ytterbium, erbium, terbium, yttrium).</p>
<p><strong>15</strong> are named after scientists, only two of whom were women: Marie Curie and Lise Meitner are immortalised in curium and meitnerium.</p>
<p><strong>18</strong> elements have had placeholder names derived from the Latin for the elements atomic number (for example ununoctium, now oganesson). This was introduced to stop scientists fighting over what their discoveries should be called. Nobody wants a repeat of the three-decade long “<a href="http://www.academia.edu/3929798/The_Transfermium_Wars_IUPAC_and_the_Discovery_and_Naming_of_the_Transfermium_Elements">Transferium Wars</a>” when battles raged between competing American and Russian laboratories over what to call elements 104, 105 and 106. </p>
<p><strong>42</strong> elements’ names are derived from Greek; 23 from Latin; 11 from English; five are Anglo-saxon; five German; five Swedish; two Norse; three Russian, and one apiece for Japanese, Sanskrit, Gaelic, Arabic and Spanish.</p>
<p><strong>118</strong> elements appear on the periodic table, and the seventh row is complete, but that doesn’t mean the table is finished. Laboratories around the world are busy smashing atoms together in an attempt to <a href="http://www.wired.com/2016/01/smashing-new-elements-into-existence-gets-a-lot-harder-from-here/">forge new even heavier elements</a>. The hope is that before long these latter day alchemists will hit upon the fabled “<a href="http://arstechnica.com/science/2012/08/shell-game-why-heavier-atoms-might-get-stable-again/">island of stability</a>”; a region of the table that harbours elements with half-lives much longer that the sub-second lives of nihonium, moscovium, tennessine, and oganesson.</p>
<p>_Infographic for this article was made by Andy Brunning/<a href="http://www.compoundchem.com/2016/06/09/element-names/">Compound Interest</a></p><img src="https://counter.theconversation.com/content/60276/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Lorch is a member of the Royal Society of Chemistry.</span></em></p>Some 18 elements have had placeholder names derived from the Latin to stop scientists fighting over what their discoveries should be called.Mark Lorch, Professor of Science Communication and Chemistry, University of HullLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/528622016-01-07T05:46:10Z2016-01-07T05:46:10ZThe search for new elements on the periodic table started with a blast<figure><img src="https://images.theconversation.com/files/107484/original/image-20160107-14970-1tvxwlo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">New elements were discovered in early thermonuclear bomb tests.</span> <span class="attribution"><a class="source" href="https://pixabay.com/en/nuclear-weapons-test-nuclear-weapon-67557/">Pixabay</a></span></figcaption></figure><p>So the periodic table has expanded again with the addition late last year of <a href="https://theconversation.com/the-race-to-find-even-more-new-elements-to-add-to-the-periodic-table-52747">four new superheavy elements</a>, bringing the known total up to 118.</p>
<p>But the hunt for new elements started with efforts to develop nuclear power and the atomic bomb during World War II. At the time, <a href="http://www.rsc.org/periodic-table/element/92/uranium">uranium</a> was the heaviest known element, sitting at number 92 in the periodic table. </p>
<p>Researchers quickly discovered that when uranium is placed in a nuclear reactor, a complex sequence of interactions leads to the production of several so-called <a href="http://www.britannica.com/science/transuranium-element">transuranic elements</a> (elements beyond uranium).</p>
<p>Probing around in the debris of the first hydrogen bomb test revealed two further transuranic elements, <a href="http://www.rsc.org/periodic-table/element/99/einsteinium">einsteinium</a> and <a href="http://www.rsc.org/periodic-table/element/100/fermium">fermium</a>, bringing the total to an even 100. </p>
<p>Some of these elements are more commonly encountered that you might think. Most families would own some <a href="http://www.rsc.org/periodic-table/element/95/americium">americium</a> (element number 95) in the form of an every-day smoke detector, and <a href="http://www.rsc.org/periodic-table/element/98/californium">californium</a> (number 98) is widely used in industrial analysers. At a cool <a href="http://web.ornl.gov/%7Ewebworks/cpr/pres/107270_.pdf">US$60 million dollars per gram</a>, however, californium is about a million times more expensive than gold.</p>
<h2>Beyond the century element</h2>
<p>Beyond element 100, not even a hydrogen bomb is powerful enough to make progress, and scientists had to change tack in their quest for ever heavier elements. They substituted finesse for brute force, using particle accelerators to fire atoms onto carefully chosen targets. </p>
