tag:theconversation.com,2011:/es/topics/aliens-5453/articlesAliens – The Conversation2024-01-21T23:31:52Ztag:theconversation.com,2011:article/2193962024-01-21T23:31:52Z2024-01-21T23:31:52ZThe Solar System used to have nine planets. Maybe it still does? Here’s your catch-up on space today<figure><img src="https://images.theconversation.com/files/566534/original/file-20231219-25-4dyqky.jpg?ixlib=rb-1.1.0&rect=31%2C15%2C5161%2C3230&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Some of us remember August 24 2006 like it was yesterday. It was the day Pluto got booted from the exclusive “planets club”.</p>
<p>I (Sara) was 11 years old, and my entire class began lunch break by passionately chanting “Pluto is a planet” in protest of the information we’d just received. It was a touching display. At the time, 11-year-old me was outraged – even somewhat inconsolable. Now, a much older me wholeheartedly accepts: Pluto is not a planet. </p>
<p>Similar to Sara, I (Rebecca) vividly remember Pluto’s re-designation to dwarf status. For me, it wasn’t so much that the celestial body had been reclassified. That is science, after all, and things change with new knowledge. Rather, what got to me was how the astronomy community handled the PR. </p>
<p>Even popular astronomers known for their public persona stumbled through mostly <a href="https://www.npr.org/templates/story/story.php?storyId=100145890">unapologetic explanations</a>. It was a missed opportunity. What was poorly communicated as a demotion was actually the discovery of new exciting members of our Solar System, of which <a href="https://www.loc.gov/everyday-mysteries/astronomy/item/why-is-pluto-no-longer-a-planet/">Pluto was the first</a>. </p>
<p>The good news is astronomers have better media support now, and there’s a lot of amazing science to catch up on. Let’s go over what you might have missed.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566535/original/file-20231219-19-8m96pv.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"></a>
<figcaption>
<span class="caption">Pluto didn’t meet the criteria of a fully fledged planet. But there may still be a 9th planet in our Solar System waiting to be found.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>A throwback to a shocking demotion</h2>
<p>Pluto’s fate was almost certainly sealed the day Eris was discovered in 2005. Like Pluto, Eris orbits in the outskirts of our Solar System. Although it has a smaller radius than Pluto, it has <a href="https://astronomy.swin.edu.au/cosmos/m/Mass">more mass</a>.</p>
<p>Astronomers concluded that discovering objects such as Pluto and Eris would only become more common as our telescopes became more powerful. They were right. Today there are five known <a href="https://theconversation.com/new-dwarf-planet-in-the-outer-solar-system-62354">dwarf planets</a> in the Solar System. </p>
<p>The conditions for what classifies a “planet” as opposed to a “dwarf planet” were <a href="https://science.nasa.gov/solar-system/planets/what-is-a-planet/">set by the International Astronomical Union</a>. To cut a long story short, Pluto wasn’t being targeted back in 2006. It just didn’t meet all three criteria for a fully fledged planet:</p>
<ol>
<li>it must orbit a star (in our Solar System this would be the Sun)</li>
<li>it must be big enough that gravity has forced it into a spherical shape</li>
<li>it must be big enough that its own gravity has cleared away any other objects of a similar size near its orbit.</li>
</ol>
<p>The third criterion was Pluto’s downfall. It hasn’t cleared its neighbouring region of other objects. </p>
<p>So is our Solar System fated to have just eight planets? Not necessarily. There may be another one waiting to be found. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ive-always-wondered-why-are-the-stars-planets-and-moons-round-when-comets-and-asteroids-arent-160541">I've always wondered: why are the stars, planets and moons round, when comets and asteroids aren't?</a>
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</em>
</p>
<hr>
<h2>Is there a Planet Nine out there?</h2>
<p>With the discovery of new and distant dwarf planets, astronomers eventually realised the dwarf planets’ motions around the Sun didn’t quite add up. </p>
<p>We can use complicated <a href="https://www.caltech.edu/about/news/caltech-researchers-find-evidence-real-ninth-planet-49523">simulations in supercomputers</a> to model how gravitational interactions would play out in a complex environment such as our Solar System. </p>
<p>In 2016, California Institute of Technology astronomers Konstantin Batygin and Mike Brown concluded – after modelling the dwarf planets and their observed paths – that mathematically there ought be a ninth planet out there.</p>
<p>Their <a href="https://www.caltech.edu/about/news/caltech-researchers-find-evidence-real-ninth-planet-49523">modelling</a> determined this planet would have to be about ten times the mass of Earth, and located some 90 billion kilometres away from the Sun (about 15 times farther then Pluto). It’s a pretty bold claim, and some remain sceptical.</p>
<p>One might assume it’s easy to determine whether such a planet exists. Just point a telescope towards where you think it is and look, right? If we can see galaxies billions of light years away, shouldn’t we be able to spot a ninth planet in our own Solar System?</p>
<p>Well, the issue lies in how (not) bright this theoretical planet would be. Best estimates suggest it sits at the depth limit of Earth’s largest telescopes. In other words, it could be 600 times fainter than Pluto.</p>
<p>The other issue is we don’t know exactly where to look. Our Solar System is <em>really</em> big, and it would take a significant amount of time to cover the entire sky region in which Planet Nine might be hiding. To further complicate things, there’s only a small window each year during which conditions are just right for this search. </p>
<p>That isn’t stopping us from looking, though. In 2021, a team using the Atacama Cosmology Telescope (a millimetre-wave radio telescope) published the results from their <a href="https://iopscience.iop.org/article/10.3847/1538-4357/ac2307">search for a ninth planet’s</a> movement in the outskirts of the Solar System. </p>
<p>While they weren’t able to confirm its existence, they provided ten candidates for further follow-up. We may only be a few years from knowing what lurks in the outskirts of our planetary neighbourhood.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566540/original/file-20231219-17-8m96pv.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 ACT sits at an altitude of 5,190 meters in Chile’s Atacama desert. Here, the lack of atmospheric water vapour helps to increase its accuracy.</span>
<span class="attribution"><a class="source" href="https://www.nist.gov/measuring-cosmos/atacama-cosmology-telescope">NIST/ACT Collaboration</a></span>
</figcaption>
</figure>
<h2>Finding exoplanets</h2>
<p>Even though we have telescopes that can reveal galaxies from the universe’s earliest years, we still can’t easily directly image planets outside of our Solar System, also called exoplanets. </p>
<p>The reason can be found in fundamental physics. Planets emit very dim red wavelengths of light, so we can only see them clearly when they’re reflecting the light of their star. The farther away a planet is from its star, the harder it is to see. </p>
<p>Astronomers knew they’d have to find other ways to look for planets in foreign star systems. Before Pluto was reclassified they had already detected the <a href="https://exoplanets.nasa.gov/resources/2084/greetings-from-your-first-exoplanet.">first exoplanet</a>, 51 Pegasi B, using a <a href="https://www.planetary.org/articles/color-shifting-stars-the-radial-velocity-method">radial velocity method</a>. </p>
<p>This gas giant world is large enough, and close enough to its star, that the gravitational tug of war between the two can be detected all the way from Earth. However, this method of discovery is tedious and challenging from Earth’s surface. </p>
<p>So astronomers came up with another way to find exoplanets: the transit method. When Mercury or Venus pass in front of the Sun, they block a small amount of the Sun’s light. With powerful telescopes, we can look for this phenomenon in distant star systems as well. </p>
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<a href="https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=619&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=619&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=619&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=778&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=778&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566539/original/file-20231219-15-rhodbm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=778&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">In August, the TESS telescope took this snapshot of the Large Magellanic Cloud (right) and the bright star R Doradus (left).</span>
<span class="attribution"><span class="source">NASA/MIT/TESS</span></span>
</figcaption>
</figure>
<p>We do this via the <a href="https://science.nasa.gov/mission/kepler">Kepler</a> space telescope and the Transiting Exoplanet Survey Satellite (<a href="https://science.nasa.gov/mission/tess">TESS</a>). Both have observed tens of thousands of stars and discovered thousands of new planets – dozens of which are about the same size as Earth. </p>
<p>But these observatories can only tell us a planet’s size and distance from its star. They can’t tell us if a planet <a href="https://theconversation.com/do-aliens-exist-we-asked-five-experts-161811">might be hosting life</a>. For that we’d need the James Webb Space Telescope.</p>
<h2>Looking for life</h2>
<p>The James Webb Space Telescope (JWST) has just wrapped up its first year and a half of science. Among its many achievements is the detection of molecules in the atmospheres of exoplanets, a feat made possible by the transit method. </p>
<p>One of these exoplanets, WASP-17, is also known as a “hot Jupiter”. It seems to have been plucked from a page in a sci-fi novel, with evidence for <a href="https://webbtelescope.org/contents/media/images/2023/140/01HC3B0DZNEMRQT3KQ6X4ZMNN2">quartz nanocrystals</a> in its clouds. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/10-times-this-year-the-webb-telescope-blew-us-away-with-new-images-of-our-stunning-universe-194739">10 times this year the Webb telescope blew us away with new images of our stunning universe</a>
</strong>
</em>
</p>
<hr>
<p>Meanwhile, the <a href="https://exoplanets.nasa.gov/what-is-an-exoplanet/planet-types/super-earth/">super-Earth</a> <a href="https://www.nasa.gov/universe/exoplanets/webb-discovers-methane-carbon-dioxide-in-atmosphere-of-k2-18-b/">K2-18b</a> (a Kepler find) shows signs of methane and carbon dioxide. But while such discoveries are amazing, the magic ingredient <a href="https://www.nhm.ac.uk/discover/eight-ingredients-life-in-space.html#:%7E:text=Liquid%20water%20is%20an%20essential,substances%20than%20most%20other%20liquids.">necessary for life</a> still eludes us: water vapour.</p>
<p>The field of planetary studies is evolving and 2024 looks promising. Maybe JWST will finally produce signs of water vapour in an exoplanet atmosphere. Who knows, we might even have a ninth planet surprise us all, filling the void left by Pluto. </p>
<p>Stay tuned for exciting science to come.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566536/original/file-20231219-21-vpjm.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"></a>
<figcaption>
<span class="caption">Small bodies on the very fringes of our Solar System are essentially invisible to us – but advanced new techniques and technologies are changing this.</span>
<span class="attribution"><span class="source">NASA/Jasmin Moghbeli</span></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/219396/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>When most of us left school there were still 9 planets – but we’ve come a long way since Pluto’s demotion. Here’s what’s next on the space agenda.Sara Webb, Lecturer, Centre for Astrophysics and Supercomputing, Swinburne University of TechnologyRebecca Allen, Coordinator Swinburne Astronomy Online | Program Lead of Microgravity Experimentation, Space Technology and Industry Institute, Swinburne University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2186582023-12-06T15:53:37Z2023-12-06T15:53:37ZUFOs: how astronomers are searching the sky for alien probes near Earth<p>There has been increased interest in unidentified flying objects (UFOs) ever since the Pentagon’s <a href="https://www.dni.gov/files/ODNI/documents/assessments/Prelimary-Assessment-UAP-20210625.pdf">2021 report</a> revealed what appears to be anomalous objects in US airspace, dubbed unidentified aerial phenomena (UAP). Fast forward to 2023, and Nasa <a href="https://www.nasa.gov/news-release/update-nasa-shares-uap-independent-study-report-names-director/">has already formed a panel</a> to investigate the reports and <a href="https://www.nytimes.com/2023/09/14/science/nasa-ufo-uap-report.html">appointed a director </a> for UAP research. </p>
<p>A <a href="https://www.aaro.mil/">newly founded Pentagon desk</a> has also released <a href="https://globalnews.ca/news/9746110/metallic-flying-orbs-nasa-pentagon-panel-ufos-uaps/">footage of mysterious metallic orbs</a>. What is perhaps most remarkable is that David Grusch, a former intelligence officer, testified under oath before the US Congress, stating that he had interviewed around 40 people involved <a href="https://thedebrief.org/intelligence-officials-say-u-s-has-retrieved-non-human-craft/">in secret programmes dealing with crashed UFOs</a>.</p>
<p>I am interested in searching the sky for alien, physical objects which may one day tell us whether we are alone in the galaxy. Consider this: within our own Milky Way galaxy, there are 40 billion Earth-sized, potentially habitable planets. </p>
<p>Human ingenuity has enabled us to engineer and launch probes like Voyager and Pioneer, capable of reaching the closest stars. We’ve initiated efforts such as the <a href="https://breakthroughinitiatives.org/initiative/3">Breakthrough Starshot programme</a> which aims to reach nearby star Alpha Centauri in just a few decades by exploring innovative propulsion methods. <a href="https://www.nature.com/articles/nature02884">Sending a probe may be more economical</a> than sending out radio or laser communication if there is no need to hurry.</p>
<p>If humans can send a probe to another star, why couldn’t another civilisation send a probe to our Solar System? Such a probe could make it to the <a href="https://arxiv.org/abs/1808.07024">main asteroid belt</a> and <a href="https://earthsky.org/space/alien-lurker-probes-co-orbital-asteroids-earth/">lurk on an asteroid</a>. </p>
<p>Or, it could make its way to the Earth, entering our atmosphere. If observed, it would be branded as a “UFO”. A civilisation capable of producing and sending probes could dispatch millions of them on exploratory missions throughout our galaxy.</p>
<p>Some may argue that such probes could only exist if they adhere to the laws of physics and engineering as we understand them today. However, humanity is a relatively young civilisation, and our knowledge is constantly evolving. </p>
<p>While humans have dreamt of flying for millennia as we gazed at the skies, it has only been 120 years since the Wright brothers achieved the first powered flight. That’s about as long ago as Albert Einstein published his theory of special relativity.</p>
<p>Is it really so difficult to imagine that a civilisation that is hundreds of thousands years older than ours might have learned more about the laws of physics or developed <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7514271/">a few more engineering tricks</a>?</p>
<p>If a civilisation <a href="https://theconversation.com/seti-why-extraterrestrial-intelligence-is-more-likely-to-be-artificial-than-biological-169966">were to evolve into artificial intelligence (AI)</a>, it might survive for millions of years. This could mean it would casually regard slow to a neighbouring star as nothing more than a leisurely stroll.</p>
<p>That said, few astronomers felt impressed by the <a href="https://www.youtube.com/watch?v=rO_M0hLlJ-Q">US Navy videos</a> or government reports. We need significantly better evidence and data than what has been presented so far.</p>
<h2>Unveiling UFOs</h2>
<p>How can we test whether there are extra terrestrial probes near Earth, and whether they can be tied to the possible UFO phenomenon? There are many options. Analysing materials from potentially crashed UFOs could give irrefutable proof. This <a href="https://www.sciencedirect.com/science/article/abs/pii/S0376042121000907?fr=RR-2&ref=pdf_download&rr=8303a873ba1235b9">would require state-of-the-art techniques</a> to determine if these wrecks exhibit exotic or distinctly different characteristics of manufacture.</p>
<p>Obtaining such exotic samples, if they indeed exist, may prove challenging – they are rumoured to be <a href="https://nypost.com/2021/04/30/former-sen-harry-reid-thinks-lockheed-martin-may-have-ufo-fragments/">in the hands of private companies</a>. But <a href="https://www.democrats.senate.gov/newsroom/press-releases/schumer-rounds-introduce-new-legislation-to-declassify-government-records-related-to-unidentified-anomalous-phenomena-and-ufos_modeled-after-jfk-assassination-records-collection-act--as-an-amendment-to-ndaa">newly proposed legislation</a> might offer a solution to that problem in United States by mandating that all artificial materials from any non-human intelligence be surrendered to the US government.</p>
<p>In the projects I lead, we are searching for artificial non-human objects by <a href="https://www.sciencedirect.com/science/article/pii/S0094576522000480">looking for short light flashes</a> in the night sky. Short flashes typically occur when a flat, highly reflective surface — such as a mirror or glass — reflects sunlight. It could, however, also result from an artificial object emitting its own internal light.</p>
<p>Such short light flashes sometimes repeat and follow a straight line as the object tumbles in space during its orbit around the Earth. This is why satellites often appear as repeating light flashes in images. </p>
<p>Historical photographic plates taken before the launch of Sputnik 1 in 1957 <a href="https://earthsky.org/space/9-weird-transients-palomar-observatory-1950/">have revealed</a> the presence of nine light sources (transients) that appear and vanish within an hour in a small image, defying <a href="https://www.nature.com/articles/s41598-021-92162-7">astronomical explanations</a>. In some cases, the transient light sources <a href="https://arxiv.org/abs/2204.06091">are even aligned</a>, just like when short flashes come from moving objects. </p>
<figure class="align-center ">
<img alt="Image of the three disappearing stars." src="https://images.theconversation.com/files/563920/original/file-20231206-23-e5jplo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/563920/original/file-20231206-23-e5jplo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=234&fit=crop&dpr=1 600w, https://images.theconversation.com/files/563920/original/file-20231206-23-e5jplo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=234&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/563920/original/file-20231206-23-e5jplo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=234&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/563920/original/file-20231206-23-e5jplo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=294&fit=crop&dpr=1 754w, https://images.theconversation.com/files/563920/original/file-20231206-23-e5jplo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=294&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/563920/original/file-20231206-23-e5jplo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=294&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The three disappearing stars.</span>
<span class="attribution"><a class="source" href="https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stad3422/7457759">[Edited, higher-resolution version of Fig 2 in paper by Solano et al. (2023)(https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stad3422/7457759)]</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The <a href="https://www.universetoday.com/163820/in-1952-a-group-of-three-stars-vanished-astronomers-still-cant-find-them/">most recent finding</a> of this kind shows three bright stars in an image dated July 19, 1952 (coincidentally, the same time as the famous <a href="https://en.wikipedia.org/wiki/1952_Washington,_D.C.,_UFO_incident">Washington UFO flyovers</a>). The three stars were never seen again.</p>
<p>Searching for alien probes in the modern night sky presents a serious but necessary challenge. A new research programme, <a href="https://thedebrief.org/a-new-era-of-optical-seti-the-search-for-artificial-objects-of-non-human-origin/">known as ExoProbe</a>, searches for short light flashes from potential alien objects with the help of multiple telescopes. </p>
<p>To verify the authenticity of each flash, it must be observed in at least two different telescopes. Since these telescopes are separated by hundreds of kilometres, any light flash caused by an object within the inner Solar System enables the measurement of parallax — the apparent shift in the position of an object as seen from two different points — and the calculation of the distance to the object. </p>
<p>The ExoProbe project also uses its own methods to filter out light flashes from the millions of space debris fragments and thousands of satellites cluttering the sky. By adding a telescope taking real-time spectra (the wavelength distributions of the light) of the objects in a wide field, you can analyse the transients before they vanish into nothingness.</p>
<p>Finally, increasing the number of telescopes further enhances accuracy in measuring parallax and determining the actual three dimensional location of the object. Ultimately, the goal is to identify any potential alien object and bring it back to Earth for further study. </p>
<p>Some 60 years of searches for extraterrestrial civilisations in the radio frequencies have yielded no candidates whatsoever. We find ourselves at a moment in time when new paths must be explored. That means we can finally focus our attention closer to home. Regardless of the outcome, this journey is certainly an homage to our insatiable curiosity.</p><img src="https://counter.theconversation.com/content/218658/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Beatriz Villarroel receives funding from a private donor for the ExoProbe project.</span></em></p>Several scientific projects are aiming to investigate UFO sightings.Beatriz Villarroel, Assistant professor of Physics, Stockholm UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2136152023-09-19T15:08:14Z2023-09-19T15:08:14ZUFOs: how Nasa plans to get to the bottom of unexplained sightings<figure><img src="https://images.theconversation.com/files/548386/original/file-20230914-29-c7oo4l.jpg?ixlib=rb-1.1.0&rect=8%2C17%2C5982%2C3350&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/ufo-concept-glowing-orbs-floating-above-1978082291">Raggedstone / Shutterstock</a></span></figcaption></figure><p>As reports continue flying in about what were traditionally called UFOs (unidentified flying objects), Nasa is taking the topic very seriously. In fact, following the publication of a report from an independent committee of experts in fields including astronomy and aviation safety, the agency has even appointed a new director of unidentified anomalous phenomena (UAP) research. </p>
<p>UAP is the term Nasa now uses for UFOs. <a href="https://science.nasa.gov/uap/">The committee was directed</a> to gather reports of UAPs and try to understand what these mysterious events really are, including answering the question of whether or not they could be extraterrestrial in origin. </p>
<p>The committee held a press conference <a href="https://theconversation.com/ufos-what-well-learn-from-the-nasa-panel-investigating-sightings-207328">back in May</a>, when it provided an update on its work up to that point. The study team outlined some of the common explanations for UAP sightings – which includes boats low on the horizon and high-flying balloons – as well as how many events remained truly unexplained. </p>
<p>Now, the committee has published the full report into what it has found, including recommendations for Nasa as its work continues. That report, which also contains Nasa’s response and plan as it moves forward, <a href="https://science.nasa.gov/science-pink/s3fs-public/atoms/files/UAP%20Independent%20Study%20Team%20-%20Final%20Report_0.pdf">can be read in full here</a>. I’ve also <a href="https://youtu.be/hUtH1r3o7VA">created a video</a> about the findings. </p>
<p>The report makes clear that, so far, the committee has absolutely no evidence that any of the reported UAP events have any involvement from aliens. But for the reports that are still unexplained by terrestrial phenomena or aircraft, the team doesn’t rule anything out. It makes it clear that an extraterrestrial origin is unlikely, but that it has no evidence at all for what these sightings are. </p>
<p>The rest of the report deals with how Nasa should respond to the findings, and what it plans to do to continue this research in future. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ufos-what-well-learn-from-the-nasa-panel-investigating-sightings-207328">UFOs: what we'll learn from the Nasa panel investigating sightings</a>
</strong>
</em>
</p>
<hr>
<h2>Need for transparency</h2>
<p>The most substantial response has been the appointment of the director of UAP research – a brand new role. Initially, when announcing this, Nasa refused to name the person in the role. It hoped to shield the new UAP director from the kind of harassment that some members of the committee have received for their involvement in the research.</p>
<p>However, the space agency also pledged to be completely transparent about the work on UAPs and everything it finds. This philosophy seems to have prevailed, and Nasa later announced that the <a href="https://www.space.com/nasa-names-head-of-uap-research">new director would be Mark McInerney</a>, a previous Nasa liaison to the US Department of Defense. </p>
<figure class="align-center ">
<img alt="Representation of UFOs." src="https://images.theconversation.com/files/548382/original/file-20230914-17-54dkao.jpg?ixlib=rb-1.1.0&rect=940%2C407%2C2982%2C1754&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548382/original/file-20230914-17-54dkao.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548382/original/file-20230914-17-54dkao.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548382/original/file-20230914-17-54dkao.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548382/original/file-20230914-17-54dkao.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548382/original/file-20230914-17-54dkao.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548382/original/file-20230914-17-54dkao.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">
<figcaption>
<span class="caption">A representation of UFOs.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/amazing-fantastic-background-extraterrestrial-aliens-spaceship-1461851036">IgorZH / Shutterstock</a></span>
</figcaption>
</figure>
<p>Nasa also put forward the idea of developing a smartphone app to aid with the future reporting of UAPs. While there are hundreds of sightings available for study by the committee, one persistent problem it has faced is <a href="https://www.nbcnews.com/science/ufos-and-aerial-phenomena/nasa-ufo-unidentified-aerial-phenomena-panel-hearing-rcna87034">poor data and images</a>.</p>
<p>Nasa hopes to combat this issue for future reports by using the billions of high-tech detectors around the world that most people carry everywhere. Smartphones can collect a lot of high quality information, starting with photos and videos, but they can also gather data on <a href="https://gizmodo.com/all-the-sensors-in-your-smartphone-and-how-they-work-1797121002">gravity, magnetic fields, locations and more</a>. If the general public were open to the idea, Nasa would like to one day allow people to report sightings directly from their phones to the agency. </p>
<p>Another interesting revelation in the report is the prominence that Nasa believes artificial intelligence (AI) and machine learning could have as this work continues. Looking for patterns in the UAP reports – such as geographical reporting hotspots – could hold the key to finally understanding the causes of some of the events that remain mysterious.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/hUtH1r3o7VA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Chris Pattison explains the findings of the Nasa report on UAPs.</span></figcaption>
</figure>
<p>Pattern spotting is something that humans are very good at, but sometimes the common thread is so subtle and unexpected that people can’t spot it. Luckily, AI is getting better and more powerful, and pattern spotting is <a href="https://www.forbes.com/sites/cognitiveworld/2020/05/09/understanding-the-recognition-pattern-of-ai/">one of the things it excels at</a>. This raises the interesting possibility that AI could be essential in one day identifying the first evidence for extraterrestrial life visiting Earth. It’s not likely that we’ll identify aliens, but Nasa isn’t ruling it out. </p>
<p>The week that this report was released turned out to be a busy week for discussions about aliens. In Mexico, a journalist named Jaime Maussan <a href="https://www.theguardian.com/world/2023/sep/13/mexican-senate-hearing-ufos">presented alleged “mummified aliens”</a> to the country’s Congress that he claimed had been found in Peru. </p>
<p>He said the specimens contained non-human DNA, but this has <a href="https://www.bbc.co.uk/news/av/world-66853551">not yet been independently verified</a>. In fact, <a href="https://www.independent.co.uk/news/world/americas/aliens-mexico-congress-ufos-b2412522.html">much doubt</a> has been cast <a href="https://www.wired.com/story/mexico-congress-aliens-fake/">over the authenticity</a> of these corpses.</p>
<p>In both cases, the world must wait longer to get more concrete evidence. As more reports are collected by Nasa, it might be possible to get more clarity on what these strange objects are. And if independent testing of the Mexico specimens takes place, there might be a conclusion to this claim too.</p><img src="https://counter.theconversation.com/content/213615/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Pattison 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>The space agency hopes to get to the bottom of the many sightings being reported.Christopher Pattison, Researcher at the Institute of Cosmology and Gravitation, University of PortsmouthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2131042023-09-11T15:42:17Z2023-09-11T15:42:17ZHow to prove you’ve discovered alien life – new research<figure><img src="https://images.theconversation.com/files/547466/original/file-20230911-28-wkdmi6.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C498%2C498&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In 2021, scientists thought they had discovered phosphine in the clouds of Venus.</span> <span class="attribution"><a class="source" href="https://photojournal.jpl.nasa.gov/catalog/PIA00270">NASA</a></span></figcaption></figure><p>In the past few decades, <a href="https://www.businessinsider.com/times-scientists-thought-they-discovered-extraterrestrial-alien-life-signs-2023-2?r=US&IR=T">several phenomena</a> have led to excited speculation in the scientific community that they might indeed be indications that there is extraterrestrial life. It will no doubt happen again. </p>
<p>Recently, two very different examples sparked excitement. In 2017, it was the mystery interstellar object <a href="https://theconversation.com/evidence-of-aliens-what-to-make-of-research-and-reporting-on-oumuamua-our-visitor-from-space-106711">‘Oumuamua</a>. And in 2021, it was the <a href="https://theconversation.com/venus-could-it-really-harbour-life-new-study-springs-a-surprise-145981">possible discovery of the gas phosphine</a> in the clouds of Venus.</p>
<p>In both cases, it seemed possible that the phenomenon indicated some kind of extraterrestrial biological source. Notably, physicist Avi Loeb from Harvard University <a href="https://theconversation.com/has-earth-been-visited-by-an-alien-spaceship-harvard-professor-avi-loeb-vs-everybody-else-155509">argued in favour</a> of the oddly shaped ‘Oumuamua being an alien spaceship. </p>
<p>And phosphine in the atmosphere of a rocky planet is <a href="https://www.liebertpub.com/doi/full/10.1089/ast.2018.1954">proposed to be</a> a strong signature for life, as it is continuously produced by microbes on Earth. </p>
<p>These are just two of the latest cases of a long list of examples of such initially promising phenomena. But although a few of the examples are still controversial, most have turned out to have other explanations (it wasn’t aliens).</p>
<p>So how can we be sure we’ve come to the right conclusion for something as subtle as the presence of a certain gas or a strange looking space rock? In our new paper <a href="https://www.liebertpub.com/doi/abs/10.1089/ast.2022.0084">published in the journal Astrobiology</a>, we have proposed a technique for reliably evaluating such evidence. </p>
<p>The word “possible” is strange, with a rather unfortunate degree of flexibility. There’s a sense in which it is possible that I’ll meet King Charles III today, but at the same time it is extraordinarily unlikely. </p>
<p>Many shouts of: “It might be aliens!” should be interpreted in this (strained) sense. By contrast, we often use the word “might” to express something that has high probability, as in “it might snow today.”</p>
<p>The concept of possibility incorporates these extremes, and everything in-between. Newspapers might capitalise on this flexibility with a cheeky headline that appears to indicate that something is a bit more exciting than it actually is. But the scientific world needs to express itself with rigour, transparently conveying the degree of confidence justified by the evidence.</p>
<p>Some would turn to <a href="https://theconversation.com/ufos-how-to-calculate-the-odds-that-an-alien-spaceship-has-been-spotted-162269">Bayes’ Theorem</a>, a common statistical formula, which gives the probability (Pr) of something, given some evidence. </p>
<p>One could, optimistically, input the available evidence into the Bayes formula, and achieve as output a number between 0 and 1 (where 0.5 is a 50:50 chance that a signal is produced by aliens). But the Bayesian approach doesn’t really help when it comes to extraterrestrial life. </p>
<figure class="align-center ">
<img alt="Image of the Bayesian formula." src="https://images.theconversation.com/files/404772/original/file-20210607-23-2oywyc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/404772/original/file-20210607-23-2oywyc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=79&fit=crop&dpr=1 600w, https://images.theconversation.com/files/404772/original/file-20210607-23-2oywyc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=79&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/404772/original/file-20210607-23-2oywyc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=79&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/404772/original/file-20210607-23-2oywyc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=100&fit=crop&dpr=1 754w, https://images.theconversation.com/files/404772/original/file-20210607-23-2oywyc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=100&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/404772/original/file-20210607-23-2oywyc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=100&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Bayesian formula for alien evidence, produced by Anders Sandberg, University of Oxford.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For example, it requires an input for the prior probability that aliens exist. And intuitions about that vary dramatically (estimates for the number of inhabited planets in our galaxy <a href="https://www.forbes.com/sites/jamiecartereurope/2021/06/23/there-is-only-one-other-planet-in-our-galaxy-that-could-be-earth-like-say-scientists/">range from one to billions</a>). </p>
<p>It also requires a value for the probability of the phenomenon in question occurring naturally – not caused by aliens. For some kinds of “biosignatures” (such as a dinosaur skeleton) we know that the probability of it occurring without life is incredibly low. But for many others (say, a particular blend of gases) we don’t know much at all. </p>
<figure class="align-center ">
<img alt="Diagram of how much possibility space we have explored." src="https://images.theconversation.com/files/546969/original/file-20230907-20-2t155l.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546969/original/file-20230907-20-2t155l.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=310&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546969/original/file-20230907-20-2t155l.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=310&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546969/original/file-20230907-20-2t155l.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=310&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546969/original/file-20230907-20-2t155l.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=389&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546969/original/file-20230907-20-2t155l.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=389&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546969/original/file-20230907-20-2t155l.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=389&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">How much of the relevant possibility space have we explored?</span>
<span class="attribution"><span class="source">Peter Vickers</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Here one meets with <a href="https://global.oup.com/academic/product/exceeding-our-grasp-9780195174083?cc=gb&lang=en&">the problem of “unconceived alternatives”</a>. Put simply: we may know too little about alternative sources of the phenomenon. Perhaps we just haven’t explored the space of possible causes of the relevant phenomenon very much. </p>
<p>After all, humans have only carried out a limited amount of rigorous research – we don’t know about every single process that could produce a certain gas in an atmosphere.</p>
<h2>New approaches</h2>
<p>In 2021, a Nasa-affiliated group <a href="https://www.nature.com/articles/s41586-021-03804-9.epdf?sharing_token=aMvAzNSKTDpeQ_Lx50lBO9RgN0jAjWel9jnR3ZoTv0OiHZ7kRMaxJS4ikXfsEfuhWNXQC4W7SsC52JCjUDnSSqLC5BhXbWxxUcFJQ3KnlmY6LAuQF02dgmfPAEQqFuQhHT7iq8uOqnhGqUWJGAFWKU9xwVrg8ofZtBSQm0hNMoQ%3D">published a paper</a> setting out the Confidence of Life Detection (CoLD) framework, designed to solve this problem.</p>
<p>It recommends seven steps to verifying a discovery, from ruling out contamination to getting follow-up observations of a predicted biological signal in the same region.</p>
<p>Unfortunately, the problem of unconceived alternatives remains a serious challenge. Level 4 in the framework requires that “all known non-biological sources of signal” are shown to be implausible. But this only starts to mean something when the relevant space of different possibilities has been thoroughly explored. </p>
<p>Our new paper, published by the group <a href="https://www.durham.ac.uk/research/institutes-and-centres/humanities-engaging-science-society/research/eurica-project-leverhulme/">Exploring Uncertainty and Risk in Contemporary Astrobiology</a> (EURiCA), has come up with another proposal.</p>
<p>Or, rather, it is an idea borrowed from another context. For many years, it has been imperative for the Intergovernmental Panel on Climate Change (IPCC) to be clear on how confident they are concerning a great many propositions about climate change. </p>
<p>In order to express their degree of confidence, <a href="https://www.ipcc.ch/site/assets/uploads/2017/08/AR5_Uncertainty_Guidance_Note.pdf">a framework has been in place</a> for more than 20 years now, which combines the quantity and quality of the evidence with the degree to which experts agree (the degree of consensus, if any). While this has been robustly challenged, it has stood the test of time in the face of extraordinary scrutiny and the highest possible stakes. </p>
<p>This same framework could be used in the context of discovering extraterrestrial life. A dedicated team of experts would make a judgement based not only on their assessment of the scientific evidence (X-axis in image above), but also the extent of agreement across the community (Y-axis). </p>
<p>So the worst assessment would have low agreement among experts and limited evidence while the best would have high agreement and robust evidence. </p>
<p>What of unconceived alternatives? The community of experts will only agree that purported evidence for life is “robust” if the relevant possibilities have been thoroughly explored. If they haven’t, there’s a good chance some other explanation will turn up in the long run. </p>
<p>Astrobiologists mustn’t limit their research to the study of the signatures of life. They must also carefully investigate the possible ways that non-biological processes might mimic those same signatures. </p>
<p>Only when we know that, might we finally be able to say, “This time, it really could be aliens.”</p><img src="https://counter.theconversation.com/content/213104/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Peter Vickers receives funding from Leverhulme Trust Research Project Grant (RPG-2021-274).</span></em></p><p class="fine-print"><em><span>Sean McMahon receives funding from Leverhulme Trust Research Project Grant (RPG-2021-274) and the Royal Society of Edinburgh grant #1918.</span></em></p>Alien hunters should learn from the Intergovernmental Panel on Climate Change (IPCC).Peter Vickers, Professor in Philosophy of Science, Durham UniversitySean McMahon, Chancellor's Fellow in Astrobiology, The University of EdinburghLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2127892023-09-06T12:07:36Z2023-09-06T12:07:36ZHave we really found the first samples from beyond the Solar System? The evidence is not convincing<figure><img src="https://images.theconversation.com/files/546217/original/file-20230904-27-c5k7ta.jpg?ixlib=rb-1.1.0&rect=89%2C89%2C4167%2C2744&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/pacific-ocean-view-santa-monica-pier-345950342">Frank Romeo/Shutterstock</a></span></figcaption></figure><p>Avi Loeb, an astrophysicist at Harvard University in the US, has published a <a href="https://projects.iq.harvard.edu/galileo/news/spherule-analysis-finds-evidence-extrasolar-composition">press release</a> claiming that some of the 700 or so spherical metallic fragments (spherules) <a href="https://theconversation.com/physicist-who-found-spherical-meteor-fragments-claims-they-may-come-from-an-alien-spaceship-heres-what-to-make-of-it-209101">he recovered</a> from the bottom of the Pacific Ocean, just off the coast of Papua New Guinea, are from beyond the Solar System.</p>
<p>The discovery was quite interesting because, although such spherules are distributed globally, it is not easy to recover them from the depths of the ocean bed – requiring a dredging operation with a powerful magnet. But Loeb has speculated that the spherules may be related to the passage of an interstellar meteor, IM1, which burned up over the South Pacific Ocean in January, 2014. He has even hypothesised that the spherules are actually debris from an alien spacecraft. I commented at the time that <a href="https://theconversation.com/physicist-who-found-spherical-meteor-fragments-claims-they-may-come-from-an-alien-spaceship-heres-what-to-make-of-it-209101">I’d need firm analytical evidence</a> to accept such interpretations. </p>
<p>Loeb has now provided a very <a href="https://arxiv.org/abs/2308.15623">detailed set of analytical data</a> of 57 spherules in an article submitted to a journal. But it has not yet been subject to the peer review that academics require before they accept research as legitimate. However, the paper has been subject to <a href="https://twitter.com/Deschscoveries/status/1697538023666397513">much scrutiny</a> on social media.</p>
<figure class="align-center ">
<img alt="Loeb next to image of spherule" src="https://images.theconversation.com/files/536316/original/file-20230707-21-5ea08a.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536316/original/file-20230707-21-5ea08a.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=307&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536316/original/file-20230707-21-5ea08a.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=307&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536316/original/file-20230707-21-5ea08a.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=307&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536316/original/file-20230707-21-5ea08a.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=385&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536316/original/file-20230707-21-5ea08a.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=385&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536316/original/file-20230707-21-5ea08a.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=385&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Loeb next to image of spherule.</span>
<span class="attribution"><span class="source">NewsNation/Youtube</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Loeb’s analyses were carried out using well known techniques and state-of-the art equipment, so there are no concerns that the analyses are faulty. Indeed, most of the spherules do appear to come from outside our own planet, as shown by their abundances of elements such as nickel, magnesium and manganese, which match those of meteorites. </p>
<p>Such particles are referred to as “cosmic spherules” and normally come from asteroids within our Solar System. Loeb’s material is, in fact, similar in nature to cosmic spherules <a href="https://www.sciencedirect.com/science/article/pii/S0016703717305495">that have been found</a> in sediments and ice cores. </p>
<p>A few of the spherules stand out because they have more unusual elemental compositions. These are named “BeLaU” particles by Loeb because they are rich in beryllium, lanthanum and uranium. Loeb rules out them being natural, terrestrial material, or extraterrestrial material from within the Solar System, on the basis of their iron isotope compositions. Isotopes are versions of an element with the same number of particles called protons in the nucleus, but different numbers of particles called neutrons, giving them different atomic masses. </p>
<p>His conclusions are a little inconsistent. The BeLaU spherules do indeed have a very different iron isotopic composition from some terrestrial and Solar System bodies, specifically those that have been through the process of melting and cooling as they formed. In other words, they do not match planetary objects, such as the Earth, Mars or the Moon. But that does not rule out their coming from bodies that have not been through a planetary formation process, such as the asteroids from which cosmic spherules originate.</p>
<p>Most cosmic spherules have been produced by ablation, the process by which material is eroded from a surface by friction. The friction is generated by interaction with air as a meteorite passes through the atmosphere at high velocity. This imparts unusual iron isotope compositions to the particles. The BeLaU spherules have iron isotope compositions in the same range as cosmic spherules. This could imply that they are indeed from within the Solar System. </p>
<p>Although Loeb acknowledges this, he still concludes that the BeLaU material has an interstellar origin.</p>
<h2>Other explanations</h2>
<p>It is interesting to join Loeb and speculate on potential origins for the spherules. In his paper, he says the samples “could have originated from a highly differentiated magma ocean of a planet with an iron core outside the solar system or from more exotic sources”. This is unlikely – iron meteorites from within the Solar System are the most affected by melting and do not have similar compositions to the BeLaU spherules.</p>
<p>Other possibilities that Loeb considers are supernovas (infinitely hot exploding stars) and cool, luminous stars (known as “asymptotic giant branch” stars, where cool is still incredibly hot). A supernova results from the catastrophic implosion of a stellar source, producing bursts of neutrons to form new elements. </p>
<p>The isotopic composition of those elements has been measured in many grains found in meteorites. Such grains are older than the Sun and could be regarded as interstellar. But they differ from the spherules described by Loeb because they are very small – only a few microns at most. Loeb’s samples are millimetre to centimetre sized. </p>
<p>I have another, equally speculative, suggestion. The Marshall Islands are only a few hundred kilometres or so from the region where Loeb searched. The Islands were the site of <a href="https://ahf.nuclearmuseum.org/ahf/location/marshall-islands/">67 nuclear tests</a> by the US between 1946 and 1958, causing radiation damage. The spherules could be fallout from these tests – a type of human-generated supernova. </p>
<figure class="align-center ">
<img alt="Marshall islands nuclear test." src="https://images.theconversation.com/files/546216/original/file-20230904-15-zdhoxe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546216/original/file-20230904-15-zdhoxe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546216/original/file-20230904-15-zdhoxe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546216/original/file-20230904-15-zdhoxe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546216/original/file-20230904-15-zdhoxe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546216/original/file-20230904-15-zdhoxe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546216/original/file-20230904-15-zdhoxe.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">Marshall islands nuclear test.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/File:Castle_Bravo_Blast.jpg">United States Department of Energy</a></span>
</figcaption>
</figure>
<p>I think there are more analyses that could be done to test Loeb’s hypothesis. For example: look for spherules in the beach sands and ocean floor around Bikini Atoll and Enewetak, where the nuclear tests took place.</p>
<p>Another obvious test is to measure the oxygen isotopic composition of the spherules. This parameter is based on the three stable isotopes of oxygen. The ratios between those can be used to conclusively determine whether material is terrestrial or extraterrestrial. </p>
<p>An oxygen isotope signature can be traced even following weathering and alteration of samples. Similarly, it would be informative to see whether there are gases trapped in the spherules. Analysis of noble gases (especially xenon) in the spherules could indicate if they came from a supernova or other type of star. </p>
<p>Assuming the spherules are not radioactive, I would be happy to facilitate their analysis. Our <a href="https://www.open.ac.uk/research/engagement/facilities">laboratories at The Open University</a> specialise in the analysis of miniscule amounts of extraterrestrial material, specifically in <a href="https://www.nature.com/articles/s41550-022-01824-7">oxygen isotope composition</a>. We also have a long history of analysis of <a href="https://iopscience.iop.org/article/10.1086/507176">xenon in interstellar grains</a>.</p>
<p>I am afraid that I come to the same conclusion that I did last time: Loeb has recovered some interesting particles, but none of the evidence he presents is sufficiently convincing to infer that the materials are either connected with IM1, or are from an alien spaceship.</p><img src="https://counter.theconversation.com/content/212789/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Monica Grady is Professor of Planetary and Space Sciences at the Open University, Chancellor of Liverpool Hope University and Honorary Senior Research Fellow at The Natural History Museum. She receives funding from the Science and Technology Facilities Council and the UK Space Agency. She tweets as @MonicaGrady</span></em></p>Could spherical metallic fragments be from a nuclear test?Monica Grady, Professor of Planetary and Space Sciences, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2034942023-08-14T12:23:14Z2023-08-14T12:23:14ZWhat is most likely going on in Area 51? A national security historian explains why you won’t find aliens there<figure><img src="https://images.theconversation.com/files/536155/original/file-20230706-19-6ho7f4.jpg?ixlib=rb-1.1.0&rect=0%2C13%2C4608%2C3435&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">For decades, what lay at the end of this road was a mysterious secret.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Area_51_Main_Gate.jpg">David James Henry/Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>What is most likely going on in Area 51? – Griffin, age 10, South Lyon, Michigan</strong></p>
</blockquote>
<hr>
<p>One of the reasons people can never be entirely sure about what is going on at Area 51 is that it is a highly classified secret military facility. It was not until 2013 that the U.S. government even acknowledged the existence and name “Area 51.” </p>
<p>This information came out as part of a broader set of documents released through a <a href="https://www.foia.gov/about.html">Freedom of Information Act</a> request, which is something regular citizens and groups can do to ask the U.S. government to provide details about government activities. In this case, the request made public formerly classified CIA information regarding the historical development and testing of the U-2 spy plane. The information also revealed where it was tested: Area 51!</p>
<p>As a <a href="https://www.researchgate.net/scientific-contributions/Christopher-McKnight-Nichols-2119126815">national security historian</a>, I know there’s a long history of secrets at Area 51. I also know that none of those secrets have anything to do with space aliens.</p>
<h2>The place</h2>