<p>Under the right conditions, the nuclei of atoms in the beam and target can fuse together and produce new elements. Fittingly, the first element made in this way, <a href="http://www.rsc.org/periodic-table/element/101/mendelevium">mendelevium</a>, was named after Dimitri Mendeleev, the creator of the periodic table.</p>
<p>Russian and American scientists continued to push forward through the 1950s, 60s and 70s, eventually reaching element <a href="http://www.rsc.org/periodic-table/element/106/seaborgium">106</a>. Reflecting the tensions of the Cold War years, priority for discovering these elements was strongly contested, with claims and counterclaims over ambiguous experimental results.</p>
<p>Not until 1997 did the International Union of Pure and Applied Chemistry (<a href="http://www.iupac.org/">IUPAC</a>) credit the discoverers of these elements and announce official names, mostly based on US and Soviet scientists and cities.</p>
<p>The Germans picked up the baton in the 1980s and 90s, discovering elements <a href="http://www.rsc.org/periodic-table/element/107/bohrium">107</a> through to <a href="http://www.rsc.org/periodic-table/element/112/copernicium">112</a>.</p>
<p>German researchers added a strongly European flavour to the naming scheme, honouring the physicists Niels Bohr (<a href="http://www.rsc.org/periodic-table/element/107/bohrium">bohrium</a>), Lise Meitner (<a href="http://www.rsc.org/periodic-table/element/109/meitnerium">meitnerium</a>), and Wilhelm Röntgen (<a href="http://www.rsc.org/periodic-table/element/111/roentgenium">roentgenium</a>), the astronomer Nicolaus Copernicus (<a href="http://www.rsc.org/periodic-table/element/112/copernicium">copernicium</a>) and their home city and state – <a href="http://www.rsc.org/periodic-table/element/110/darmstadtium">darmstadtium</a> and <a href="http://www.rsc.org/periodic-table/element/108/hassium">Hassium</a> are named after the town of Darmstadt and the German state of Hesse (passing through Latin along the way, which changes the ‘e’ to an ‘a’. Nothing’s ever simple!).</p>
<p>Only a handful of atoms of these elements have ever been produced.</p>
<h2>Let’s get super-heavy</h2>
<p>Moving on to still heavier elements, the hunt becomes increasingly difficult for three reasons.</p>
<p>First, the probability of two nuclei successfully fusing to form a new element rapidly decreases. Second, these super-heavy elements are extremely unstable, so any atoms produced have a fleeting existence. And third, it becomes increasingly difficult to untangle the complex signatures that reveal their momentary creation and decay.</p>
<p>Reflecting improved international relations in the post-Glasnost era, most of the recent discoveries have been credited to collaborations between US and Russian researchers. Elements 114 (<a href="http://www.rsc.org/periodic-table/element/114/flerovium">flerovium</a>) and 116 (<a href="http://www.rsc.org/periodic-table/element/116/livermorium">livermorium</a>) were announced by the IUPAC in 2012.</p>
<p>The <a href="http://www.iupac.org/news/news-detail/article/discovery-and-assignment-of-elements-with-atomic-numbers-113-115-117-and-118.html">most recent announcement</a> awards discovery of elements <a href="http://www.rsc.org/periodic-table/element/115/">115</a>, <a href="http://www.rsc.org/periodic-table/element/117/">117</a> and <a href="http://www.rsc.org/periodic-table/element/118/">118</a> to the same groups. A Japanese team, working independently, has been recognised for element <a href="http://www.rsc.org/periodic-table/element/113/">113</a>.</p>
<p>Producing even a sniff of these super-heavy elements is a heroic endeavour. To discover element 118, for example, experimenters fired a beam of calcium atoms for months at a time onto a target loaded with the element californium.</p>
<p>The odds of any one calcium atom fusing is tiny, roughly the same as winning the Oz Lotto jackpot, but then being killed by a lightning strike 15 minutes later.</p>
<p>The work resulted in just three atoms of the new element, each of which lasted for about 1000th of a second. Registering these atoms is just as difficult: a sophisticated detector system is need to pick up the cascade of radioactive decays which end with the atomic nucleus blowing itself apart.</p>
<h2>Why the search for new elements?</h2>
<p>All of which begs the question: why bother? After all, it’s hard to come up with a practical use for an element that takes so much effort to produce and lasts for so short a time.</p>
<p>Studying these super-heavy elements can teach us not only about the forces involved in atomic nuclei, but perhaps surprisingly, also about what goes on when stars die. </p>