<p>The base commonly referred to as Area 51 is located in a remote area of southern Nevada, roughly 100 miles (161 kilometers) from Las Vegas. It is in the middle of a federally protected area of the U.S. Air Force’s Nevada Test and Training Range, now known as the <a href="https://www.nnss.gov/">Nevada National Security Site</a>, which is inside the larger Nellis Air Force Range. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a map showing the city of Las Vegas in the bottom right corner and an inset of the United States in the bottom left corner with Southern Nevada highlighted" src="https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/535094/original/file-20230630-27-ten4o0.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Area 51, the yellow rectangle in the center of the map, is tucked in the middle of the much larger Nellis Air Force Range.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Wfm_area51_map_en.png">DEMIS BV via Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Area 51 is the name on maps for the area within the Nevada National Security Site where the government carried out secret operations. The airfield at Area 51 is called Homey Airport, and the overall facility is often referred to as Groom Lake. Groom Lake is a salt flat, or dried-out lake, adjacent to the airport. </p>
<h2>The history</h2>
<p>In the early years of the <a href="https://kids.britannica.com/kids/article/Cold-War/352982">Cold War</a> between the United States and the Soviet Union, both nations sought new technological developments that might give one country more power than the other. A great amount of information about scientific achievements, such as on rockets or weapons – but also even on ways to grow more food or make fuel more efficient – was kept secret as an issue of national security. </p>
<p>A key part of not fighting another world war was, and still is, developing technologies to see what the other side is doing – that is, <a href="https://www.history.com/news/aerial-surveillance-spy-devices">surveillance technologies</a> that can spy on the enemy. The information gathered by new and improved surveillance technologies about new innovations with planes and weapons was very important to governments. </p>
<p>This meant that both the surveillance information and the technology to get it were closely held national security secrets. Very few people in the governments of the U.S. and Soviet Union knew about the secrets from the 1940s all the way up until the end of the Cold War in 1991. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A single-seat jet aircraft with no markings flies high above the clouds" src="https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536156/original/file-20230706-25-x0evon.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&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 U-2 spy plane was the first of many secrets kept at Area 51.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Usaf.u2.750pix.jpg">U.S. Air Force</a></span>
</figcaption>
</figure>
<p>Central to all this was the U.S.’s <a href="https://www.britannica.com/technology/U-2">U-2 spy plane</a>. It could fly higher than other airplanes and was made to travel over targets all around the world to take high-resolution photographs and measurements. Area 51 was selected in 1955 to test the U-2 in part because its remote location could help keep the plane secret. </p>
<p>Area 51 became the test site for other secret new aircraft. This included the <a href="https://airandspace.si.edu/collection-objects/lockheed-sr-71-blackbird/nasm_A19920072000">A-12</a>, which, like the U-2, was a fast-flying reconnaissance plane. The A-12 was first test flown at Homey Airport in 1962. It had a bulging disc-like center to carry additional fuel. Its shape and shiny titanium body could well have been responsible for some people’s reports about seeing spherical ships, also known as flying saucers. </p>
<p>Another important – and odd-shaped – aircraft first tested at Area 51 was the stealth fighter known as the <a href="https://www.britannica.com/technology/F-117">F-117</a>. It first flew at Homey Airport in 1981.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a single-seat odd-shaped jet aircraft flies high above the desert" src="https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536157/original/file-20230706-17-ckb57e.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"></a>
<figcaption>
<span class="caption">The F-117 stealth fighter looks like it could have come from another world but was made right here on Earth.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/File:F-117_Nighthawk_Front.jpg">U.S. Air Force</a></span>
</figcaption>
</figure>
<h2>Secrets and speculation</h2>
<p>“More Flying Objects Seen in Clark Sky,” read <a href="https://time.com/5627694/area-51-history/">the June 17, 1959, headline</a> in the Reno Evening Gazette newspaper. Reports like this of unidentified flying objects in the 1950s and 1960s fueled controversy and attention for Area 51. This was for three main reasons:</p>
<ol>
<li> Area 51 was highly secret and not publicly accessible. </li>
<li> The area was home to test flights of secret new airplanes that moved fast and in different ways than expected. </li>
<li> The Cold War was an era of political tension, and there were many movies and TV shows about space aliens at the time. </li>
</ol>
<p>When the government does not tell the public the full truth, no matter the reasons, secrets can <a href="https://www.atlasobscura.com/articles/manhattan-project-library-charlotte-serber-oppenheimer-fbi">lead to wild speculation</a>. Secrecy can leave room for conspiracy theories to develop. </p>
<p>Area 51 remains off-limits to civilian and regular military air traffic, a decade after the government acknowledged its existence. The 68 years of government secrecy has helped to <a href="https://theconversation.com/yes-im-searching-for-aliens-and-no-i-wont-be-going-to-area-51-to-look-for-them-120584">amplify suspicions, speculation and conspiracy theories</a>. These <a href="https://content.time.com/time/specials/packages/article/0,28804,1860871_1860876_1861006,00.html">conspiracy theories</a> include crashed alien spaceships, space aliens being experimented on, and even space aliens working at Area 51. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a small crane holds a disk-shaped object in front of a sign for a restaurant that includes an image of a space alien" src="https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536161/original/file-20230706-29-1fxni5.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"></a>
<figcaption>
<span class="caption">Speculation about space aliens at Area 51 has been part of popular culture for more than half a century.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/24874528@N04/14222448874/">Airwolfhound/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>There are much simpler explanations for what witnesses have seen near Area 51. After all, the public now knows about what was being tested at Area 51, and when. For example, as U-2 and A-12 flights increased in the 1950s and 1960s, <a href="https://www.nytimes.com/2021/06/24/us/politics/ufo-report-us-pentagon.html">so did local sightings of UFOs</a>. As balloons and planes crashed, and secret testing of new technologies as well as captured Soviet equipment continued, <a href="https://nsarchive.gwu.edu/briefing-book/intelligence/2013-10-29/area-51-file-secret-aircraft-soviet-migs">so did reports of UFO crashes and landings</a>. </p>
<p>In fact, many UFO sightings <a href="https://foreignpolicy.com/2013/08/15/declassified-the-cias-secret-history-of-area-51/">match almost exactly</a> with dates and times of flights of then-classified experimental aircraft. We also know that prototype drones and more recent versions <a href="https://www.washingtonpost.com/news/the-switch/wp/2013/08/16/the-cia-first-tested-drones-in-area-51-because-of-course-they-did/">have been tested at the site</a>.</p>
<p>In the end, there is no reason to think that anything other than earthly technologies have been behind the strange sights and sounds at Area 51.</p>
<p><em>This article has been updated to correct the descriptions of the name Area 51 and the U2 spy plane’s capabilities.</em></p>
<hr>
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<p class="fine-print"><em><span>Christopher Nichols does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>You’re not allowed to visit the part of Nevada known as Area 51. That’s because it’s a top-secret government facility. But the secrecy has to do with spy planes, not space aliens.Christopher Nichols, Professor of History, The Ohio State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2104352023-07-27T18:18:33Z2023-07-27T18:18:33ZWhistleblower calls for government transparency as Congress digs for the truth about UFOs<figure><img src="https://images.theconversation.com/files/539676/original/file-20230727-29-h44roy.jpg?ixlib=rb-1.1.0&rect=44%2C35%2C5845%2C3884&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A congressional subcommittee on unidentified anomalous phenomena met to hear testimony from military officers. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/the-u-s-capitol-building-royalty-free-image/1409850965?phrase=congress">Sarah Silbiger/Bloomberg via Getty Images</a></span></figcaption></figure><p>A <a href="https://oversight.house.gov/subcommittee/national-security/">congressional subcommittee</a> <a href="https://www.c-span.org/video/?529499-1/hearing-unidentified-anomalous-phenomena-uap">met on July 26, 2023, to hear testimony</a> from several military officers who allege the government is concealing evidence of UFOs. By holding a <a href="https://oversight.house.gov/hearing/unidentified-anomalous-phenomena-implications-on-national-security-public-safety-and-government-transparency/">hearing</a> on UFOs – <a href="https://www.latimes.com/politics/story/2023-07-24/congress-ufos-hearing-uap">now called</a> “unidentified anomalous phenomena” by government agencies – the subcommittee sought to understand whether these UAPs pose a threat to national security.</p>
<p>I’m an <a href="https://scholar.google.com/citations?user=OrRLRQ4AAAAJ&hl=en">astronomer</a> who studies and has written about <a href="https://wwnorton.com/books/9780393343861">cosmology</a>, <a href="https://wwnorton.com/books/9780393357509">black holes</a>, <a href="https://www.penguinrandomhouse.com/books/718149/worlds-without-end-by-chris-impey/">exoplanets</a> and <a href="https://www.cambridge.org/core/books/living-cosmos/11D69005D09D25581AE4E6684EC8A3C1">life in the universe</a>. I’m also on the <a href="http://meti.org/en/advisors">advisory council</a> for an international group that strategizes how to communicate with an extraterrestrial civilization should the need ever arise.</p>
<p>While the hearings brought attention to UAPs and could lead to more reporting from people who work in the military and aviation, the testimonies did not produce evidence to fundamentally change the understanding of UAPs.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A close-up shot of a blue striped suit and pink tie with a rectangular pin that has a UFO on it and the words 'I still want to believe'" src="https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539775/original/file-20230727-15-yzt55u.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">An audience member at the hearing wears an ‘X-Files’ UFO pin.</span>
<span class="attribution"><span class="source">AP Photo/Nathan Howard</span></span>
</figcaption>
</figure>
<h2>UFO oversight so far</h2>
<p>The House subcommittee hearing follows a flurry of activity over the past few years. Public interest in UAPs surged in 2017 after three Navy videos were leaked and <a href="https://www.nytimes.com/2017/12/16/us/politics/pentagon-program-ufo-harry-reid.html">The New York Times reported</a> on a shadowy UAP program run by the Pentagon. In <a href="https://theconversation.com/us-intelligence-report-on-ufos-no-aliens-but-government-transparency-and-desire-for-better-data-might-bring-science-to-the-ufo-world-163059">June 2021</a>, the Office of the Director of National Intelligence released a <a href="https://www.dni.gov/files/ODNI/documents/assessments/Prelimary-Assessment-UAP-20210625.pdf">report</a> on the phenomena. In November 2021, the Pentagon <a href="https://www.defense.gov/News/Releases/Release/Article/2853121/dod-announces-the-establishment-of-the-airborne-object-identification-and-manag/">formed a new group</a> to coordinate efforts to detect and identify objects in restricted airspace.</p>
<p>Then in May 2022, a House Intelligence subcommittee held the first congressional hearing in over half a century on military reports of UAPs. Little new light was shed on the true nature of the sightings, but the <a href="https://www.independent.co.uk/tech/ufo-senate-hearing-congress-live-pentagon-b2080711.html">officials tried to clarify the situation</a> by ruling things out.</p>
<p>While <a href="https://www.youtube.com/watch?v=FYfxwBQL69A&t=4s">officials noted</a> 18 occasions in which aerial objects had moved at considerable speed without visible means of propulsion, nobody had found unexplained wreckage or records of the military having either received communications from or having fired shots at UAPs. As such, the subcommittee decided that there was not yet enough evidence to claim UAPs are extraterrestrial.</p>
<p>Most recently, <a href="https://www.nasa.gov/feature/nasa-to-set-up-independent-study-on-unidentified-aerial-phenomena/">NASA convened</a> a panel in June 2022, which held its first public hearing in May this year. The panel will help NASA advise intelligence agencies and the Department of Defense on how to evaluate mysterious sightings. The panel is considering <a href="https://www.cnn.com/2023/05/31/world/nasa-uap-study-public-meeting-scn/index.html">800 sightings</a> accumulated over 27 years, with <a href="https://www.cnn.com/2023/05/31/world/nasa-uap-study-public-meeting-scn/index.html">50 to 100 new reports</a> coming in each month. Sean Kirkpatrick from the Department of Defense said that <a href="https://www.cnn.com/2023/05/31/world/nasa-uap-study-public-meeting-scn/index.html">only 2% to 5% of these are anomalous</a>, and the meeting drew no firm conclusions.</p>
<p>Which brings us to this week’s hearing. Congress is <a href="https://oversight.house.gov/release/national-security-subcommittee-to-hold-hearing-on-unidentified-anomalous-phenomena">getting frustrated</a> with the lack of transparency over UAP sightings. So the subcommittee is using its <a href="https://oversight.house.gov/about/">overall charge</a> of oversight and accountability to get some answers.</p>
<h2>Eyebrow-raising testimony</h2>
<p>Three witnesses, all ex-military officers, gave <a href="https://oversight.house.gov/hearing/unidentified-anomalous-phenomena-implications-on-national-security-public-safety-and-government-transparency/">sworn testimony</a> to the subcommittee. </p>
<p>David Fravor was a commander in the U.S. Navy in 2004, stationed on the USS Nimitz, when he and another pilot <a href="https://www.cbsnews.com/news/navy-ufo-sighting-60-minutes-2021-05-16/">saw an object behaving inexplicably</a>. Video of the encounter was released by the Department of Defense in 2017 and publicized by <a href="https://www.nytimes.com/2017/12/16/us/politics/unidentified-flying-object-navy.html">The New York Times</a>. </p>
<p><a href="https://oversight.house.gov/wp-content/uploads/2023/07/David-Fravor-Statement-for-House-Oversight-Committee.pdf">Fravor testified</a> that the technology he witnessed was far superior to anything human beings have. He described objects with no visible means of propulsion carrying out sudden maneuvers that no known technology could achieve.</p>
<p>“What concerns me is that there is no oversight from our elected officials on anything associated with our government possessing or working on craft that we believe are not of this world,” Fravor said. </p>
<p>The second witness, Ryan Graves, was an F-18 pilot for over a decade. While stationed at Virginia Beach in 2014, he says, UAP sightings were so frequent among his crew that they became part of daily briefs. <a href="https://oversight.house.gov/wp-content/uploads/2023/07/Ryan-HOC-Testimony.pdf">He recounted</a> a situation in which two jets had to take evasive action as they encountered a UAP. The description was striking – a dark gray cube inside a clear sphere – quite different from the classic “<a href="https://www.theguardian.com/lifeandstyle/2020/oct/13/is-the-flying-saucer-the-best-shape-for-a-spaceship">flying saucer</a>.”</p>
<p>Graves founded <a href="https://www.safeaerospace.org/">Americans for Safe Aerospace</a> to create a center of support and education for aircrew affected by UAP encounters. He testified that the group has 5,000 members and has taken information from 30 witnesses. Most are commercial pilots at major airlines. He alleged that all UAP videos since 2021 are classified by the Pentagon as secret or higher. Graves also said that only 5% of UAP sightings by military and commercial pilots are reported by the pilots that spot them. </p>
<p>“If everyone could see the sensor and video data that I have, there is no doubt that UAP would be a top priority for our defense, intelligence and scientific communities,” Graves said. </p>
<p>The real bombshell came from David Grusch, an Air Force intelligence officer who retired with the rank of major. His high level of security clearance meant he saw reports that were unknown to the public. He sought whistleblower protection after claiming that the U.S. government was <a href="https://thedebrief.org/intelligence-officials-say-u-s-has-retrieved-non-human-craft/">operating with secrecy</a> and above congressional oversight with regards to UAP – even claiming that crashed UAPs had yielded biological material of nonhuman origin. The <a href="https://abcnews.go.com/Politics/house-oversight-plans-ufo-hearing-after-unconfirmed-claims/story?id=99899883">Pentagon has denied</a> this claim. He also said he’d suffered retaliation after reporting this information to his superiors and to multiple inspectors general.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/0w5T2skzNI4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Grusch testifies that the U.S. government has recovered ‘nonhuman biologics.’</span></figcaption>
</figure>
<p>“I was informed, in the course of my official duties, of a multidecade UAP crash-retrieval and reverse-engineering program to which I was denied access,” Grusch said in <a href="https://oversight.house.gov/wp-content/uploads/2023/07/Dave_G_HOC_Speech_FINAL_For_Trans.pdf">his opening statement</a> to the subcommittee. The Pentagon has <a href="https://abcnews.go.com/Politics/house-oversight-plans-ufo-hearing-after-unconfirmed-claims/story?id=99899883">denied the existence of such a program</a> now or in the past. </p>
<h2>Calls for transparency</h2>
<p>While none of this testimony brought forward viable evidence of a broad government conspiracy, most UAP data is <a href="https://www.newsnationnow.com/space/ufo/pentagon-blocks-lawmakers-ufo-data-uap-hearing/">not made public</a> and is held by intelligence agencies or the Pentagon. Lawmakers from both parties called for more government transparency. When questioned, all three witnesses said that UAPs represented a clear threat to national security. </p>
<p>If these testimonies are truthful, UAPs of advanced technology – whether they originate from a foreign adversary or not – that make routine incursions into U.S. airspace are a cause for concern.</p>
<p>For now, the subcommittee will continue its work. A tangible outcome will probably be an <a href="https://oversight.house.gov/whistle/">anonymous reporting mechanism</a> to overcome the stigma commercial and military pilots feel when they witness a UAP. The push for government transparency will likely intensify, and subcommittee members hope to have a classified briefing to evaluate the claims made by Grusch.</p>
<p>As a scientist, I’m trained to be skeptical, and I know that <a href="http://www.ianridpath.com/ufo/astroufo1.html">most UFO sightings</a> <a href="https://theconversation.com/why-people-tend-to-believe-ufos-are-extraterrestrial-208403">have mundane explanations</a>. Visual evidence is also notoriously difficult to interpret, and even the dramatic Navy videos have been <a href="https://www.leonarddavid.com/debunking-navy-ufo-videos/">debunked</a>. More and better data will help resolve the issue, but the gold standard is physical evidence. If Grusch’s claims of crashed UAPs are ever verified, that will be the first UAP hearing with a truly dramatic outcome.</p>
<p><em>This article was updated on August 2, 2023 to correct the date of the Congressional hearing.</em></p><img src="https://counter.theconversation.com/content/210435/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>All who testified before a congressional subcommittee claimed that UFOs pose a threat to national security, though there’s still no public evidence that UFOs are extraterrestrial.Chris Impey, University Distinguished Professor of Astronomy, University of ArizonaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2077932023-07-19T12:23:49Z2023-07-19T12:23:49ZFirst contact with aliens could end in colonization and genocide if we don’t learn from history<figure><img src="https://images.theconversation.com/files/536178/original/file-20230706-15-uc6ukv.jpg?ixlib=rb-1.1.0&rect=44%2C0%2C4928%2C3260&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">SETI has been listening for markers that may indicate alien life -- but is doing so ethical?</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/4TpL_oVkUcQ">Donald Giannati via Unsplash</a></span></figcaption></figure><p>We’re only halfway through 2023, and it feels already like the year of alien contact. </p>
<p>In February, President Joe Biden <a href="https://www.whitehouse.gov/briefing-room/speeches-remarks/2023/02/16/remarks-by-president-biden-on-the-united-states-response-to-recent-aerial-objects/">gave orders</a> to shoot down three unidentified aerial phenomena – NASA’s title for UFOs. Then, the alleged <a href="https://www.cnn.com/videos/business/2021/05/19/ufo-navy-video-jeremy-corbell-orig-jm.cnn">leaked footage</a> from a Navy pilot of a UFO, and then news of a <a href="https://www.theguardian.com/world/2023/jun/06/whistleblower-ufo-alien-tech-spacecraft">whistleblower’s report</a> on a possible U.S. government cover-up about UFO research. Most recently, an independent analysis <a href="https://douglasjohnson.ghost.io/senate-intelligence-bill-gives-holders-of-non-earth-origin-six-months/">published in June</a> suggests that UFOs might have been collected by a clandestine agency of the U.S. government.</p>
<p>If any actual evidence of extraterrestrial life emerges, whether from whistleblower testimony or an admission of a cover-up, humans would face a historic paradigm shift. </p>
<p>As members of an Indigenous studies working group who were asked to lend our disciplinary expertise to a workshop affiliated with the <a href="https://seti.berkeley.edu/">Berkeley SETI Research Center</a>, we have studied centuries of culture contacts and their outcomes from around the globe. Our collaborative preparations for the workshop drew from transdisciplinary research in Australia, New Zealand, Africa and across the Americas. </p>
<p>In its final form, our <a href="https://escholarship.org/uc/item/2sq6f3b0">group statement</a> illustrated the need for diverse perspectives on the ethics of listening for alien life and a broadening of <a href="https://doi.org/10.17953/aicrj.45.1.shorter">what defines “intelligence” and “life.”</a> Based on our findings, we consider first contact less as an event and more as a long process that has already begun. </p>
<h2>Who’s in charge of first contact</h2>
<p>The question of who is “in charge” of preparing for contact with alien life immediately comes to mind. The communities – and their interpretive lenses – most likely to engage in any contact scenario would be military, corporate and scientific. </p>
<p>By giving Americans the legal right to profit from space tourism and planetary resource extraction, the <a href="https://www.govinfo.gov/app/details/COMPS-15975">Commercial Space Launch Competitiveness Act of 2015</a> could mean that corporations will be the first to find signs of extraterrestrial societies. Otherwise, while detecting unidentified aerial phenomena is usually a military matter, and NASA takes the lead on <a href="https://theconversation.com/blasting-out-earths-location-with-the-hope-of-reaching-aliens-is-a-controversial-idea-two-teams-of-scientists-are-doing-it-anyway-182036">sending messages from Earth</a>, most activities around extraterrestrial communications and evidence fall to a program called <a href="https://www.seti.org/">SETI, or the search for extraterrestrial intelligence</a>. </p>
<p>SETI is a collection of scientists with a <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/project-seti">variety of research endeavors</a>, including Breakthrough Listen, which listens for “<a href="https://iopscience.iop.org/article/10.3847/1538-3881/abf649">technosignatures</a>,” or markers, like pollutants, <a href="https://theconversation.com/signatures-of-alien-technology-could-be-how-humanity-first-finds-extraterrestrial-life-191054">of a designed technology</a>. </p>
<p>SETI investigators are <a href="https://www.seti.org/become-pi-or-affiliate">virtually always STEM</a> – science, technology, engineering and math – scholars. Few in the social science and humanities fields have been afforded opportunities to contribute to concepts of and preparations for contact.</p>
<p>In a promising act of disciplinary inclusion, the <a href="https://seti.berkeley.edu/listen/">Berkeley SETI Research Center</a> in 2018 invited working groups – including our <a href="https://doi.org/10.17953/aicrj.45.1.atalay_etal">Indigenous studies working group</a> – from outside STEM fields to craft perspective papers for SETI scientists to consider.</p>
<h2>Ethics of listening</h2>
<p>Neither Breakthough Listen nor SETI’s site features a current <a href="https://doi.org/10.1002/9781119711186.ch13">statement of ethics</a> beyond a <a href="https://doi.org/10.1098/rsta.2010.0311">commitment to transparency</a>. Our working group was <a href="https://bis-space.com/shop/product/do-no-harm-cultural-imperialism-and-the-ethics-of-active-seti/">not the first</a> to raise this issue. And while the <a href="https://www.seti.org/event/seti-live-ethics-outer-space">SETI Institute</a> and <a href="https://www.pseti.psu.edu/seminar/">certain research centers</a> have included ethics in their event programming, it seems relevant to ask who NASA and SETI answer to, and what ethical guidelines they’re following for a potential first contact scenario. </p>
<p><a href="https://seti.wp.st-andrews.ac.uk/">SETI’s Post-Detection Hub</a> – another rare exception to SETI’s STEM-centrism – seems the most likely to develop a range of contact scenarios. The possible circumstances imagined include finding ET artifacts, detecting signals from thousands of light years away, dealing with linguistic incompatibility, finding microbial organisms in space or on other planets, and biological contamination of either their or our species. Whether the U.S. government or heads of military would heed these scenarios is another matter. </p>
<p>SETI-affiliated scholars <a href="https://youtu.be/1Op7AN0MeNw?t=1237">tend to reassure critics</a> that the intentions of those listening for technosignatures are benevolent, since “what harm could come from simply listening?” The chair emeritus of SETI Research, Jill Tarter, <a href="https://www.jstor.org/stable/j.ctt1814k0q">defended listening</a> because any ET civilization would perceive our listening techniques as immature or elementary. </p>
<p>But our working group drew upon the history of colonial contacts <a href="https://doi.org/10.17953/aicrj.45.1.shorter">to show the dangers</a> of thinking that whole civilizations are comparatively advanced or intelligent. For example, when Christopher Columbus and other European explorers came to the Americas, those relationships were shaped by <a href="https://doi.org/10.1163/9789004421882_011">the preconceived notion</a> that the “Indians” were less advanced due to <a href="https://www.nebraskapress.unl.edu/nebraska-paperback/9780803253445/">their lack of writing</a>. This led to decades of <a href="https://www.harpercollins.com/products/the-other-slavery-andres-resendez?variant=39936147849250">Indigenous servitude</a> in the Americas. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black and white engraving of a group of armed and armored men standing on the shore speaking to many naked men. Large ships sail in the background." src="https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/537513/original/file-20230714-23-b71osm.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&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 16th century engraving shows Christopher Columbus landing in the Americas, where he and his explorers deemed the Indigenous people there as ‘primitive,’ as they had no writing system.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Columbus_landing_on_Hispaniola.JPG">Theodor de Bry/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>The working group statement also suggested that the act of listening is itself already within a “<a href="https://doi.org/10.1177/2514848619862191">phase of contact</a>.” Like colonialism itself, contact might best be thought of as a series of events that starts with planning, rather than a singular event. Seen this way, isn’t listening potentially without permission just another form of surveillance? To listen intently but indiscriminately seemed to our working group like a <a href="https://doi.org/10.17953/aicrj.45.1.shorter_tallbear">type of eavesdropping</a>. </p>
<p>It seems contradictory that we begin our relations with aliens by listening in without their permission while actively working to stop other countries from <a href="https://www.youtube.com/watch?v=QI_rUsLT5Iw&ab_channel=WION">listening to certain U.S. communications</a>. If humans are initially perceived as disrespectful or careless, ET contact could more likely lead to <a href="https://theconversation.com/how-could-we-build-an-invisibility-cloak-to-hide-earth-from-an-alien-civilization-57092">their colonization of us</a>.</p>
<h2>Histories of contact</h2>
<p>Throughout histories of Western colonization, even in those few cases when contactees were intended to be protected, contact has led to brutal violence, pandemics, enslavement and genocide. </p>
<p>James Cook’s 1768 voyage on the HMS Endeavor was initiated by the <a href="https://doi.org/10.1098/rsnr.1969.0003">Royal Society</a>. This prestigious British academic society charged him with calculating the solar distance between the Earth and the Sun by measuring the visible movement of Venus across the Sun from Tahiti. The society strictly forbade him from any colonial engagements. </p>
<p>Though he achieved his scientific goals, Cook also <a href="https://doi.org/10.1017/S1743921305001262">received orders</a> from the Crown to map and claim as much territory as possible on the return voyage. Cook’s actions put into motion wide-scale colonization and Indigenous dispossession across Oceania, including the <a href="https://doi.org/10.17953/aicrj.45.1.lempert">violent conquests of Australia and New Zealand</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A painting showing five men, two dogs, and a statue of a woman standing in a clearing near the ocean shore. The center man, James Cook, is holding his hat out." src="https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=431&fit=crop&dpr=1 600w, https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=431&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=431&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=542&fit=crop&dpr=1 754w, https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=542&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/537303/original/file-20230713-17-55wdsd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=542&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 1768 voyage of British captain James Cook, center, put into motion wide-scale colonization and Indigenous dispossession across Oceania.</span>
<span class="attribution"><a class="source" href="https://nla.gov.au/nla.obj-135646842/view">John Hamilton Mortimer via the National Library of Australia</a></span>
</figcaption>
</figure>
<p>The Royal Society gave Cook a “<a href="https://bigthink.com/thinking/star-trek-prime-directive/">prime directive</a>” of doing no harm and to only conduct research that would broadly benefit humanity. However, explorers are rarely independent from their funders, and their explorations reflect the political contexts of their time. </p>
<p>As scholars attuned to both research ethics and histories of colonialism, we wrote about Cook in our working group statement to showcase why SETI might want to explicitly disentangle their intentions <a href="https://www.govinfo.gov/app/details/COMPS-15975">from those of corporations, the military and the government</a>. </p>
<p>Although separated by vast time and space, both Cook’s voyage and SETI share key qualities, including their appeal to celestial science in the service of all humanity. They also share a mismatch between their ethical protocols and the likely long-term impacts of their success.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/5gZwLGrJQrM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This BBC video describes the modern ramifications of Captain James Cook’s colonial legacy in New Zealand.</span></figcaption>
</figure>
<p>The initial domino of a public ET message, or recovered bodies or ships, could initiate <a href="https://doi.org/10.1098/rsta.2010.0236">cascading events</a>, including military actions, corporate resource mining and perhaps even geopolitical reorganizing. The history of imperialism and colonialism on Earth illustrates that <a href="https://doi.org/10.1080/14623520601056240">not everyone benefits from colonization</a>. No one can know for sure <a href="https://theconversation.com/is-your-religion-ready-to-meet-et-32541">how engagement with extraterrestrials would go</a>, though it’s better to consider cautionary tales from Earth’s own history sooner rather than later.</p>
<p><em>This article has been updated to correct the date of James Cook’s voyage.</em></p><img src="https://counter.theconversation.com/content/207793/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Delgado Shorter has received funding from the National Science Foundation, the University of California, and the California Community Foundation. </span></em></p><p class="fine-print"><em><span>William Lempert has received funding from Bowdoin College, the Wenner-Gren Foundation for Anthropological Research, the Fulbright IIE US Scholar Program, the Lois Roth Endowment, the Andrew W. Mellon Foundation, and the American Council of Learned Societies.</span></em></p><p class="fine-print"><em><span>Kim TallBear does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Three Indigenous studies scholars draw from colonial histories and explain why listening for alien life can have ethical ramifications.David Delgado Shorter, Professor of World Arts and Cultures/Dance, University of California, Los AngelesKim TallBear, Professor of Native Studies, University of AlbertaWilliam Lempert, Assistant Professor of Anthropology, Bowdoin CollegeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2084032023-07-17T12:26:25Z2023-07-17T12:26:25ZWhy people tend to believe UFOs are extraterrestrial<figure><img src="https://images.theconversation.com/files/536674/original/file-20230710-27-qxl8co.jpg?ixlib=rb-1.1.0&rect=63%2C0%2C7071%2C4657&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Photos claiming to be UFO evidence are often doctored or otherwise ambiguous. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/in-flight-above-urban-park-royalty-free-image/BD0513-001?phrase=ufos&adppopup=true">Ray Massey/The Image Bank via Getty Images</a></span></figcaption></figure><p>Most of us still call them UFOs – unidentified flying objects. NASA <a href="https://www.nasa.gov/feature/nasa-announces-unidentified-aerial-phenomena-study-team-members/">recently adopted</a> the term “unidentified anomalous phenomena,” or UAP. Either way, every few years popular claims resurface that these things are not of our world, or that the <a href="https://thedebrief.org/intelligence-officials-say-u-s-has-retrieved-non-human-craft/">U.S. government has some stored away</a>.</p>
<p>I’m <a href="https://scholar.google.com/citations?user=ZEQu09wAAAAJ&hl=en">a sociologist</a> who focuses on the interplay between individuals and groups, especially concerning shared beliefs and misconceptions. As for why UFOs and their alleged occupants enthrall the public, I’ve found that normal human perceptual and social processes explain UFO buzz as much as anything up in the sky. </p>
<h2>Historical context</h2>
<p>Like political scandals and high-waisted jeans, UFOs trend in and out of collective awareness but never fully disappear. <a href="https://abcnews.go.com/Technology/ufos-exist-americans-national-geographic-survey/story?id=16661311">Thirty years of polling</a> find that <a href="https://www.pewresearch.org/short-reads/2021/06/30/most-americans-believe-in-intelligent-life-beyond-earth-few-see-ufos-as-a-major-national-security-threat/">25%-50% of surveyed Americans</a> believe at least some UFOs are alien spacecraft. Today in the U.S., over <a href="https://news.gallup.com/poll/353420/larger-minority-says-ufos-alien-spacecraft.aspx">100 million adults</a> think our galactic neighbors pay us visits.</p>
<p>It wasn’t always so. Linking objects in the sky with visiting extraterrestrials has risen in popularity only in the <a href="https://theconversation.com/from-flying-boats-to-secret-soviet-weapons-to-alien-visitors-a-brief-cultural-history-of-ufos-164128">past 75 years</a>. Some of this is probably market-driven. Early UFO stories boosted newspaper and magazine sales, and today they are reliable <a href="https://kipac.stanford.edu/highlights/aliens-could-be-out-there-dont-trust-clickbait">clickbait</a> online. </p>
<p>In 1980, a popular book called “<a href="https://archive.org/details/roswellincident00berl">The Roswell Incident</a>” by Charles Berlitz and William L. Moore described an alleged flying saucer crash and government cover-up 33 years prior near Roswell, New Mexico. The only evidence ever to emerge from this story was a small string of downed weather balloons. Nevertheless, the book coincided with a <a href="https://www.washingtonpost.com/history/2022/07/08/roswell-flying-saucer-ufo/">resurgence of interest</a> in UFOs. From there, a steady stream of UFO-themed <a href="https://tvshowpilot.com/fun-posts/best-alien-tv-shows/">TV shows</a>, <a href="https://www.imdb.com/list/ls041828914/">films</a>, and <a href="https://screenrant.com/netflix-ufo-documentaries-best-greatest/">pseudo-documentaries</a> has fueled public interest. Perhaps inevitably, <a href="https://www.press.jhu.edu/books/title/12893/conspiracy">conspiracy theories</a> about government cover-ups have risen in parallel.</p>
<p>Some UFO cases inevitably remain unresolved. But despite <a href="https://theconversation.com/why-is-the-pentagon-interested-in-ufos-116714">the growing interest</a>, multiple <a href="https://www.af.mil/The-Roswell-Report/">investigations</a> have found <a href="https://www.washingtonpost.com/magazine/2021/08/11/stop-ufo-mania-no-evidence-of-aliens/">no evidence</a> that UFOs are of extraterrestrial origin – other than the occasional meteor or misidentification of <a href="https://www.nasa.gov/vision/universe/watchtheskies/03may_maximumvenus.html">Venus</a>. </p>
<p>But the U.S. Navy’s 2017 <a href="https://www.nytimes.com/2017/12/16/us/politics/pentagon-program-ufo-harry-reid.html">Gimbal video</a> continues to appear in the media. It shows strange <a href="https://www.youtube.com/watch?v=2TumprpOwHY&ab_channel=ABCNews">objects filmed by fighter jets</a>, often interpreted as evidence of alien spacecraft. And in June 2023, an otherwise credible Air Force veteran and former intelligence officer made the <a href="https://thedebrief.org/intelligence-officials-say-u-s-has-retrieved-non-human-craft/">stunning claim</a> that the U.S. government is storing numerous downed alien spacecraft and their dead occupants. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/2TumprpOwHY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">UFO videos released by the U.S. Navy, often taken as evidence of alien spaceships.</span></figcaption>
</figure>
<h2>Human factors contributing to UFO beliefs</h2>
<p>Only a small percentage of UFO believers are <a href="https://news.gallup.com/vault/190592/gallup-vault-eyewitnesses-flying-saucers.aspx">eyewitnesses</a>. The rest base their opinions on eerie images and videos strewn across both social media and traditional mass media. There are astronomical and biological reasons to be <a href="https://www.bloomsbury.com/us/skeptic-encyclopedia-of-pseudoscience-2-volumes-9781576076538/">skeptical</a> of UFO claims. But less often discussed are the psychological and social factors that bring them to the popular forefront.</p>
<p>Many people would love to know whether or not <a href="https://exoplanets.nasa.gov/news/1675/life-in-the-universe-what-are-the-odds/">we’re alone in the universe</a>. But so far, the evidence on UFO origins is ambiguous at best. Being <a href="https://thedecisionlab.com/biases/ambiguity-effect">averse to ambiguity</a>, people want answers. However, being highly motivated to find those answers can <a href="https://doi.org/10.1037/0033-2909.108.3.480">bias judgments</a>. People are more likely to accept weak evidence or fall prey to optical illusions if they support preexisting beliefs. </p>
<p>For example, in the 2017 Navy video, the UFO appears as a cylindrical aircraft moving rapidly over the background, rotating and darting in a manner unlike any terrestrial machine. <a href="https://www.skeptic.com/reading_room/gimbal-video-genuine-ufo-or-camera-artifact/">Science writer Mick West’s analysis</a> challenged this interpretation using data displayed on the tracking screen and some basic geometry. He explained how the movements attributed to the blurry UFO are an illusion. They stem from the plane’s trajectory relative to the object, the quick adjustments of the belly-mounted camera, and misperceptions based on our tendency to assume cameras and backgrounds are stationary.</p>
<p>West found the UFO’s flight characteristics were more like a bird’s or <a href="https://amuedge.com/beyond-ufos-what-are-navy-pilots-seeing-in-the-skies/">a weather balloon’s</a> than an acrobatic interstellar spacecraft. But the illusion is compelling, especially with the Navy’s still deeming the object unidentified.</p>
<p><a href="https://www.youtube.com/watch?v=AvhMMhW-JN0&t=249s&ab_channel=MickWest">West also addressed</a> the former intelligence officer’s <a href="https://thedebrief.org/intelligence-officials-say-u-s-has-retrieved-non-human-craft/">claim that the U.S. government possesses crashed UFOs</a> and dead aliens. He emphasized caution, given the whistleblower’s only evidence was that people he trusted told him they’d seen the alien artifacts. West noted we’ve <a href="https://bigthink.com/13-8/military-whistleblowers-ufos-70-years/">heard this sort of thing before</a>, along with promises that the proof will soon be revealed. But it never comes.</p>
<p>Anyone, including pilots and intelligence officers, can be socially influenced to see things that aren’t there. Research shows that hearing from others who claim to have seen something extraordinary is enough to <a href="https://www.jstor.org/stable/10.1525/sop.2001.44.1.21">induce similar judgments</a>. The effect is heightened when the influencers are numerous or higher in status. Even recognized experts aren’t immune from <a href="https://www.bbc.com/news/av/world-us-canada-65771398">misjudging unfamiliar images</a> obtained under unusual conditions.</p>
<h2>Group factors contributing to UFO beliefs</h2>
<p>“Pics or it didn’t happen” is a <a href="https://www.theguardian.com/news/2015/feb/26/pics-or-it-didnt-happen-mantra-instagram-era-facebook-twitter">popular expression</a> on social media. True to form, users are posting countless shaky images and videos of UFOs. Usually they’re nondescript lights in the sky captured on cellphone cameras. But they can <a href="https://www.feedough.com/why-things-go-viral/">go viral on social media</a> and reach millions of users. With no higher authority or organization propelling the content, social scientists call this a bottom-up <a href="https://doi.org/10.1146/annurev.soc.24.1.265">social diffusion</a> process.</p>
<p>In contrast, top-down diffusion occurs when information emanates from centralized agents or organizations. In the case of UFOs, sources have included social institutions like <a href="https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104590/unidentified-flying-objects-and-air-force-project-blue-book/">the military</a>, individuals with large public platforms like <a href="https://thehill.com/homenews/4062715-us-has-downplayed-the-number-of-ufo-sightings-senator-hawley/">U.S. senators</a>, and major media outlets like <a href="https://www.cbsnews.com/news/ufo-military-intelligence-60-minutes-2021-08-29/">CBS</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two circle-and-line graphics, the left showing several circles connected to one another with lines, while the right shows one circle at the top connecting several other circles" src="https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=284&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=284&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=284&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=357&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=357&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536695/original/file-20230710-15-14kf6i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=357&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 left image shows bottom-up diffusion, in which information spreads from person to person. The right shows top-down, in which information spreads from one authority.</span>
<span class="attribution"><span class="source">Barry Markovsky</span></span>
</figcaption>
</figure>
<p>Amateur organizations also promote active personal involvement for many thousands of members, <a href="https://mufon.com/">the Mutual UFO Network</a> being among the oldest and largest. But as Sharon A. Hill points out in her book “<a href="https://mcfarlandbooks.com/product/scientifical-americans/">Scientifical Americans</a>,” these groups apply questionable standards, spread misinformation and garner little respect within mainstream scientific communities.</p>
<p>Top-down and bottom-up <a href="https://doi.org/10.31269/triplec.v3i2.21">diffusion processes</a> can combine into <a href="https://qz.com/1714598/information-feedback-loops-make-social-media-more-dangerous">self-reinforcing loops</a>. Mass media spreads UFO content and piques worldwide interest in UFOs. More people aim their cameras at the skies, creating more opportunities to capture and share odd-looking content. Poorly documented UFO pics and videos spread on social media, <a href="https://www.cbc.ca/radio/asithappens/as-it-happens-the-monday-edition-1.6065136/why-this-ufo-video-analyst-doesn-t-buy-the-hype-around-the-pentagon-report-1.6065138">leading media outlets</a> to grab and republish the most intriguing. Whistleblowers emerge periodically, fanning the flames with claims of secret evidence.</p>
<p>Despite the hoopla, nothing ever comes of it.</p>
<p>For a <a href="https://theconversation.com/are-we-alone-the-question-is-worthy-of-serious-scientific-study-98843">scientist familiar with the issues</a>, skepticism that UFOs carry alien beings is wholly separate from the <a href="https://www.space.com/25219-drake-equation.html">prospect of intelligent life</a> elsewhere in the universe. Scientists engaged in the <a href="https://www.seti.org/">search for extraterrestrial intelligence</a> have a number of ongoing research projects designed to detect signs of extraterrestrial life. If intelligent life is out there, they’ll likely be the first to know. </p>
<p>As astronomer <a href="https://www.simonandschuster.com/books/Contact/Carl-Sagan/9781501197987">Carl Sagan wrote</a>, “The universe is a pretty big place. If it’s just us, seems like an awful waste of space.”</p><img src="https://counter.theconversation.com/content/208403/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Barry Markovsky does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>While UFO videos might seem compelling, they’re rarely backed up with evidence. A sociologist explains why claims of alien life gain traction through both social and mass media every few years.Barry Markovsky, Distinguished Professor Emeritus of Sociology, University of South CarolinaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2045672023-05-23T11:14:46Z2023-05-23T11:14:46ZHow Alien mutated from a sci-fi horror film into a multimedia universe<p>A new life form was born on May 25 1979 when an alien exploded from the chest of a bewildered officer aboard the commercial towing vessel, Nostromo. The alien that comes to be known as the xenomorph escapes, grows, stalks and kills all but one of the ship’s crew. The lone human survivor, Ellen Ripley, played by Sigourney Weaver, blasts it into deep space turning it and her into icons. </p>
<p>We are, of course, talking about the cinematic classic, Alien.</p>
<p>But what was born that day was not just a horrifying monster. It would become a fully fledged fictional world that, in the four decades following, has become an indelible part of our popular culture. And it is a topic we explore in our new book, <a href="https://global.oup.com/academic/product/alien-legacies-9780197556030?cc=gb&lang=en&">Alien Legacies</a>.</p>
<p>Though initially conceived as a cash-in on the popularity of science fiction in the aftermath of Star Wars, Alien grew from a hugely successful film into not only a franchise but a whole universe. It spawned three sequels - James Cameron’s Aliens (1986), David Fincher’s Alien3 (1992) and Jean-Pierre Jeunet’s Alien Resurrection (1997). </p>
<p>There were also two prequels - Prometheus (2012) and Alien Covenant (2017), which were both directed by Scott. And finally, there was a spin-off “mashup” franchise - Alien vs Predator directed by Paul WS Anderson (2004), and its sequel Requiem (2007). </p>
<p>It has inspired innovation and creativity beyond the films. There have been novelisations, video games, audiobooks, comics and <a href="https://www.semanticscholar.org/paper/%E2%80%98Ages-five-and-up%E2%80%99%3A-Alien-toys-for-children-and-the-Antunes-Plowman/37a5b6f9d25db0aa08a24322bd82cbcd7bd87d87">toys</a>.</p>
<p>The first two films, Alien and Aliens, have enjoyed considerable scrutiny given their cultural presence and resonance for debates concerning gender, technology and genetics. </p>
<p>But what has received less focus is what Alien has become. The franchise has proliferated and mutated across various forms of media while staying true to its cinematic origins.</p>
<p>Alien, like Star Wars, is what we can now call a “transmedia franchise”. It has pioneered ways of expanding storytelling across media boundaries. Our book examines the transmedia universe as a whole, addressing the original films, the prequels and everything that followed. </p>
<p>The franchise has been open to adopting new methods and ideas, as well as adapting to changes in new media technology and politics. </p>
<p>In fact, one almost entirely neglected aspect of the Alien universe we explore are documents purporting to be “real” crew profiles, training manuals and diaries that expand upon and develop our knowledge and understanding of this fictional world. </p>
<p>One of the extras on the 2010 Alien Anthology Blu-ray collection was a special feature called Weyland-Yutani Inquest: Nostromo Dossiers. This was a collection of corporate documents detailing the professional lives of the Nostromo spaceship crew.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/I0yDagVBGug?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">From The Weyland-Yutani Report: A look at the Nostromo’s crew including past employment and personal life details.</span></figcaption>
</figure>
<p>Some of this material, such as the <a href="https://avp.fandom.com/wiki/Aliens:_Colonial_Marines_Technical_Manual">Colonial Marines Technical Manual</a>, has been created by fans. It found its way into gaming instalments of the franchise having been picked up and explored by the many creative artists and writers who have worked in the Alien universe. These include Aliens versus Predator, Aliens versus Predator: Extinction and Aliens: Colonial Marines (2013).</p>
<p>The attempt by media companies to control and manage fan practice is not new, but it demands our attention. <a href="https://ew.com/movies/2019/03/13/alien-trailer-shorts-40th-anniversary/">Inviting people</a> to pitch their own short films set in the Alien universe to mark the fortieth anniversary in 2019 was a canny means by 20th Century Fox to curry favour with the fans of the series. </p>
<p>Similarly, transmedia marketing campaigns have grown to include fictional evil corporate websites, exclusive events at conventions, personalised advertising and franchise universe websites. </p>
<p>We argue that Alien’s transmedia marketing is <a href="https://www.forbes.com/sites/dorothypomerantz/2012/04/18/prometheus-when-movie-marketing-goes-very-right/">particularly captivating</a> because it is closely linked to the film’s production. As a result, these marketing campaigns are arguably becoming as creative and entertaining as the films themselves. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/XqW4JgI4-Vw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The transmedia marketing campaign for the Prometheus film.</span></figcaption>
</figure>
<p>The Alien series asks existential questions uncommon in mainstream blockbuster cinema about the origins and destiny of humanity and the dividing line between the human and the machine. </p>
<p>Alien should not be seen, as popular culture so often is, as unimportant or irrelevant to our understanding of ourselves as a species. It has the potential to contribute to our knowledge and enlightenment. </p>
<p>The continuing debate among scholars and fans surrounding the Alien franchise demonstrates how popular culture can bridge disciplinary boundaries and make complex academic debates more accessible. It helps us better understand the significant questions we must ponder as humans. </p>
<p>We hope our book will contribute to conversations about Alien. It explores its relevance to contemporary debates and paves the way for future studies on the franchise. After all, it has entered an uncertain <a href="https://www.semanticscholar.org/paper/World-building%2C-Retconning-and-Legacy-Rebooting%3A-Fleury/01dd0b7bc45907cf1f56e55e1237c6d3678609af">new phase</a> under the control of a new owner. </p>