<p>When a massive star explodes as a supernova, the extreme conditions could be just right for producing super-heavy elements. There are theoretical hints that some of these elements may buck the trend of increasing instability and exist in long-lived forms, an effect known as “<a href="http://www.superheavies.de/english/research_program/highlights_element_117.htm#The%20island%20of%20stability">the island of stability</a>”.</p>
<p>Current earth-bound experiments are just probing the shores of this island, but will help us determine whether these super-heavy elements could already be present in the universe. Searches in terrestrial rocks and in debris from space have so far drawn a blank, but researchers continue to hunt.</p>
<p>The four new additions to the periodic table have only temporary names at the moment. Rights for naming them go to the discoverers, although the IUPAC imposes strict rules.</p>
<p>Japonium has been suggested as a candidate for element 113, which would make it the first element starting with J. Now if scientists can just come up with a good name starting with Q, the periodic table would be alphabetically complete.</p><img src="https://counter.theconversation.com/content/52862/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Tickner does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>New elements found in the reactions of nuclear tests during World War II sparked the hunt for additions to the periodic table.James Tickner, Team Leader, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/527472016-01-05T05:58:20Z2016-01-05T05:58:20ZThe race to find even more new elements to add to the periodic table<figure><img src="https://images.theconversation.com/files/107236/original/image-20160105-28994-t3don9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The expanding periodic table of elements.</span> <span class="attribution"><span class="source">Shutterstock/Olivier Le Queinec</span></span></figcaption></figure><p>In an event likely never to be repeated, four new superheavy elements were last week <em>simultaneously</em> added to the periodic table. To add four in one go is quite an achievement but the race to find more is ongoing.</p>
<p>Back in 2012, the International Unions of Pure and Applied Chemistry (<a href="http://www.iupac.org/">IUPAC</a>) and Pure and Applied Physics (<a href="http://iupap.org/">IUPAP</a>) tasked five independent scientists to assess claims made for the discovery of elements 113, 115, 117 and 118. The measurements had been made at Nuclear Physics Accelerator laboratories in Russia (Dubna) and Japan (RIKEN) between 2004 and 2012. </p>
<p>Late last year, on December 30, 2015, IUPAC <a href="http://www.iupac.org/news/news-detail/article/discovery-and-assignment-of-elements-with-atomic-numbers-113-115-117-and-118.html">announced</a> that claims for the discovery of <em>all four</em> new elements had been accepted. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=329&fit=crop&dpr=1 600w, https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=329&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=329&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=413&fit=crop&dpr=1 754w, https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=413&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/30569/original/47ybnrd5-1378164128.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=413&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The completed seventh row in the periodic table.</span>
<span class="attribution"><span class="source">Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>This completes the seventh row of the periodic table, and means that all elements between hydrogen (having only one proton in its nucleus) and element 118 (having 118 protons) are now officially discovered.</p>
<p>After the excitement of the discovery, the scientists now have the naming rights. The Japanese team will suggest the name for element 113. The joint Russian/US teams will make suggestions for elements 115, 117 and 118. These names will be assessed by IUPAC, and once approved, will become the new names that scientists and students will have to remember.</p>
<p>Until their discovery and naming, all superheavy elements (up to 999!) have been assigned temporary names by the IUPAC. Element 113 is known as ununtrium (Uut), 115 is ununpentium (Uup), 117 is ununseptium (Uus) and 118 ununoctium (Uuo). These names are not actually used by physicists, who instead refer to them as “element 118”, for example.</p>
<h2>The superheavy elements</h2>
<p>Elements heavier than Rutherfordium (element 104) are referred to as superheavy. They are not found in nature, because they undergo radioactive decay to lighter elements.</p>