<p>In 2019, Disney bought Fox and with it the rights to Alien. And Disney is a company that, throughout its history, has shown itself willing and able to adapt and build upon all aspects of its holdings in a variety of ways. </p>
<p>This starts with <a href="https://www.ign.com/articles/new-alien-movie-set-to-begin-production-this-month-as-cast-and-synopsis-is-revealed">Fede Alvarez’s untitled Alien film</a>, currently in production, and set for release via Disney’s Hulu streaming service. </p>
<p>Fans and academics will both probably continue to chase Ripley and the xenomorphs across the cosmos for the next forty years.</p><img src="https://counter.theconversation.com/content/204567/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathan Abrams has received and continues to receive funding from charitable organisations and research councils.</span></em></p><p class="fine-print"><em><span>Gregory Frame has in the past received funding from disciplinary subject associations and research councils.</span></em></p>A new book explores the enormous Alien franchise spawned by the 1979 film.Nathan Abrams, Professor of Film Studies, Bangor UniversityGregory Frame, Teaching Associate in Film and Television Studies, University of NottinghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2023522023-05-18T20:01:51Z2023-05-18T20:01:51Z‘Habits of civilised life’: how one state forced Indigenous people to meet onerous conditions to obtain citizenship<p><em>Note of warning: This article refers to deceased Aboriginal people, their words, names and images. Words attributed to them and images in the article are already in the public domain. Also, historical language is used in this article that may cause offence. Individuals and communities should be warned that they may read or see things in this article that could cause distress.</em></p>
<hr>
<p>In the breakthrough High Court case <a href="https://www.hcourt.gov.au/cases/case_b43-2018">Love and Thoms vs Commonwealth</a> in 2020, the court ruled that First Nations people could not be considered aliens in Australia. As Justice James Edelman noted in the decision,</p>
<blockquote>
<p>whatever the other manners in which they were treated […] Aboriginal people were not ‘considered as foreigners in a kingdom which is their own’.</p>
</blockquote>
<p>Yet, in my upcoming book with historian Kate Bagnall, I look at how Aboriginal and Torres Strait Islander people were long denied the rights of citizenship in their own land due to discriminatory laws – perhaps no more so than in Western Australia.</p>
<p>Until the 1970s, Western Australia still forced Aboriginal people to “dissolve tribal and native associations” and “adopt the manner and habits of civilised life” for two years before they could apply for citizenship under the state’s <a href="https://aiatsis.gov.au/sites/default/files/docs/digitised_collections/remove/52766.pdf">Natives (Citizenship Rights) Act 1944</a></p>
<p>Western Australia had <a href="https://www.amazon.com/Birthright-Citizens-History-Antebellum-America/dp/1316604721?asin=1316604721&revisionId=&format=4&depth=1.">copied</a> racially discriminatory provisions on citizenship from the United States, specifically the outdated 1918 US Federal Code, with strong echoes of the notorious “<a href="https://www.theatlantic.com/ideas/archive/2018/10/birthright-citizenship-was-won-freed-slaves/574498/">Black Laws</a>” from the early 1800s.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/526732/original/file-20230517-17-luw1sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526732/original/file-20230517-17-luw1sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=957&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526732/original/file-20230517-17-luw1sy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=957&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526732/original/file-20230517-17-luw1sy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=957&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526732/original/file-20230517-17-luw1sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1202&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526732/original/file-20230517-17-luw1sy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1202&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526732/original/file-20230517-17-luw1sy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1202&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A letter from a WA government official to the US consul in Perth in 1943, seeking input on US government citizenship policies.</span>
<span class="attribution"><span class="source">State Records Office of Western Australia</span></span>
</figcaption>
</figure>
<p>As Garth Nettheim and Larissa Behrendt note in the 2010 edition of Laws of Australia, the Western Australian law “throughout its life was inconsistent with the Commonwealth legislation” and therefore unlawful. </p>
<p>This is because, from the time of federation, nationality and citizenship were matters for federal, not state law. </p>
<p>Under British law that had remained <a href="http://classic.austlii.edu.au/au/journals/AJLH/2004/8.html">unchanged since the 17th century</a>, all Aboriginal Australians were already considered British subjects under colonial rule. And in 1948, the Nationality and Citizenship Act gave citizenship to all Australians previously deemed British subjects, including Aboriginal people.</p>
<p>Noongar activists knew they were already citizens under the laws imposed by white settlers and called for the rights and protections that should have been granted to them. </p>
<p>As <a href="https://adb.anu.edu.au/biography/abdullah-george-cyril-12117">George Abdullah</a>, founder of the Aboriginal Advancement Council of WA and president of the Aboriginal Rights Council, said in 1962: </p>
<blockquote>
<p>Full Australian citizenship was the natives’ birthright, but even the most degraded white Australian had more rights than the native. To deprive a person of civil rights was to destroy his self-esteem and his incentive to become a responsible citizen. </p>
</blockquote>
<p>Abdullah displayed the same resolve to achieve equal human rights for Aboriginal people that is evident more than 60 years later in the drive for a Voice to Parliament. He declared:</p>
<blockquote>
<p>We are demanding freedom from restrictive legislation, with equal rights and opportunities as our white brothers and sisters, and then we can join them in developing a greater Australia. </p>
</blockquote>
<h2>Citizenship hearings more akin to criminal trials</h2>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/526737/original/file-20230517-25-1nqed9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/526737/original/file-20230517-25-1nqed9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1055&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526737/original/file-20230517-25-1nqed9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1055&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526737/original/file-20230517-25-1nqed9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1055&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526737/original/file-20230517-25-1nqed9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1326&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526737/original/file-20230517-25-1nqed9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1326&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526737/original/file-20230517-25-1nqed9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1326&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A racist cartoon from the Daily News in Perth from 1944.</span>
<span class="attribution"><span class="source">State Records Office of Western Australia</span></span>
</figcaption>
</figure>
<p>For over a century, Australian states enforced so-called “<a href="https://aiatsis.gov.au/collection/featured-collections/remove-and-protect">protection laws</a>” controlling every aspect of the lives of Aboriginal and Torres Strait Islander people. These laws led to the forcible removal of Indigenous children from their homes and controlled everything from where people lived and worked to their personal relationships and contacts with family and community. </p>
<p>But only Western Australia added citizenship legislation as well, peddling the lie that Aboriginal people had to apply under state law to become “Australian citizens”. Consistent with the national policy of assimilation at the time, one white MP told the state parliament in 1944 that citizenship was an “inspirational measure” for “de-tribalised natives” who lived according to “white standards”. </p>
<p>Government ministers in Western Australia wilfully disregarded the laws of the Commonwealth in setting up this discriminatory system. When introducing the Natives (Citizenship Rights) bill to state parliament in September 1944, A.M. Coverley, the minister for the North-West, claimed, </p>
<blockquote>
<p>The main principle underlying the bill is to provide an opportunity for adult natives to apply for full citizenship as Australians.</p>
</blockquote>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/526937/original/file-20230518-27-1lp7i5.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/526937/original/file-20230518-27-1lp7i5.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=877&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526937/original/file-20230518-27-1lp7i5.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=877&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526937/original/file-20230518-27-1lp7i5.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=877&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526937/original/file-20230518-27-1lp7i5.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1103&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526937/original/file-20230518-27-1lp7i5.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1103&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526937/original/file-20230518-27-1lp7i5.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1103&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A.M. Coverley, WA parliamentarian.</span>
<span class="attribution"><span class="source">Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>After the law was passed, “citizenship” hearings in Western Australia were more like criminal trials, held before a police magistrate with local police as witnesses. Aboriginal applicants suffered the humiliation of intrusive medical examinations and personal inspections of their homes. </p>
<p>The magistrate had to be satisfied the applicant was “of good behaviour and reputation” and “reasonably capable of managing his own affairs”. In addition, applicants had to be “able to speak and understand the English language” and could not be suffering from “active leprosy, syphilis, granuloma or yaws”. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/long-before-the-voice-vote-the-australian-aboriginal-progressive-association-called-for-parliamentary-representation-198064">Long before the Voice vote, the Australian Aboriginal Progressive Association called for parliamentary representation</a>
</strong>
</em>
</p>
<hr>
<p>Some Aboriginal residents in WA refused to take part in the intrusive process.</p>
<p>In 1954, for example, Noongar man George Howard, who described himself as “a Native and […] proud of that fact”, addressed a Rotary luncheon at the Savoy Hotel, Perth. His very presence in the hotel contravened a state prohibition on “natives” entering licensed premises. As Perth’s Daily News pointed out, “he could get full legal rights by getting a certificate of citizenship”. But as Howard <a href="https://trove.nla.gov.au/newspaper/article/266248532?searchTerm=Native%20breaks%20law%20to%20talk%20on%20law">told the audience</a>, </p>
<blockquote>
<p>to get this certificate, I must pay fees and undergo personal investigation by a board, with the end result of being told I am what I am – a natural-born Australian. </p>
</blockquote>
<p>Others who went through the process were mysteriously denied, even if they satisfied all of the requirements. In 1955, Noongar man Jack Shandley, head stockman at Gogo Station near Fitzroy Crossing, travelled 300 kilometres to the Derby magistrates court, declaring he wanted “to be Australian and be free to travel”. However, his application was refused, with no reason given.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/526735/original/file-20230517-27-clvfrg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/526735/original/file-20230517-27-clvfrg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=367&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526735/original/file-20230517-27-clvfrg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=367&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526735/original/file-20230517-27-clvfrg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=367&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526735/original/file-20230517-27-clvfrg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=461&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526735/original/file-20230517-27-clvfrg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=461&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526735/original/file-20230517-27-clvfrg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=461&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A blank copy of a certificate of citizenship form.</span>
<span class="attribution"><span class="source">State Records Office of Western Australia</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-1881-maloga-petition-a-call-for-self-determination-and-a-key-moment-on-the-path-to-the-voice-197796">The 1881 Maloga petition: a call for self-determination and a key moment on the path to the Voice</a>
</strong>
</em>
</p>
<hr>
<h2>A certificate akin to a 'dog tag’</h2>
<p>Even successful applicants faced increased racial harassment, not least being targeted as potential suppliers of liquor. In 1947, for instance, Police Constable C.H. Brown observed suspicious activity on Wellington Street in Perth:</p>
<blockquote>
<p>I saw the native, Sport Charles Jones, holder of the certificate of citizenship No. 152 walking across the street from the direction of the Imperial Hotel. He was carrying two bottles bearing labels, which appeared to be Emu Bitter Beer Labels.</p>
</blockquote>
<p>Jones was convicted and “fined £4 with 4/6 costs” for supplying beer to a “native”.</p>
<p>Aboriginal Australians derided their “certificate of citizenship” as a derogatory <a href="http://www.noongarculture.org.au/wp-content/uploads/2013/07/IntroductiontoNoongarCultureforweb.pdf">“dog licence” or “dog tag”</a>. In 2002, Wongutha man Leo Thomas told the Federal Court:</p>
<blockquote>
<p>When I was about 21 years old […] the football team would go drinking, but if I was caught getting a beer at a hotel my mate would be fined […] The president of the football club asked for me one day they said that we have to go to court […] so they ended up giving me the citizenship rights […] a little black book […] the dog collar, I used to call it.</p>
</blockquote>
<p>Even former soldiers in the Australian armed forces had to show their citizenship “dog tag” to get a drink in a WA pub. </p>
<p>James Brennan enlisted in the army in 1940 and was one of the “Rats of Tobruk” in the second world war, a group of Australian forces who held the Libyan port of Tobruk against German-Italian forces. But as his son-in-law later <a href="https://www.abc.net.au/news/2016-10-17/aboriginal-stockman-turned-guerrilla-fighter/7934792">related</a> to the ABC, </p>
<blockquote>
<p>When he came back from war […] he had to get a citizenship right to go into pubs […] He fought for the country and when he came back home, he couldn’t go into any hotel to get a drink.</p>
</blockquote>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"787868948800737280"}"></div></p>
<h2>Why truth-telling matters</h2>
<p>Courts and policymakers are still making decisions about the lives of Aboriginal and Torres Strait Islander peoples without full knowledge of Indigenous histories and how they continue to affect people today. In our forthcoming book, I argue that even Australia’s highest court has presented a misleading, “whitewashed” view of the history of Indigenous belonging since 1788. </p>
<p>The Voice to Parliament – and the broader goals being sought under the Uluru Statement from the Heart – now offer Australia a chance to confront its history and construct a more inclusive narrative of nationhood. </p>
<p>This history should address the ways in which Australia’s First Peoples were refused equal citizenship and denied the rights and protections that should have accompanied that status. Western Australia’s citizenship law must not be forgotten – it’s an integral part of this story.</p><img src="https://counter.theconversation.com/content/202352/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>For nearly 30 years, Western Australia peddled the lie that Aboriginal people had to apply under state law to become ‘Australian citizens’.Peter Prince, Affiliate of the University of Sydney Law School, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2051882023-05-15T11:47:09Z2023-05-15T11:47:09ZWhat would aliens learn if they observed the Earth? Our study provides an answer<figure><img src="https://images.theconversation.com/files/525346/original/file-20230510-21-a0x73r.jpeg?ixlib=rb-1.1.0&rect=424%2C154%2C4718%2C5150&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Earth seen from orbit around the Moon.</span> <span class="attribution"><span class="source">Nasa</span></span></figcaption></figure><p>Are we alone in the universe? It’s a question that fascinates scientists and the public alike. In science, the focus tends to be on our <a href="https://breakthroughinitiatives.org/initiative/1">search for life elsewhere</a>. The idea that we might be watched by a distant alien civilisation, however, is usually <a href="https://www.goodreads.com/book/show/8909.The_War_of_the_Worlds">confined to the realm of science fiction</a>.</p>
<p>But if there are other technological civilisations out there, they would probably be significantly more developed than we are. After all, we have only just emerged as a fledgling technical (industrial) civilisation in the last 200 years - other technical civilisations could easily be 1,000 or 10,000 or even 100,000 years more advanced than we are.</p>
<p>And no one can deny that the <a href="https://en.wikipedia.org/wiki/Accelerating_change">pace of our own technological progress is accelerating</a>, in some areas at a blistering pace. To paraphrase science fiction author <a href="https://en.wikipedia.org/wiki/Clarke%27s_three_laws">Arthur C. Clarke’s third law</a> - an advanced civilisation would appear to us as capable of magic in terms of their technical prowess. </p>
<p>Over the last few years, my colleagues and I have started to think about whether an advanced civilisation could detect the technological signatures (<a href="https://astrobiology.nasa.gov/news/technosignatures-and-the-search-for-extraterrestrial-intelligence/">“techno-signatures”</a>), such as radio emissions, from Earth. And if so, what might they detect?</p>
<p>Our <a href="https://academic.oup.com/mnras/article/522/2/2393/7028804?login=false">latests study</a> provides a clue.</p>
<p>This isn’t the first time such research has been undertaken. But it’s now more than 50 years since the topic was <a href="https://ui.adsabs.harvard.edu/abs/1978Sci...199..377S/abstract">properly considered</a>. While a lot has changed since the mid-1970s, by far the biggest change has occurred in the last two decades with the advent of mobile phones. These <a href="https://www.simbase.com/learning/how-mobile-networks-work">devices and the towers that connect them</a> have created a new broadband radio emission techno-signature.</p>
<p>Although 4G mobile handsets and transmitting towers are relatively low power individually (0.1-200 watt), there are just so many of them – billions of phones and many millions of towers. And the accumulated radio emission from these is beginning to become quite significant. But would it be noticeable to an alien civilisation watching from afar? We wanted to find out.</p>
<p>It turns out to be rather difficult to find a public database that lists the location and transmitting characteristics of all the mobile towers around the world. But by using the <a href="https://opencellid.org/">OpenCellID database</a>, with data populated by crowdsourcing, we were able to build a simple model estimating the global distribution of mobile towers. </p>
<p>Our model is no doubt crude and incomplete, but it is our best estimate of the techno-signature mobile towers leak out into space. </p>
<p>Because the Earth rotates on its axis, an advanced civilisation located somewhere in our galaxy would measure the radio emission from mobile towers to rise and fall in intensity as different parts of the Earth rotate into view. </p>
<p>The model is complicated by the fact that the transmission of mobile towers is typically beamed towards the horizon. This means that at any given time, towers that are viewed to be setting or rising on the Earth’s horizon will contribute most to the measured signal. </p>
<h2>Alien conclusions?</h2>
<p>An advanced civilisation making many precise measurements of this radio leakage over time could probably conclude that our planet is mostly covered by water and is separated into several major land masses. The radio leakage typically come from the land masses rather than the water. </p>
<p>They might also be able to tell that while most of the mobile radio leakage is associated with land masses, the towers (and presumably their intelligent users) tend to be situated along the coastline. </p>
<p>They would also see that mobile tower networks are quite equitably distributed across the planet. That’s different to the traditional radio leakage previously recognised as major techno-signatures – in particular, radar and TV transmitters. </p>
<p>Our simulations show that significant contributions to the Earth’s mobile leakage radiation is being made by developing regions, such as Africa and Asia. This is no surprise given the <a href="https://toppandigital.com/translation-blog/mobile-technology-transforming-africa/">importance of mobile systems</a> in all aspects of society in developing countries. </p>
<p>We calculated the power emitted from Earth – which is about 4 gigawatt (GW) in total at its peak (one GW could power around 750,000 homes for an hour). We estimated the transmission as viewed from three different stars in our galaxy – <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/Starlog/lalande.html">HD 95735</a>, <a href="https://earthsky.org/astronomy-essentials/barnards-star-closest-stars-famous-stars/">Barnard’s star,</a> and <a href="https://earthsky.org/brightest-stars/alpha-centauri-is-the-nearest-bright-star/">Alpha Centauri A</a>. </p>
<p>We worked out that an alien civilisation near these locations would, however, need much better telescopes than we have to detect the Earth’s mobile radio leakage. But that would be quite probable, given most technical civilisations are expected to be much more advanced than we are. </p>
<p>There are also other types of emissions they could see, such as military radar systems and deep space communication transmissions to distant spacecraft, such as the Voyager space probes. While these signals would be relatively rare events for an observing alien, they have the advantage of being extremely powerful. </p>
<figure class="align-center ">
<img alt="Radio telescope under the Milky Way." src="https://images.theconversation.com/files/525581/original/file-20230511-23-ildy0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/525581/original/file-20230511-23-ildy0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/525581/original/file-20230511-23-ildy0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/525581/original/file-20230511-23-ildy0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/525581/original/file-20230511-23-ildy0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/525581/original/file-20230511-23-ildy0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/525581/original/file-20230511-23-ildy0.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">Do aliens have radio telescopes?</span>
<span class="attribution"><span class="source">zhengzaishuru/Shutterstock</span></span>
</figcaption>
</figure>
<p>Radio techno-signatures are probably the defining characteristic of our own civilisation’s existence, at least from an alien’s perspective. But an extraterrestrial species would also find leakage radiation across the electromagnetic spectrum (including visible light).</p>
<p>If we continue to increase our energy consumption at the current rate, <a href="https://energyeducation.ca/encyclopedia/Waste_heat">“waste-heat”</a> – an unavoidable end-product of energy usage – will also be discharged into space. There it would manifest itself as an anomalous excess at infra-red wavelengths – a telltale sign of an active technical civilisation. </p>
<p>Other techno-signatures including <a href="https://ui.adsabs.harvard.edu/abs/2021ApJ...908..164K/abstract">industrial pollutants</a> in the Earth’s atmosphere would also be noticeable to aliens equipped with powerful telescopes and spectral analysis systems (which break down light according to wavelength). An advanced alien civilisation could no doubt have a good guess at our particular phase of industrialisation and our energy consumption. </p>
<p>On Earth, we use the <a href="https://www.universetoday.com/153167/what-is-the-kardashev-scale/">Kardashev scale</a> for estimating the development of alien civilisations based on their energy usage - on that scale we’d appear as an emerging technical civilisation, not yet on the bottom rung of the ladder. </p>
<p>And even if an alien species failed to detect all this at the moment, they might do better very soon. We plan to extend this work to include traditional radio techno-signatures and other emerging sources of radio leakage radiation, including 5G systems, wifi, digital transmissions and deep space communications. </p>
<p>This would also include the cocoon of radio emission that will soon surround the Earth as the growth of huge <a href="https://www.iau.org/public/themes/satellite-constellations/">satellite constellations</a> such as Starlink and OneWeb provide global <a href="https://theconversation.com/starlink-amazon-and-others-are-racing-to-fill-the-sky-with-bigger-satellites-to-deliver-mobile-coverage-everywhere-on-earth-190237">wifi coverage</a>. </p>
<p>Who knows, it might even be possible for aliens to decode the complex modulation of our mobile communication systems. Ultimately, as the Earth becomes artificially brighter at all wavelengths, the chances that they detect us before we detect them, cannot be ruled out.</p><img src="https://counter.theconversation.com/content/205188/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Garrett 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>The accumulated radio emission from mobile phones on Earth is beginning to become quite significant.Michael Garrett, Sir Bernard Lovell chair of Astrophysics and Director of Jodrell Bank Centre for Astrophysics, University of ManchesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2032072023-04-10T12:10:25Z2023-04-10T12:10:25ZJupiter’s moons hide giant subsurface oceans – two missions are sending spacecraft to see if these moons could support life<figure><img src="https://images.theconversation.com/files/519960/original/file-20230407-28-6r7tcb.jpg?ixlib=rb-1.1.0&rect=51%2C27%2C2224%2C1425&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The surface of Europa – one of Jupiter's moons – is a thick layer of solid ice.</span> <span class="attribution"><a class="source" href="https://solarsystem.nasa.gov/resources/204/europas-stunning-surface/?category=moons/jupiter-moons_europa">NASA/JPL-Caltech/SETI Institute</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>On April 13, 2023, the European Space Agency launched a rocket carrying a spacecraft destined for Jupiter. The <a href="https://www.esa.int/Science_Exploration/Space_Science/Juice">Jupiter Icy Moons Explorer</a> – or JUICE – will spend at least three years on Jupiter’s moons after it arrives in 2031. In October 2024, NASA is also planning to launch a robotic spacecraft named <a href="https://europa.nasa.gov/">Europa Clipper</a> to the Jovian moons, highlighting an increased interest in these distant, but fascinating, places in the solar system.</p>
<p><a href="https://www.michaelmsori.com/">I’m a planetary scientist</a> who studies the <a href="https://scholar.google.com/citations?user=NLWIrYoAAAAJ&hl=en&oi=ao">structure and evolution of solid planets and moons</a> in the solar system. </p>
<p>There are many reasons my colleagues and I are looking forward to getting the data that JUICE and Europa Clipper will hopefully be sending back to Earth in the 2030s. But perhaps the most exciting information will have to do with water. Three of Jupiter’s moons – Europa, Ganymede and Callisto – are home to large, underground oceans of liquid water that could support life.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four moons next to a large red spot on the surface of Jupiter." src="https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=857&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=857&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=857&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1077&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1077&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1077&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 composite image shows, from top to bottom, Io, Europa, Ganymede and Callisto next to Jupiter.</span>
<span class="attribution"><a class="source" href="https://solarsystem.nasa.gov/resources/2662/family-portrait-of-the-jovian-system/?category=moons/jupiter-moons_europa">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Meet Io, Europa, Ganymede and Callisto</h2>
<p>Jupiter has dozens of moons. Four of them in particular are of interest to planetary scientists.</p>
<p>Io, Europa, Ganymede and Callisto are, like Earth’s Moon, relatively large, spherical complex worlds. Two previous NASA missions have sent spacecraft to orbit the Jupiter system and collected data on these moons. The <a href="https://solarsystem.nasa.gov/missions/galileo/overview/">Galileo mission</a> orbited Jupiter from 1995 to 2003 and led to geological discoveries on all four large moons. The <a href="https://www.nasa.gov/mission_pages/juno/main/index.html">Juno mission</a> is still orbiting Jupiter today and has provided scientists with an unprecedented view into Jupiter’s composition, structure and space environment. </p>
<p>These missions and other observations revealed that Io, the closest of the four to its host planet, is <a href="https://doi.org/10.1146/annurev.earth.31.100901.145428">abuzz with</a> <a href="https://doi.org/10.1038/nature22339">geological activity</a>, including lava lakes, volcanic eruptions and tectonically formed mountains. But it is not home to large amounts of water.</p>
<p>Europa, Ganymede and Callisto, in contrast, have icy landscapes. Europa’s surface is a frozen wonderland with a young but complex history, <a href="https://doi.org/10.1038/ngeo2245">possibly including icy analogs</a> of plate tectonics and volcanoes. Ganymede, the largest moon in the entire solar system, is bigger than Mercury and has its own magnetic field <a href="https://doi.org/10.1038/384544a0">generated internally from a liquid metal core</a>. Callisto appears somewhat inert compared to the others, but serves as a valuable time capsule of an ancient past that is no longer accessible on the youthful surfaces of Europa and Io.</p>
<p>Most exciting of all: Europa, Ganymede and Callisto all almost certainly possess <a href="https://www.nasa.gov/specials/ocean-worlds/">underground oceans of liquid water</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing a cutaway of Europa." src="https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=570&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=570&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=570&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=716&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=716&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=716&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Warmth from Europa’s interior and tidal energy from Jupiter likely maintain a massive liquid ocean beneath the moon’s icy surface.</span>
<span class="attribution"><a class="source" href="https://photojournal.jpl.nasa.gov/jpeg/PIA24477.jpg">NASA/JPL-Caltech/Michael Carroll</a></span>
</figcaption>
</figure>
<h2>Ocean worlds</h2>
<p>Europa, Ganymede and Callisto have chilly surfaces that are <a href="https://europa.nasa.gov/resources/114/daytime-temperatures-on-europa/">hundreds of degrees below zero</a>. At these temperatures, ice behaves like solid rock. </p>
<p>But <a href="https://theconversation.com/how-has-the-inside-of-the-earth-stayed-as-hot-as-the-suns-surface-for-billions-of-years-193277">just like Earth</a>, the deeper underground you go on these moons, the hotter it gets. Go down far enough and you eventually reach the temperature where ice melts into water. Exactly how far down this transition occurs on each of the moons is a <a href="https://doi.org/10.1016/j.icarus.2005.03.013">subject of debate</a> that scientists hope to resolve with JUICE and Europa Clipper. While the exact depths are still uncertain, scientists are confident that these oceans exist. </p>
<p>The best evidence of these oceans comes from Jupiter’s magnetic field. Saltwater is electrically conductive. So as these moons travel through Jupiter’s magnetic field, they <a href="https://doi.org/10.1126/science.289.5483.1340">generate a secondary, smaller magnetic field</a> that signals to researchers the presence of an underground ocean. Using this technique, planetary scientists have been able to show that the three <a href="https://doi.org/10.1038/27394">moons contain underground oceans</a>. And these oceans are not small – Europa’s ocean alone might have more than <a href="https://solarsystem.nasa.gov/moons/jupiter-moons/europa/overview/">double the water</a> of all of Earth’s oceans combined.</p>
<p>An obvious and tantalizing next question is whether these oceans can support extraterrestrial life. Liquid water is an important piece of what makes for a habitable world, but far from the only requirement for life. Life also needs <a href="https://astrobiology.nasa.gov/education/primer/">energy and certain chemical compounds</a> in addition to water to flourish. Because these oceans are hidden beneath miles of solid ice, <a href="https://doi.org/10.1126/science.1060081">sunlight and photosynthesis are out</a>. But it’s possible other sources could provide the needed ingredients.</p>
<p>On Europa, for example, the liquid water ocean <a href="https://solarsystem.nasa.gov/moons/jupiter-moons/europa/overview/">overlays a rocky interior</a>. That rocky seafloor could provide energy and chemicals through underwater volcanoes that could make Europa’s ocean habitable. But it is also possible that Europa’s ocean is a sterile, inhospitable place – scientists need more data to answer these questions. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Artist's impression of the JUICE spacecraft approaching Jupiter and the jovian moons." src="https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=339&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=339&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=339&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=426&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=426&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=426&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 Jupiter Icy Moons Explorer spacecraft will travel for eight years before reaching Jupiter.</span>
<span class="attribution"><a class="source" href="https://sci.esa.int/web/juice/-/59334-exploring-jupiter">ESA/ATG medialab/NASA/JPL/University of Arizona/J. Nichols</a></span>
</figcaption>
</figure>
<h2>Upcoming missions from ESA and NASA</h2>
<p>JUICE and Europa Clipper are set up to give scientists game-changing information about the potential habitability of Jupiter’s moons. While both missions will gather data on multiple moons, JUICE will spend time orbiting and focusing on Ganymede, and Europa Clipper will make dozens of close flybys of Europa.</p>
<p>Both of the spacecraft will carry a suite of scientific instruments built specifically to investigate the oceans. Onboard radar will allow JUICE and Europa Clipper <a href="https://rslab.disi.unitn.it/rime/">to probe into the moons’</a> <a href="https://europa.nasa.gov/spacecraft/instruments/reason/">outer layers of solid ice</a>. Radar could reveal any small pockets of liquid water in the ice, or, in the case of Europa, which has a thinner outer ice layer than Ganymede and Callisto, <a href="https://doi.org/10.1016/j.icarus.2016.08.014">hopefully detect the larger ocean</a>. </p>
<p><a href="https://europa.nasa.gov/spacecraft/instruments/ecm/">Magnetometers will also be</a> <a href="https://www.esa.int/Science_Exploration/Space_Science/Juice_factsheet">on both missions</a>. These tools will give scientists the opportunity to study the secondary magnetic fields produced by the interaction of conductive oceans with Jupiter’s field in great detail and will hopefully give researchers clues to salinity and volumes of the oceans. </p>
<p>Scientists will also observe small variations in the moons’ gravitational pulls by tracking subtle movements in both spacecrafts’ orbits, which could help determine if Europa’s seafloor has volcanoes that <a href="https://doi.org/10.1016/j.icarus.2019.02.025">provide the needed energy and chemistry</a> for the ocean to support life.</p>
<p>Finally, both craft will carry a host of cameras and light sensors that will provide unprecedented images of the geology and composition of the moons’ icy surfaces. </p>
<p>Maybe one day, a spacecraft will be able to drill through the miles of solid ice on Europa, Ganymede or Callisto and explore oceans directly. Until then, observations from spacecraft like JUICE and Europa Clipper are scientists’ best bet for learning about these ocean worlds.</p>
<p>When Galileo discovered these moons in 1609, they were the first objects known to directly orbit another planet. Their discovery was the final nail in the coffin of the theory that Earth – and humanity – resides at the center of the universe. Maybe these worlds have another humbling surprise in store.</p><img src="https://counter.theconversation.com/content/203207/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Sori receives funding from NASA. </span></em></p>The Jupiter Icy Moons Explorer and Europa Clipper missions will arrive at Jupiter in the 2030s and provide researchers with unprecedented access to the icy moons orbiting the gas giant.Mike Sori, Assistant Professor of Planetary Science, Purdue UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1972912023-03-13T16:38:54Z2023-03-13T16:38:54ZStarseeds: psychologists on why some people think they’re aliens living on Earth<figure><img src="https://images.theconversation.com/files/514273/original/file-20230308-24-wolhb3.jpg?ixlib=rb-1.1.0&rect=53%2C0%2C6000%2C3979&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Welcome to the new reality.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/double-exposure-portrait-young-woman-close-1723327936">sun ok/Shutterstock</a></span></figcaption></figure><p>There’s a new group of people on Earth who believe they’re aliens.
Star people, or <a href="https://brill.com/display/book/9789004435537/BP000031.xml">starseeds</a>, are individuals who believe they have come to Earth from other dimensions to help heal the planet and guide humanity into the “golden age” – a period of great happiness, prosperity and achievement. </p>
<p>It might sound a little crazy but an internet search for the term brings up over 4 million results and there are scores of people posting videos on TikTok, <a href="https://www.instagram.com/explore/tags/starseed/?hl=en">Instagram</a> and Facebook who believe they originate from another world. Indeed, content with the term <a href="https://www.tiktok.com/tag/starseed?lang=en">#starseed</a> has over 1 billion views on TikTok.</p>
<p>Unlike “Earth souls”, who are said to reincarnate on Earth, starseeds believe they have reawakened from another planet to be born here. <a href="https://www.simonandschuster.com/books/The-Beginners-Guide-to-Starseeds/Whitney-Jefferson-Evans/9781507215364">Starseeds believe</a> they are conduits between divine realms and the Earth and that they can transport between galaxies via <a href="https://insighttimer.com/hypnolution/guided-meditations/starseed-activation-meditation">meditation</a>. Starseeds also believe they can communicate in “<a href="https://blog.mindvalley.com/light-language/">light language</a>” – a form of communication that is said to bypass human limitations and be the language of the soul.</p>
<p>The idea is widely credited to the author <a href="https://www.waterstones.com/author/brad-steiger/320608">Brad Steiger</a> who wrote prolifically about the unknown and was keenly interested in alien life and extraterrestrials. In his 1976 book, <a href="https://www.goodreads.com/en/book/show/894911">Gods of Aquarius</a>, Steiger introduced his notion that some people originate from other dimensions. </p>
<p>Believers claim there are several ways to tell if you are a starseed. These include searching for meaning in life and feeling a lack of belonging. Being spiritual and possessing a strong sense of intuition (knowing) are also qualities of a starseed. </p>
<p>They are also said to be empathetic, sensitive and have more <a href="https://books.google.co.uk/books?hl=en&lr=&id=q8L657GHi6kC&oi=fnd&pg=PA1&dq=starseed+mental+and+physical+health+problems&ots=YZ263SVYMB&sig=rbmofx2MVrP6MExxKJjQkkmszX0#v=onepage&q=starseed%20mental%20and%20physical%20health%20problems&f=false">physical and mental health issues</a> as their souls aren’t used to having a human body. Starseeds want to help humanity. But they get overwhelmed by life on Earth and so recharge by spending time alone.</p>
<p>Believers also say that starseeds have the desire to explore and experience new cultures and spheres, which help star people to then provide novel insights into existence. Examples include <a href="https://theconversation.com/conspiracy-theories-start-to-take-hold-at-age-14-study-suggests-156006">new (conspiracy) theories</a> about society, holistic health interventions along with thoughts on <a href="https://www.nationalgeographic.com/travel/article/ancient-sites-built-by-aliens">ancient aliens and civilisations</a>.</p>
<h2>Choose your reality</h2>
<p>You might recognise some aspects of yourself in the above description. Many people, for example, report <a href="https://www.pewresearch.org/global/2021/11/18/finding-meaning-in-what-one-does/">searching for meaning in life</a> along with <a href="https://www.tandfonline.com/doi/full/10.1080/00332747.2015.1015867">feeling displaced</a> or like they <a href="https://www8.gsb.columbia.edu/newsroom/newsn/11261/feeling-like-you-dont-belong-racial-and-identity-based-insults-and-slights-can-lower-self-esteem-and-damage-quality-of-life">don’t belong</a> at times. </p>
<p>Indeed, <a href="https://www.tandfonline.com/doi/full/10.1080/00332747.2015.1015867#:%7E:text=Conclusions%3A%20Sense%20of%20belonging%20is,in%20the%20treatment%20of%20depression.">research shows</a> that a low sense of belonging is often linked to depression. But what makes some people who are experiencing such feelings <a href="https://www.theguardian.com/lifeandstyle/2021/oct/17/eva-wiseman-conspirituality-the-dark-side-of-wellness-how-it-all-got-so-toxic">jump to the conclusion</a> that they must be from another planet? Particularly given that no life beyond Earth has ever been found and there is <a href="https://astrobiology.nasa.gov/about/">no evidence</a> that alien life has ever visited Earth.</p>
<p>Welcome to the <a href="https://neurofied.com/barnum-effect-the-reason-why-we-believe-our-horoscopes/">Forer effect</a>. Named after <a href="http://apsychoserver.psych.arizona.edu/jjbareprints/psyc621/forer_the%20fallacy%20of%20personal%20validation_1949.pdf">Bertram Forer</a>, the psychologist who first figured out that it was pretty easy to get people to agree with vague descriptions about themselves – see horoscopes.</p>
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<p>The concept of starseeds is a form of <a href="https://www.icsahome.com/articles/what-is-new-age-langone">new age belief</a>. The term refers to <a href="https://link.springer.com/referenceworkentry/10.1007/978-3-319-08956-0_78-1">alternative spiritual practices</a> that developed during the 1970s. </p>
<p>Although each <a href="https://www.pewresearch.org/fact-tank/2018/10/01/new-age-beliefs-common-among-both-religious-and-nonreligious-americans/">new age belief</a> is different, philosophies share common features: they view existence in terms of the universe and focus on spirituality as well as <a href="https://www.tandfonline.com/doi/full/10.1080/10253860500241930?casa_token=Rz5YQdqjZhcAAAAA%3A_g8SOXBuZsO5Ftgb4lWC7AnBRgnbB1TtAFM9LJUS1Ru7K9jTJvLlz4pIt8e1eLj9LBWyDH6UEO">the self</a>. Think crystals, energy healing and <a href="https://theconversation.com/the-science-of-why-so-many-people-believe-in-psychic-powers-102088">psychic abilities</a>.</p>
<p>Other features include <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3705678/#:%7E:text=Reincarnation%20is%20the%20religious%20or,of%20the%20previous%20life's%20actions.">reincarnation</a>, <a href="https://www.livescience.com/41462-what-is-karma.html">karma</a> and the possibility of reaching a <a href="https://www.sciencedirect.com/science/article/pii/S136466131630002X">higher level of consciousness</a>.</p>
<p>Support for <a href="https://psycnet.apa.org/record/2012-21330-003">new age beliefs</a> – such as starseeds – is <a href="https://www.pewresearch.org/fact-tank/2018/10/01/new-age-beliefs-common-among-both-religious-and-nonreligious-americans/">on the rise</a>. It comes from a <a href="https://www.sciencealert.com/distrust-in-science-is-causing-harm-but-these-researchers-have-a-plan#:%7E:text=Distrust%20of%20science%20is%20a,often%20stickier%20than%20the%20truth.">distrust of science</a> and doubts about <a href="https://theconversation.com/is-reality-a-game-of-quantum-mirrors-a-new-theory-suggests-it-might-be-162936">conventional perceptions of reality</a>. Particularly, cynicism about <a href="https://apnews.com/article/covid-technology-health-government-and-politics-new-york-cfb56a95aec23dddbabcf3ebbe839f05">modern society</a> and an attempt to find meaning in life. </p>
<h2>Fantasy v fiction</h2>
<p>Certain personality characteristics may also incline some people to believe in the notion of starseeds. For instance, if you are <a href="https://metro.co.uk/2020/09/11/overactive-imagination-you-might-have-a-fantasy-prone-personality-type-13247464/">fantasy prone</a> and often confuse imaginary and real events you may see the theory of alien consciousness as profound and desirable.</p>
<p>In psychological terms, this is known as a <a href="https://escholarship.org/content/qt2t1731dw/qt2t1731dw.pdf">source monitoring error</a>, which is a type of unconscious memory error whereby a person gets confused between what’s real and accurate and what’s unreal and imagined. </p>
<p>It’s commonly seen in schizophrenia and research has found links between <a href="https://www.sciencedirect.com/science/article/abs/pii/S0165178117312301">schizotypal personality disorder</a> – a common disorder considered to be a mild form of schizophrenia – and belief in conspiracy theories.</p>
<p>A further effect that can encourage such beliefs is what’s known as <a href="https://journals.sagepub.com/doi/full/10.1177/2158244018809874#:%7E:text=Ontological%20confusion%20is%20a%20set,possibly%20caused%20by%20categorical%20trespassing.">ontological confusion</a>. This occurs when people cannot discriminate between <a href="https://www.psypost.org/2018/11/people-who-are-religious-and-ontologically-confused-are-more-likely-to-share-pseudo-profound-bullshit-52583#:%7E:text=For%20example%2C%20ontologically%2Dconfused%20people,more%20likely%20to%20be%20shared.">metaphorical and factual</a> statements such as: “Old furniture knows things about the past.” These may be interpreted more literally than metaphorically and so make it more likely that people then endorse pseudoscientific, transcendental theories. </p>
<p>This is especially true when the source of the information is perceived to be trustworthy and knowledgeable. Dubbed <a href="https://www.sciencealert.com/the-einstein-effect-people-trust-nonsense-from-scientists-more-than-spiritual-gurus#:%7E:text=The%20authors%20think%20their%20results,the%20social%20credibility%20they%20possess.">the Einstein effect</a>, this is where trusted sources of information are given more credence because of the social credibility they possess. </p>
<p>In the case of starseeds, <a href="https://www.waterstones.com/book/letters-to-a-starseed/rebecca-campbell/9781788175876">several books</a> published by <a href="https://www.simonandschuster.co.uk/books/The-Beginners-Guide-to-Starseeds/Whitney-Jefferson-Evans/9781507215371">big publishing houses</a> may provide a sense of authenticity and so too does the fact that a number of them are bestsellers. Indeed, it seems life as we know it, may not be as straightforward as we once imagined.</p><img src="https://counter.theconversation.com/content/197291/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>We’ve spent ages learning about the people who think they’ve come from another planet, so you don’t have to.Ken Drinkwater, Senior Lecturer and Researcher in Cognitive and Parapsychology, Manchester Metropolitan UniversityAndrew Denovan, Senior Lecturer in Psychology, University of HuddersfieldNeil Dagnall, Reader in Applied Cognitive Psychology, Manchester Metropolitan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1982742023-03-08T13:41:07Z2023-03-08T13:41:07ZDistant star TOI-700 has two potentially habitable planets orbiting it – making it an excellent candidate in the search for life<figure><img src="https://images.theconversation.com/files/512978/original/file-20230301-18-2jg7dp.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1859%2C1034&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The TOI-700 star system is home to four planets, including two in its habitable zone that could host liquid water.</span> <span class="attribution"><a class="source" href="https://www.jpl.nasa.gov/spaceimages/images/largesize/PIA23408_hires.jpg">NASA's Goddard Space Flight Center</a></span></figcaption></figure><p>NASA recently announced the <a href="https://doi.org/10.3847/2041-8213/acb599">discovery of a new, Earth-sized planet</a> in the habitable zone of a nearby star called TOI-700. <a href="https://sites.google.com/site/josepherodriguezjr/">We are</a> <a href="https://avanderburg.github.io/">two of</a> the astronomers who led the discovery of this planet, called TOI-700 e. TOI-700 e is just over 100 light years from Earth – too far away for humans to visit – but we do know that it is similar in size to the Earth, likely rocky in composition and could potentially support life.</p>
<p>You’ve probably heard about some of the <a href="https://exoplanets.nasa.gov/trappist1/">many</a> <a href="https://www.eso.org/public/news/eso1629/">other</a> <a href="https://www.nasa.gov/press-release/nasa-kepler-mission-discovers-bigger-older-cousin-to-earth">exoplanet</a> <a href="https://www.nasa.gov/image-feature/kepler-1649c-earth-size-habitable-zone-planet-hides-in-plain-sight">discoveries</a> in <a href="https://www.nasa.gov/mission_pages/kepler/news/kepscicon-briefing.html">recent</a> years. In fact, TOI-700 e is one of two potentially habitable planets just in the TOI-700 star system. </p>
<p>Habitable planets are those that are just the right distance from their star to have a surface temperature that could sustain liquid water. While it is always exciting to find a new, potentially habitable planet far from Earth, the focus of exoplanet research is shifting away from simply discovering more planets. Instead, researchers are focusing their efforts on finding and studying systems most likely to answer key questions about how planets form, how they evolve, and whether life might exist in the universe. TOI-700 e stands out from many of these other planet discoveries because it is well suited for future studies that could help answer big question about the conditions for life outside the solar system. </p>
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<figcaption><span class="caption">Specific methods for detecting exoplanets, like the transit method, which looks for a dip in the light coming from a distant star as a planet passes in front of it, have led to an explosion in the number of known exoplanets.</span></figcaption>
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<h2>From 1 to 5,000</h2>
<p>Astronomers discovered the first exoplanet around a Sun-like star <a href="https://doi.org/10.1038/378355a0">in 1995</a>. The field of exoplanet discovery and research has been rapidly evolving ever since.</p>
<p>At first, astronomers were finding only a <a href="https://www.hughosborn.co.uk/2015/02/09/a-history-of-planet-detection-in-one-animation/">few exoplanets each year</a>, but the combination of new cutting-edge facilities focused on <a href="https://www.nasa.gov/tess-transiting-exoplanet-survey-satellite">exoplanet science</a> with improved detection sensitivity have led to astronomers’ discovering hundreds of exoplanets each year. As detection methods and tools have improved, the amount of information scientists can learn about these planets has increased. In 30 years, scientists have gone from barely being able to detect exoplanets to <a href="https://theconversation.com/to-search-for-alien-life-astronomers-will-look-for-clues-in-the-atmospheres-of-distant-planets-and-the-james-webb-space-telescope-just-proved-its-possible-to-do-so-184828">characterizing key chemical clues in their atmospheres</a>, like water, using facilities like the James Webb Space Telescope.</p>
<p>Today, there are more than <a href="https://exoplanetarchive.ipac.caltech.edu/">5,000 known exoplanets</a>, ranging from gas giants to small rocky worlds. And perhaps most excitingly, astronomers have now found about a dozen exoplanets that are likely rocky and orbiting within the habitable zones of their respective stars.</p>