<p>Those superheavy nuclei that have been created artificially have decay lifetimes between nanoseconds and minutes. But longer-lived (more neutron-rich) superheavy nuclei are expected to be situated at the centre of the so-called “<a href="http://www.superheavies.de/english/research_program/highlights_element_117.htm#The%20island%20of%20stability">island of stability</a>”, a place where neutron-rich nuclei with extremely long half-lives should exist.</p>
<p>Currently, the isotopes of new elements that have been discovered are on the “shore” of this island, since we cannot yet reach the centre. </p>
<h2>How were these new elements created on Earth?</h2>
<p>Atoms of superheavy elements are made by nuclear fusion. Imagine touching two droplets of water – they will “snap together” because of surface tension to form a combined larger droplet. </p>
<p>The problem in the fusion of heavy nuclei is the large numbers of protons in both nuclei. This creates an intense repulsive electric field. A heavy-ion accelerator must be used to overcome this repulsion, by colliding the two nuclei and allowing the nuclear surfaces to touch. </p>
<p>This is not sufficient, as the two touching spheroidal nuclei must change their shape to form a compact single droplet of nuclear matter – the superheavy nucleus.</p>
<p>It turns out that this only happens in a few “lucky” collisions, as few as one in a million.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/YovAFlzFtzg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Superheavy reaction fails to fuse (ANU)</span></figcaption>
</figure>
<p>There is yet another hurdle; the superheavy nucleus is very likely to decay almost immediately by fission. Again, as few as one in a million survives to become a superheavy atom, identified by its unique radioactive decay. </p>
<p>The process of superheavy element creation and identification thus requires large-scale accelerator facilities, sophisticated magnetic separators, efficient detectors and <em>time</em>. </p>
<p>Finding the three atoms of element 113 in Japan took 10 years, and that was <em>after</em> the experimental equipment had been developed.</p>
<p>The payback from the discovery of these new elements comes in improving models of the atomic nucleus (with applications in nuclear medicine and in element formation in the universe) and testing our understanding of atomic relativistic effects (of increasing importance in the chemical properties of the heavy elements). It also helps in improving our understanding of complex and irreversible interactions of quantum systems in general.</p>
<h2>The Australian connection in the race to make more elements</h2>
<p>The race is now on to produce elements 119 and 120. The projectile nucleus Calcium-48 (Ca-48) – successfully used to form the newly accepted elements – has too few protons, and no target nuclei with more protons are currently available. The question is, which heavier projectile nucleus is the best to use. </p>
<p>To investigate this, the leader and team members of the German superheavy element research group, based in Darmstadt and Mainz, recently travelled to the Australian National University.</p>
<p>They made use of unique ANU <a href="http://physics.anu.edu.au/nuclear/hiaf.php">experimental capabilities</a>, supported by the Australian Government’s <a href="https://www.education.gov.au/national-collaborative-research-infrastructure-strategy-ncris">NCRIS program</a>, to measure fission characteristics for several nuclear reactions forming element 120. The results will guide future experiments in <a href="http://www-win.gsi.de/tasca/Default.htm">Germany</a> to form the new superheavy elements.</p>
<p>It seems certain that by using similar nuclear fusion reactions, proceeding beyond element 118 will be more difficult than reaching it. But that was the feeling after the discovery of element 112, first observed in 1996. And yet a new approach using Ca-48 projectiles allowed another six elements to be discovered. </p>
<p>Nuclear physicists are already exploring different types of nuclear reaction to produce superheavies, and some promising results have already been achieved. Nevertheless, it would need a huge breakthrough to see four new nuclei added to the periodic table at once, as we have just seen.</p><img src="https://counter.theconversation.com/content/52747/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Hinde receives funding from the Australian Research Council.</span></em></p>They might only last for a fraction of a second but four new elements have finally won their place in the periodic table. The hunt is now on to find even more.David Hinde, Director, Heavy Ion Accelerator Facility, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.