<p>Astronomers have even discovered a few systems – like TOI-700 – that have more than one planet orbiting in the habitable zone of their star. We call these keystone systems.</p>
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<a href="https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing a star with a green ring around it marking the habitable zone." src="https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=185&fit=crop&dpr=1 600w, https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=185&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=185&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=233&fit=crop&dpr=1 754w, https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=233&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/512975/original/file-20230301-24-8pqinb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=233&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The TOI-700 system has a large habitable zone, and the newly discovered TOI-700 e, not shown in this image, orbits the star along the inner edge of the habitable zone.</span>
<span class="attribution"><a class="source" href="https://www.jpl.nasa.gov/spaceimages/images/largesize/PIA23407_hires.jpg">NASA's Goddard Space Flight Center</a></span>
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<h2>A pair of habitable siblings</h2>
<p>TOI-700 first made headlines when our team announced the discovery of <a href="https://doi.org/10.3847/1538-3881/aba4b2">three small planets orbiting the star</a> in early 2020. Using a <a href="https://doi.org/10.3847/1538-3881/aba4b3">combination of observations</a> from NASA’s <a href="https://exoplanets.nasa.gov/tess/">Transiting Exoplanet Surveying Satellite</a> mission and the <a href="https://www.nasa.gov/mission_pages/spitzer/main/index.html">Spitzer Space Telescope</a> we discovered these planets by measuring small dips in the amount of light coming from TOI-700. These dips in light are caused by planets passing in front of the small, cool, red dwarf star at the center of the system.</p>
<p>By taking precise measurements of the changes in light, we were able to determine that at least three small planets are in the TOI-700 system, with hints of a possible fourth. We could also determine that the third planet from the star, TOI-700 d, orbits within its star’s habitable zone, where the temperature of the planet’s surface could allow for liquid water. </p>
<p>The Transiting Exoplanet Surveying Satellite observed TOI-700 for another year, from July 2020 through May 2021, and using these observations <a href="https://doi.org/10.3847/2041-8213/acb599">our team found the fourth planet, TOI-700 e</a>. TOI-700 e is 95% the size of the Earth and, much to our surprise, orbits on the inner edge of the star’s habitable zone, between planets c and d. Our discovery of this planet makes TOI-700 one of only a few known systems with two Earth-sized planets orbiting in the habitable zone of their star. The fact that it is relatively close to Earth also makes it one of the most accessible systems in terms of future characterization.</p>
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<a href="https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="James Webb Space Telescope against the backdrop of space." src="https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=467&fit=crop&dpr=1 600w, https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=467&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=467&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=586&fit=crop&dpr=1 754w, https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=586&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/512981/original/file-20230301-24-v7fzr8.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"></a>
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<span class="caption">New tools, like the James Webb Space Telescope, can provide clues about life on distant planets, but with thousands of scientific questions to answer, efficient use of time is key.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:James_Webb_Space_Telescope.jpg#/media/File:James_Webb_Space_Telescope.jpg">Bricktop/Wikimedia Commons</a></span>
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<h2>The bigger questions and tools to answer them</h2>
<p>With the successful launch of the James Webb Space Telescope, astronomers are now able to start <a href="https://www.nasa.gov/feature/goddard/2022/nasa-s-webb-reveals-an-exoplanet-atmosphere-as-never-seen-before">characterizing the atmospheric chemistry</a> of exoplanets and search for <a href="https://theconversation.com/to-search-for-alien-life-astronomers-will-look-for-clues-in-the-atmospheres-of-distant-planets-and-the-james-webb-space-telescope-just-proved-its-possible-to-do-so-184828">clues about whether life exists</a> on them. In the near future, a number of massive, ground-based telescopes will also help reveal further details about the composition of planets far from the solar system. </p>
<p>But even with powerful new telescopes, collecting enough light to learn these details requires pointing the telescope at a system for a <a href="https://arxiv.org/abs/1708.04239">long period of time</a>. With thousands of <a href="https://www.stsci.edu/jwst/science-execution/approved-programs/cycle-1-go">valuable scientific questions to answer</a>, astronomers need to know where to look. And that is the goal of our team, to find the most interesting and promising exoplanets to study with the Webb telescope and future facilities.</p>
<p>Earth is currently the only data point in the search for life. It is possible alien life could be vastly different from life as we know it, but for now, places similar to the home of humanity with liquid water on the surface offer a good starting point. We believe that keystone systems with multiple planets that are likely candidates for hosting life – like TOI-700 – offer the best use of observation time. By further studying TOI-700, our team will be able to learn more about what makes a planet habitable, how rocky planets similar to Earth form and evolve, and the mechanisms that shaped the solar system. The more astronomers know about how star systems like TOI-700 and our own solar system work, the better the chances of detecting life out in the cosmos.</p><img src="https://counter.theconversation.com/content/198274/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Joseph Rodriguez receives funding from the National Aeronautics and Space Administration and Michigan State University. </span></em></p><p class="fine-print"><em><span>Andrew Vanderburg receives funding from the National Aeronautics and Space Administration and the Massachusetts Institute of Technology. </span></em></p>With more than 5,000 known exoplanets, astronomers are shifting their focus from discovering additional distant worlds to identifying which are good candidates for further study.Joey Rodriguez, Assistant Professor of Physics and Astronomy, Michigan State UniversityAndrew Vanderburg, Assistant Professor of Physics, Massachusetts Institute of Technology (MIT)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1976212023-03-03T00:13:56Z2023-03-03T00:13:56ZHumans are still hunting for aliens. Here’s how astronomers are looking for life beyond Earth<figure><img src="https://images.theconversation.com/files/508029/original/file-20230203-12-uvmpl6.jpg?ixlib=rb-1.1.0&rect=302%2C315%2C4072%2C2733&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">zhengzaishuru/Shutterstock</span></span></figcaption></figure><p>We have long been fascinated with the idea of alien life. The earliest written record presenting the idea of “aliens” is seen in the satiric work of Assyrian writer <a href="https://blogs.scientificamerican.com/life-unbounded/the-first-alien/">Lucian of Samosata</a> dated to 200 AD.</p>
<p>In one novel, Lucian <a href="https://www.yorku.ca/inpar/lucian_true_tale.pdf">writes of a journey to the Moon</a> and the bizarre life he imagines living there – everything from three-headed vultures to fleas the size of elephants.</p>
<p>Now, 2,000 years later, we still write stories of epic adventures beyond Earth to meet otherworldly beings (<a href="https://www.britannica.com/topic/The-Hitchhikers-Guide-to-the-Galaxy-novel-by-Adams">Hitchhiker’s Guide</a>, anyone?). Stories like these entertain and inspire, and we are forever trying to find out if science fiction will become science fact.</p>
<h2>Not all alien life is the same</h2>
<p>When looking for life beyond Earth, we are faced with two possibilities. We might find basic microbial life hiding somewhere in our Solar System; or we will identify signals from intelligent life somewhere far away.</p>
<p>Unlike in <a href="https://www.britannica.com/topic/Star-Wars-film-series">Star Wars</a>, we’re not talking far, far away in another galaxy, but rather around other nearby stars. It is this second possibility which really excites me, and should excite you too. A detection of intelligent life would fundamentally change how we see ourselves in the Universe. </p>
<p>In the last 80 years, programs dedicated to the search for extraterrestrial intelligence (SETI) have worked tirelessly searching for cosmic “hellos” in the form of radio signals.</p>
<p>The reason we think any intelligent life would communicate via radio waves is due to the waves’ ability to travel vast distances through space, rarely interacting with the dust and gas in between stars. If anything out there is trying to communicate, it’s a pretty fair bet they would do it through radio waves. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=134&fit=crop&dpr=1 600w, https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=134&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=134&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=169&fit=crop&dpr=1 754w, https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=169&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/505679/original/file-20230121-18-zi7kes.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=169&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 three radio facilities used in the Breakthrough Listen Initiative. Left to Right: 100m Robert C. Byrd Green Bank Telescope, 64m Murriyang (Parkes) Radio Telescope, 64-antenna MeerKAT array.</span>
<span class="attribution"><span class="source">NRAO, CSIRO, MeerKAT</span></span>
</figcaption>
</figure>
<h2>Listening to the stars</h2>
<p>One of the most exciting searches to date is <a href="https://breakthroughinitiatives.org/initiative/1">Breakthrough Listen</a>, the largest scientific research program dedicated to looking for evidence of intelligent life beyond Earth.</p>
<p>This is one of many projects funded by US-based Israeli entrepreneurs Julia and Yuri Milner, with some serious dollars attached. Over a ten-year period a total amount of <a href="https://breakthroughinitiatives.org/initiative/1">US$100 million</a> will be invested in this effort, and they have a mighty big task at hand. </p>
<p>Breakthrough Listen is currently targeting the closest one million stars in the hope of identifying any unnatural, alien-made radio signals. Using telescopes around the globe, from the 64-metre Murriyang Dish (Parkes) here in Australia, to the 64-antenna MeerKAT array in South Africa, the search is one of epic proportions. But it isn’t the only one. </p>
<p>Hiding away in the Cascade Mountains north of San Francisco sits the <a href="https://www.seti.org/ata">Allen Telescope Array</a>, the first radio telescope built from the ground up specifically for SETI use.</p>
<p>This unique facility is another exciting project, able to search for signals every day of the year. This project is currently upgrading the hardware and software on the original dish, including the ability to target several stars at once. This is a part of the non-profit research organisation, the SETI Institute.</p>
<h2>Space lasers!</h2>
<p>The SETI Institute is also looking for signals that would be best explained as “space lasers”.</p>
<p>Some astronomers hypothesise that intelligent beings might use massive lasers to communicate or even to propel spacecraft. This is because even here on Earth we’re investigating <a href="https://www.nasa.gov/feature/goddard/2022/the-future-of-laser-communications/">laser communication</a> and laser-propelled <a href="https://www.insidescience.org/news/new-light-sail-design-would-use-laser-beam-ride-space">light sails</a>.</p>
<p>To search for these mysterious flashes in the night sky, we need speciality instruments in locations around the globe, which are currently being developed and deployed. This is a research area I’m excited to watch progress and eagerly await results. </p>
<p>As of writing this article, sadly no alien laser signals have been found yet.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/do-aliens-exist-we-asked-five-experts-161811">Do aliens exist? We asked five experts</a>
</strong>
</em>
</p>
<hr>
<h2>Out there, somewhere</h2>
<p>It’s always interesting to ponder who or what might be living out in the Universe, but there is one problem we must overcome to meet or communicate with aliens. It’s the speed of light.</p>
<p>Everything we rely on to communicate via space requires light, and it can only travel so fast. This is where my optimism for finding intelligent life begins to fade. The Universe is big – <em>really</em> big.</p>
<p>To put it in perspective, humans started using radio waves to communicate across large distances in 1901. That <a href="https://ethw.org/Milestones:Reception_of_Transatlantic_Radio_Signals,_1901">first transatlantic signal</a> has only travelled 122 light years, reaching just 0.0000015% of the stars in our Milky Way.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An image of a spiral galaxy with a box on the lower right corner centred on a tiny blue dot" src="https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/505680/original/file-20230121-16-884k8k.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">The little blue dot in the centre of the square is the current extent of human broadcasts just in our own galaxy.</span>
<span class="attribution"><a class="source" href="https://www.planetary.org/space-images/extent-of-human-radio-broadcasts">Adam Grossman/Nick Risinger</a></span>
</figcaption>
</figure>
<p>Did your optimism just fade too? That is okay, because here is the wonderful thing… we don’t have to find life to know it is out there, somewhere.</p>
<p>When we consider the <a href="https://theconversation.com/how-many-stars-are-there-in-space-165370">trillions of galaxies</a>, septillion of stars, and likely many more planets just in the observable Universe, it feels near impossible that we are alone.</p>
<p>We can’t fully constrain the parameters we need to estimate how many other lifeforms might be out there, as famously proposed by Frank Drake, but using our best estimates and <a href="https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/numerical-testbed-for-hypotheses-of-extraterrestrial-life-and-intelligence/0C97E7803EEB69323C3728F02BA31AFA">simulations</a> the current best answer to this is tens of thousands of possible civilisations out there. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/frank-drake-has-passed-away-but-his-equation-for-alien-intelligence-is-more-important-than-ever-189935">Frank Drake has passed away but his equation for alien intelligence is more important than ever</a>
</strong>
</em>
</p>
<hr>
<p>The Universe <a href="https://theconversation.com/is-space-infinite-we-asked-5-experts-165742">might even be infinite</a>, but that is too much for my brain to comprehend on a weekday.</p>
<h2>Don’t forget the tiny aliens</h2>
<p>So, despite keenly listening for signals, we might not find intelligent life in our lifetimes. But there is hope for aliens yet.</p>
<p>The ones hiding in plain sight, on the planetary bodies of our Solar System. In the coming decades we’ll explore the moons of Jupiter and Saturn like never before, with missions hunting to find traces of basic life.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/505682/original/file-20230121-23485-sxmcy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/505682/original/file-20230121-23485-sxmcy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/505682/original/file-20230121-23485-sxmcy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/505682/original/file-20230121-23485-sxmcy9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/505682/original/file-20230121-23485-sxmcy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/505682/original/file-20230121-23485-sxmcy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/505682/original/file-20230121-23485-sxmcy9.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">Jupiter and the icy moon Europa. Concept art of the Europa Clipper mission currently under development.</span>
<span class="attribution"><span class="source">NASA/JPL</span></span>
</figcaption>
</figure>
<p>Mars will continue to be explored – eventually by humans – which could allow us to uncover and retrieve samples from new and unexplored regions.</p>
<p>Even if our future aliens are only tiny microbes, it would still be nice to know we have company in this Universe.</p>
<hr>
<p><em>Correction: this article has been amended to clarify that Julia and Yuri Milner are no longer Russian citizens.</em></p><img src="https://counter.theconversation.com/content/197621/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sara Webb 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>To date, we have not heard from any aliens. Nor have we seen any – but here are the fascinating projects working to change that.Sara Webb, Postdoctoral Research Fellow, Centre for Astrophysics and Supercomputing, Swinburne University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1986942023-02-01T12:08:35Z2023-02-01T12:08:35ZSeti: alien hunters get a boost as AI helps identify promising signals from space<figure><img src="https://images.theconversation.com/files/507097/original/file-20230130-12-qfen8v.jpg?ixlib=rb-1.1.0&rect=672%2C272%2C2956%2C1999&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The new study analysed data gathered at the Green Bank Observatory in West Virginia.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/green-bank-west-virginia-october-15-762059119">Shutterstock</a></span></figcaption></figure><p>An international team of researchers looking for signs of intelligent life in space have used artificial intelligence (AI) to reveal eight promising radio signals in data collected at a US observatory.</p>
<p>The results of their research, <a href="https://www.nature.com/articles/s41550-022-01872-z">published in Nature Astronomy</a> are remarkable. The team hasn’t yet carried out an exhaustive analysis, but the paper suggests the signals have many of the characteristics we would expect if they were artificially generated. In other words, they are the kinds of signals we might pick up from an extraterrestrial civilisation broadcasting into space.</p>
<p>A cursory review of the new paper suggest these are indeed promising signals. They’re much more compelling than what is perhaps the most famous Seti candidate, <a href="https://astronomy.com/news/2020/09/the-wow-signal-an-alien-missed-connectio">the “Wow!” signal</a>, radio emission bearing the hallmarks of an extraterrestrial origin that was collected by an Ohio telescope in 1977.</p>
<p>Realistically, it’s most likely that these eight new signals were generated by human technology. But the real story here is the effectiveness of AI and <a href="https://en.wikipedia.org/wiki/Deep_learning">the techniques used by the team to</a> dig out rare and interesting signals previously buried in the noise of human-generated <a href="https://public.nrao.edu/telescopes/radio-frequency-interference/">radio frequency interference,</a> such as mobile phones and GPS.</p>
<p>Astronomers working in the field of <a href="https://www.seti.org/primer-seti-seti-institute">Seti (the search for extraterrestrial intelligence)</a> must filter out interference produced by radio communications here on Earth.</p>
<p>In this case, Peter Ma from the University of Toronto and his colleagues unleashed a set of algorithms on a mountain of data collected by the <a href="https://greenbankobservatory.org">Green Bank Telescope in West Virginia</a>, US. The data was gathered through a Seti initiative called <a href="https://seti.berkeley.edu/listen/">Breakthrough Listen</a>, established in 2015 by the investor Yuri Milner and his wife Julia. </p>
<p>Here are the characteristics astronomers look for in signals that could be artificially-generated: firstly they are <a href="https://en.wikipedia.org/wiki/Narrowband">narrow-band</a>, which means that where the radio transmission is confined to only a few frequency channels. They also disappear as the telescope is moved to another direction in the sky, and they exhibit <a href="https://en.wikipedia.org/wiki/Doppler_effect">“Doppler drifting”</a>, where the frequency of the signal changes in a predictable way with time. We would expect Doppler drifting because both the transmitter — on a distant planet, for example — and the receiver, on Earth, are moving.</p>
<figure class="align-center ">
<img alt="Artist's impression of exoplanets" src="https://images.theconversation.com/files/507060/original/file-20230130-22-kadncw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507060/original/file-20230130-22-kadncw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=449&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507060/original/file-20230130-22-kadncw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=449&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507060/original/file-20230130-22-kadncw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=449&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507060/original/file-20230130-22-kadncw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507060/original/file-20230130-22-kadncw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507060/original/file-20230130-22-kadncw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Any artificial signals from deep space need to be distinguished from radio interference here on Earth.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/planets-deep-space-cosmos-nebula-stars-2057080619">Shutterstock</a></span>
</figcaption>
</figure>
<h2>Buried in the noise</h2>
<p>The Breakthrough Listen project’s <a href="https://seti.berkeley.edu/blc1/">first candidate signal</a>, called BLC1, was first announced in 2020. But it was <a href="https://www.nature.com/articles/s41550-021-01508-8">later traced</a> to transmissions associated with cheap electronic devices on this planet. The application of AI techniques to the Breakthrough Listen observing programme, however, is a potential game changer for the field. Even seasoned Seti researchers are beginning to think that we might be on the cusp of a momentous scientific breakthrough.</p>
<p>This may explain renewed interest by groups around the world that are planning for Seti success. For example, a <a href="https://seti.wp.st-andrews.ac.uk">Seti post-detection hub</a> has been set up at the University of St Andrews in Scotland. This will study how humans should react if we discover we are not alone in the Universe.</p>
<p>The International Academy of Astronautics (IAA) <a href="https://iaaseti.org/en/">Seti permanent committee</a> oversees the <a href="https://iaaseti.org/en/protocols/">Seti post-detection protocols</a>, which outline what steps scientists should take in the event of detecting a genuine signal. The IAA has opted to update the text of the protocols sometime later this year.</p>
<p>But the new study highlights a problem with previous signals of interest. When the team took another look at the stars associated with the eight narrow-band transmissions, they could no longer detect the signals. </p>
<p>It would not be surprising if many, and perhaps the vast majority of bona-fide Seti signals, were isolated events. After all, what are the chances that we point our telescopes in exactly the right direction, at the right time and with the right frequency on multiple occasions?</p>
<h2>Missing ingredients</h2>
<p>As I <a href="https://theconversation.com/seti-new-signal-excites-alien-hunters-heres-how-we-could-find-out-if-its-real-152498">argued here</a> a few years ago, Seti surveys would greatly benefit from employing multiple radio telescopes, operating in a manner that’s known as a <a href="https://public.nrao.edu/ask/how-does-a-radio-interferometer-work/">classical interferometer network</a>. </p>
<p>These telescope arrays (groups of several antennas observing together) generate huge amounts of data. With AI onboard, the challenge is perhaps more manageable than previously thought. </p>
<p>Breakthrough Listen is already using telescope arrays such as <a href="https://www.sarao.ac.za/science/meerkat/about-meerkat/">MeerKAT in South Africa</a> for Seti searches. In Europe, researchers have been experimenting with <a href="https://www.evlbi.org">arrays that span the globe</a>.</p>
<p>This European approach would help us isolate signals from human-made interference, give us multiple independent detections of individual events, and permit us to localise signals to individual stars and possibly orbiting planets. </p>
<p>Among the future projects is the <a href="https://www.skao.int/en">Square Kilometre Array</a>, an international project to build the two largest telescope arrays in the world, which will be based in Australia and South Africa. Another upcoming project is the <a href="https://ngvla.nrao.edu">next generation VLA (ngVLA)</a>, a series of linked telescope facilities that will be spread across the United States. These radio telescope arrays will be even more sensitive than current instruments.</p>
<p>It’s my belief — and indeed hope — that somewhere out there intelligent beings are waiting to be discovered. The AI revolution might be the missing ingredient that previous endeavours have lacked. In particular, AI algorithms will eventually evolve into powerful tools that no longer suffer from <a href="https://www.nist.gov/news-events/news/2022/03/theres-more-ai-bias-biased-data-nist-report-highlights">human biases</a>. </p>
<p>Lord Martin Rees, chairman of the Breakthrough Listen advisory board and the astronomer royal, has proposed that if we do find aliens they are likely to be <a href="https://theconversation.com/seti-why-extraterrestrial-intelligence-is-more-likely-to-be-artificial-than-biological-169966">intelligent machines</a> operating in the depths of space, unconstrained by the biological limitations placed on humans. </p>
<p>If we ever do find a bona-fide signal, it could just be that it’s mediated by machines on Earth and in space.</p><img src="https://counter.theconversation.com/content/198694/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Garrett is on the advisory board of the Breakthrough Listen initiative and the Seti Institute.</span></em></p>Can artificial intelligence transform the search for alien intelligence?Michael Garrett, Sir Bernard Lovell chair of Astrophysics and Director of Jodrell Bank Centre for Astrophysics, University of ManchesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1949292022-11-21T15:54:25Z2022-11-21T15:54:25ZHow to test if we’re living in a computer simulation<figure><img src="https://images.theconversation.com/files/496450/original/file-20221121-25-963m2s.png?ixlib=rb-1.1.0&rect=0%2C137%2C2000%2C1607&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">NASA, ESA, CSA, STScI</span></span></figcaption></figure><p>Physicists have long struggled to explain why the universe started out with conditions <a href="https://plato.stanford.edu/entries/fine-tuning/">suitable for life to evolve</a>. Why do the physical laws and constants <a href="https://theconversation.com/can-the-laws-of-physics-disprove-god-146638">take the very specific values</a> that allow stars, planets and ultimately life to develop? The expansive force of the universe, dark energy, for example, is much weaker than theory suggests it should be – allowing matter to clump together rather than being ripped apart.</p>
<p>A common answer is that we live in an infinite multiverse of universes, so we shouldn’t be surprised that at least one universe has turned out as ours. But another is that our universe is a computer simulation, with someone (perhaps an advanced alien species) fine-tuning the conditions.</p>
<p>The latter option is supported by a branch of science called <a href="https://arxiv.org/abs/1009.5161">information physics</a>, which suggests that space-time and matter are not fundamental phenomena. Instead, the physical reality is fundamentally made up of bits of information, from which our experience of space-time emerges. By comparison, temperature “emerges” from the collective movement of atoms. No single atom fundamentally has temperature. </p>
<p>This leads to the extraordinary possibility that our entire universe might in fact be a computer simulation. The idea is not that new. In 1989, the legendary physicist, <a href="https://phy.princeton.edu/department/history/faculty-history/john-wheeler">John Archibald Wheeler</a>, suggested that the universe is fundamentally mathematical and it can be seen as emerging from information. He coined the famous aphorism “<a href="https://plus.maths.org/content/it-bit">it from bit</a>”. </p>
<p>In 2003, philosopher <a href="https://nickbostrom.com/">Nick Bostrom</a> from Oxford University in the UK formulated his <a href="https://philpapers.org/rec/BOSAWL">simulation hypothesis</a>. This argues that it is actually highly probable that we live in a simulation. That’s because an advanced civilisation should reach a point where their technology is so sophisticated that simulations would be indistinguishable from reality, and the participants would not be aware that they were in a simulation.</p>
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<p>Physicist <a href="https://meche.mit.edu/people/faculty/SLLOYD@MIT.EDU">Seth Lloyd</a> from the Massachusetts Institute of Technology in the US took the simulation hypothesis to the next level by suggesting that the entire universe <a href="https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.88.237901">could be a giant quantum computer</a>.<br>
And in 2016, business magnate Elon Musk concluded “We’re most likely in a simulation” (see video above).</p>
<h2>Empirical evidence</h2>
<p>There is some evidence suggesting that our physical reality could be a simulated virtual reality rather than an objective world that exists independently of the observer.</p>
<p>Any virtual reality world will be based on information processing. That means everything is ultimately digitised or pixelated down to a minimum size that cannot be subdivided further: bits. This appears to mimic our reality according to the theory of quantum mechanics, which rules the world of atoms and particles. It states there is a <a href="https://www.symmetrymagazine.org/article/the-planck-scale">smallest, discrete unit</a> of energy, length and time. Similarly, <a href="https://theconversation.com/explainer-what-are-fundamental-particles-38339">elementary particles</a>, which make up all the visible matter in the universe, are the smallest units of matter. To put it simply, our world is pixelated.</p>
<p>The laws of physics that govern everything in the universe also resemble computer code lines that a simulation would follow in the execution of the program. Moreover, mathematical equations, numbers and geometric patterns <a href="https://theconversation.com/mathematics-is-beautiful-no-really-72921">are present everywhere</a> – the world appears to be entirely mathematical. </p>
<p>Another curiosity in physics supporting the simulation hypothesis is the maximum speed limit in our universe, which is the speed of light. In a virtual reality, this limit would correspond to the speed limit of the processor, or the processing power limit. We know that an overloaded processor slows down computer processing in a simulation. Similarly, Albert Einstein’s <a href="https://theconversation.com/how-einsteins-general-theory-of-relativity-killed-off-common-sense-physics-50042">theory of general relativity</a> shows that time slows in the vicinity of a black hole.</p>
<p>Perhaps the most supportive evidence of the simulation hypothesis comes from quantum mechanics. This suggest nature isn’t “real”: particles in determined states, such as specific locations, <a href="https://theconversation.com/four-common-misconceptions-about-quantum-physics-192062">don’t seem to exist</a> unless you actually observe or measure them. Instead, they are in a mix of different states simultaneously. Similarly, virtual reality needs an observer or programmer for things to happen. </p>
<p>Quantum “entanglement” also allows two particles to be spookily connected so that if you manipulate one, you automatically and immediately also manipulate the other, no matter how far apart they are – with the effect being seemingly faster than the speed of light, which should be impossible.</p>
<p>This could, however, also be explained by the fact that within a virtual reality code, all “locations” (points) should be roughly equally far from a central processor. So while we may think two particles are millions of light years apart, they wouldn’t be if they were created in a simulation.</p>
<h2>Possible experiments</h2>
<p>Assuming that the universe is indeed a simulation, then what sort of experiments could we deploy from within the simulation to prove this?</p>
<p>It is reasonable to assume that a simulated universe would contain a lot of information bits everywhere around us. These information bits represent the code itself. Hence, detecting these information bits will prove the simulation hypothesis. The recently proposed <a href="https://doi.org/10.1063/1.5123794">mass-energy-information (M/E/I) equivalence principle</a> – suggesting mass can be expressed as energy or information, or vice versa – states that information bits must have a small mass. This gives us something to search for.</p>
<p>I have postulated that information is in fact a fifth form of matter in the universe. I’ve even <a href="https://doi.org/10.1063/5.0064475">calculated the expected information content</a> per elementary particle. These studies led to the publication, in 2022, of <a href="https://doi.org/10.1063/5.0087175">an experimental protocol</a> to test these predictions. The experiment involves erasing the information contained inside elementary particles by letting them and their antiparticles (all particles have “anti” versions of themselves which are identical but have opposite charge) annihilate in a flash of energy – emitting “photons”, or light particles.</p>
<p>I have predicted the exact range of expected frequencies of the resulting photons based on information physics. The experiment is highly achievable with our existing tools, and we <a href="https://www.indiegogo.com/projects/is-the-universe-a-simulation-let-s-test-it--2#/">have launched a crowdfunding site</a>) to achieve it. </p>
<p>There are other approaches too. The late physicist <a href="https://royalsociety.org/people/john-barrow-11044/">John Barrow</a> has argued that a simulation would build up minor computational errors which the programmer would need to fix in order to keep it going. He suggested we might <a href="https://www.simulation-argument.com/barrowsim.pdf">experience such fixing</a> as contradictory experimental results appearing suddenly, such as the constants of nature changing. So monitoring the values of these constants is another option.</p>
<p>The nature of our reality is one of the greatest mysteries out there. The more we take the simulation hypothesis seriously, the greater the chances we may one day prove or disprove it.</p><img src="https://counter.theconversation.com/content/194929/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Melvin M. Vopson 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 may be ways to check if our universe is just simulated entertainment for an advanced, alien species.Melvin M. Vopson, Senior Lecturer in Physics, University of PortsmouthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1910542022-10-21T12:38:07Z2022-10-21T12:38:07ZSignatures of alien technology could be how humanity first finds extraterrestrial life<figure><img src="https://images.theconversation.com/files/490943/original/file-20221020-21-mv2tjy.jpg?ixlib=rb-1.1.0&rect=80%2C477%2C3753%2C1678&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Astronomers have been looking for radio waves sent by a distant civilization for more than 60 years.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/illustration-of-signal-coming-out-the-deep-cosmos-royalty-free-image/1338115983?phrase=signal%20coming%20from%20planet%20space&adppopup=true">Rytis Bernotas/iStock via Getty Images</a></span></figcaption></figure><p>If an alien were to look at Earth, many human technologies – from cell towers to fluorescent light bulbs – could be a beacon signifying the presence of life. </p>
<p><a href="https://sites.psu.edu/macyhuston/">We are</a> two <a href="https://sites.psu.edu/astrowright">astronomers</a> <a href="https://scholar.google.com/citations?user=lEUxaaIAAAAJ&hl=en&oi=ao">who</a> work on the <a href="https://www.pseti.psu.edu/about/">search for extraterrestrial intelligence</a> – or SETI. In our research, we try to characterize and detect signs of technology originating from beyond Earth. These are called technosignatures. While scanning the sky for a TV broadcast of some extraterrestrial Olympics may sound straightforward, searching for signs of distant, advanced civilizations is a much more nuanced and difficult task than it might seem.</p>
<h2>Saying ‘hello’ with radios and lasers</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A laser shooting up from an observatory into a starry sky." src="https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=902&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=902&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=902&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1133&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1133&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490923/original/file-20221020-1663-tvwgzj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1133&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 laser – like the one seen here – or beam of radio waves pointed intentionally at Earth would be a strong sign of extraterrestrial life.</span>
<span class="attribution"><a class="source" href="http://www.eso.org/public/images/gerd_huedepohl_4/">G. Hüdepohl/ESO</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The modern scientific <a href="https://astrobites.org/2021/08/16/classic-paper-summary/">search for extraterrestrial intelligence began in 1959</a> when astronomers Giuseppe Cocconi and Philip Morrison showed that radio transmissions from Earth <a href="https://doi.org/10.4159/harvard.9780674366688.c9">could be detected</a> by radio telescopes at interstellar distances. The same year, <a href="https://theconversation.com/frank-drake-has-passed-away-but-his-equation-for-alien-intelligence-is-more-important-than-ever-189935">Frank Drake</a>, launched the first SETI search, <a href="https://www.seti.org/project-ozma">Project Ozma</a>, by pointing a large radio telescope at two nearby Sun-like stars to see if he could detect any radio signals coming from them. Following the invention of the laser in 1960, astronomers showed that visible light could also <a href="https://doi.org/10.1038/190205a0">be detected from distant planets</a>.</p>
<p>These first, foundational attempts to detect <a href="http://www.bigear.org/oldseti.htm">radio</a> or <a href="https://doi.org/110.1086/423300">laser</a> signals from another civilization were all looking for focused, powerful signals that would have been intentionally sent to the solar system and meant to be found. </p>
<p>Given the technological limitations of the 1960s, astronomers did not give serious thought to searching for broadcast signals – like television and radio broadcasts on Earth – that would leak into space. But a beam of a radio signal, with all of its power focused towards Earth, could be detectable from much farther away – just picture the difference between a laser and a weak light bulb.</p>
<p>The search for intentional radio and laser signals is still one of the most popular SETI strategies today. However, this approach <a href="https://www.universetoday.com/149513/beyond-fermis-paradox-xvii-what-is-the-seti-paradox-hypothesis/">assumes that extraterrestrial civilizations want to communicate</a> with other technologically advanced life. Humans very rarely send targeted signals into space, and some scholars argue that intelligent species may <a href="https://theconversation.com/blasting-out-earths-location-with-the-hope-of-reaching-aliens-is-a-controversial-idea-two-teams-of-scientists-are-doing-it-anyway-182036">purposefully avoid broadcasting out their locations</a>. This search for signals that no one may be sending is called <a href="https://doi.org/10.48550/arXiv.physics/0611283">the SETI Paradox</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An aerial view of a desert with a huge number of satellite dishes." src="https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=328&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=328&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=328&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=412&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=412&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490932/original/file-20221020-1690-8mwnqz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=412&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 artist’s impression shows the Square Kilometer Array, a telescope array currently being built in both Australia and Africa that will be sensitive enough to detect the equivalent of radio broadcasts from distant planets.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:SKA_overview.jpg#/media/File:SKA_overview.jpg">SPDO/TDP/DRAO/Swinburne Astronomy Productions/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Leaking radio waves</h2>
<p>Though humans don’t transmit many intentional signals out to the cosmos, many technologies people use today produce a lot of radio transmissions that leak into space. Some of these signals would be detectable if they came from a nearby star.</p>
<p>The worldwide network of television towers constantly emits signals in many directions that leak into space and can <a href="https://doi.org/10.1126/science.199.4327.377">accumulate into a detectable, though relatively faint</a>, radio signal. Research is ongoing as to whether current emissions from cell towers in the radio frequency on Earth would be detectable using today’s telescopes, but the upcoming <a href="https://doi.org/10.1088/1475-7516/2007/01/020">Square Kilometer Array radio telescope will be able to detect</a> even fainter radio signals with <a href="https://theconversation.com/the-science-behind-the-square-kilometre-array-40870">50 times the sensitivity of current radio telescope arrays</a>. </p>
<p>Not all human-made signals are so unfocused, though. Astronomers and space agencies use beams of radio waves to communicate with <a href="https://www.nasa.gov/directorates/heo/scan/services/networks/deep_space_network/about">satellites and space craft</a> in the solar system. Some researchers also use radio waves for <a href="https://www.nasa.gov/feature/jpl/planetary-radar-observes-1000th-near-earth-asteroid-since-1968">radar to study asteroids</a>. In both of these cases, the radio signals are more focused and pointed out into space. Any extraterrestrial civilization that happened to be in the line of sight of these beams could likely detect these unambiguously artificial signals.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A rendering of a massive set of rings around a star in space." src="https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490926/original/file-20221020-18-l76626.png?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">A Dyson Sphere is a theoretical megastructure that would surround a star and collect its light to use as energy.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/kevinmgill/29401385502/">Kevin Gill/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Finding megastructures</h2>
<p>Aside from finding an actual alien spacecraft, radio waves are the most common technosignatures featured in sci-fi movies and books. But they are not the only signals that could be out there.</p>
<p>In 1960, astronomer Freeman Dyson theorized that, since stars are by far the most powerful energy source in any planetary system, a technologically advanced civilization might <a href="https://doi.org/10.1088/10.1126/science.131.3414.1667">collect a significant portion of the star’s light as energy</a> with what would essentially be a massive solar panel. Many astronomers call these megastructures, and there are a few ways to detect them.</p>
<p>After using the energy in the captured light, the technology of an advanced society would <a href="https://stem.guide/topic/entropy-the-second-law-of-thermodynamics/">re-emit some of the energy as heat</a>. Astronomers have shown that this heat <a href="https://ui.adsabs.harvard.edu/abs/1966ApJ...144.1216S/abstract">could be detectable</a> as extra infrared radiation coming from a star system.</p>
<p>Another possible way to find a megastructure would be to <a href="https://theconversation.com/what-are-the-odds-of-an-alien-megastructure-blocking-light-from-a-distant-star-49311">measure its dimming effect on a star</a>. Specifically, large artificial satellites orbiting a star would periodically block some of its light. This would appear as dips in the star’s apparent brightness over time. Astronomers could detect this effect similarly to how <a href="https://theconversation.com/are-there-any-planets-outside-of-our-solar-system-164062">distant planets are discovered today</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An artist's depiction of a planet covered in cities and with a chemically altered atmosphere." src="https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=495&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=495&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=495&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=622&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=622&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490924/original/file-20221020-13-90h06v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=622&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Advanced civilizations may produce a lot of pollution in the form of chemicals, light and heat that can be detected across the vast distances of space.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/press-release/goddard/2021/technosignature">NASA/Jay Freidlander</a></span>
</figcaption>
</figure>
<h2>A whole lot of pollution</h2>
<p>Another technosignature that astronomers have thought about is pollution.</p>
<p>Chemical pollutants – like <a href="https://www.nasa.gov/press-release/goddard/2021/technosignature">nitrogen dioxide</a> and <a href="https://doi.org/10.3847/PSJ/ac5404">chlorofluorocarbons</a> on Earth are almost exclusively produced by human industry. It is possible to detect these molecules in the <a href="https://theconversation.com/its-all-in-the-atmosphere-exploring-planets-orbiting-distant-stars-62034">atmospheres of exoplanets</a> with the same method the James Webb Space Telescope is using to <a href="https://theconversation.com/to-search-for-alien-life-astronomers-will-look-for-clues-in-the-atmospheres-of-distant-planets-and-the-james-webb-space-telescope-just-proved-its-possible-to-do-so-184828">search distant planets for signs of biology</a>. If astronomers find a planet with an atmosphere filled with chemicals that can only be produced by technology, it may be a sign of life.</p>
<p>Finally, <a href="https://doi.org/10.1093/mnras/stac469">artificial light</a> or <a href="https://doi.org/10.1017/S1473550414000585">heat from cities and industry</a> could also be detectable with large optical and infrared telescopes, as would a large <a href="https://doi.org/10.3847/1538-4357/aaae66">number of satellites orbiting a planet</a>. But a civilization would need to produce far more heat, light and satellites than Earth does to be detectable across the vastness of space using technology humans currently possess.</p>
<h2>Which signal is best?</h2>
<p>No astronomer has ever found a confirmed technosignature, so it’s hard to say what will be the first sign of alien civilizations. While many astronomers have thought a lot about <a href="https://doi.org/10.1017/S1473550419000284">what might make for a good signal</a>,
ultimately, nobody knows what extraterrestrial technology might look like and what signals are out there in the Universe. </p>
<p>Some astronomers support a <a href="https://www.aspbooks.org/publications/213/519.pdf">generalized SETI</a> approach which searches for anything in space that current scientific knowledge cannot naturally explain. Some, like us, continue to search for both intentional and unintentional technosignatures. The bottom line is that there are many avenues for detecting distant life. Since no one knows what approach is likely to succeed first, there is still a lot of exciting work left to do.</p><img src="https://counter.theconversation.com/content/191054/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jason Wright does research supported by the Penn State Extraterrestrial Intelligence Center. He also does SETI research and runs conferences dedicated to SETI with funds from NASA and the NSF.</span></em></p><p class="fine-print"><em><span>Macy Huston does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The technology of an advanced alien civilization is likely to produce many signs that could be detected across the vastness of space. Two astronomers explain the search for technosignatures.Macy Huston, PhD Candidate in Astronomy and Astrophysics, Penn StateJason Wright, Professor of Astronomy and Astrophysics, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1904962022-09-19T12:21:17Z2022-09-19T12:21:17ZSuper-Earths are bigger, more common and more habitable than Earth itself – and astronomers are discovering more of the billions they think are out there<figure><img src="https://images.theconversation.com/files/484712/original/file-20220914-4859-4nvzdu.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3892%2C2125&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Astronomers think the most likely place to find life in the galaxy is on super-Earths, like Kepler-69c, seen in this artist's rendering.</span> <span class="attribution"><a class="source" href="http://www.nasa.gov/mission_pages/kepler/multimedia/images/kepler-69c.html">NASA Ames/JPL-CalTech</a></span></figcaption></figure><p>Astronomers now routinely discover <a href="https://exoplanets.nasa.gov/">planets orbiting stars outside of the solar system</a> – they’re called exoplanets. But in summer 2022, teams working on NASA’s <a href="https://www.nasa.gov/tess-transiting-exoplanet-survey-satellite">Transiting Exoplanet Survey Satellite</a> found a few particularly interesting planets orbiting in the habitable zones of their parent stars.</p>
<p>One planet is <a href="https://www.npr.org/2022/09/07/1121465588/new-planet-super-earth-life-nasa">30% larger than Earth</a> and orbits its star in less than three days. The other is <a href="https://exoplanets.nasa.gov/news/1710/discovery-alert-intriguing-new-super-earth-could-get-a-closer-look/">70% larger than the Earth</a> and might host a deep ocean. These two exoplanets are <a href="https://exoplanets.nasa.gov/what-is-an-exoplanet/planet-types/super-earth/">super-Earths</a> – more massive than the Earth but smaller than ice giants like Uranus and Neptune.</p>
<p>I’m a <a href="https://scholar.google.com/citations?user=OrRLRQ4AAAAJ&hl=en">professor of astronomy</a> who studies galactic cores, distant galaxies, <a href="https://www.cambridge.org/core/books/living-cosmos/11D69005D09D25581AE4E6684EC8A3C1">astrobiology</a> and <a href="https://mitpress.mit.edu/9780262047661/worlds-without-end/">exoplanets</a>. I closely follow the search for planets that might host life.</p>
<p>Earth is still the only place in the universe scientists know to be home to life. It would seem logical to focus the search for life on Earth clones – <a href="https://www.space.com/30172-six-most-earth-like-alien-planets.html">planets with properties close to Earth’s</a>. But research has shown that the best chance astronomers have of finding life on another planet is likely to be on a super-Earth similar to the ones found recently.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An image showing Earth and Neptune with a middle sized planet in between." src="https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=277&fit=crop&dpr=1 600w, https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=277&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=277&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=348&fit=crop&dpr=1 754w, https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=348&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/484702/original/file-20220914-13-irjlj2.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=348&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 super-Earth is any rocky planet that is bigger than Earth and smaller than Neptune.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Exoplanet_Comparison_CoRoT-7_b.png#/media/File:Exoplanet_Comparison_CoRoT-7_b.png">Aldaron</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Common and easy to find</h2>
<p>Most super-Earths orbit cool dwarf stars, which are lower in mass and live much longer than the Sun. There are hundreds of cool dwarf stars for every star like the Sun, and scientists have found super-Earths orbiting <a href="http://www.inaf.it/en/inaf-news/billions-of-rocky-planets-in-the-habitable-zones-around-red-dwarfs">40% of cool dwarfs</a> they have looked at. Using that number, astronomers estimate that there are <a href="http://www.inaf.it/en/inaf-news/billions-of-rocky-planets-in-the-habitable-zones-around-red-dwarfs">tens of billions</a> of super-Earths in habitable zones where liquid water can exist in the Milky Way alone. Since all life on Earth uses water, water is thought to be critical for habitability.</p>
<p>Based on current projections, about a <a href="https://exoplanets.nasa.gov/what-is-an-exoplanet/planet-types/super-earth/">third of all exoplanets</a> are super-Earths, making them the most common type of exoplanet in the Milky Way. The nearest is only <a href="https://exoplanets.nasa.gov/news/1533/discovery-alert-a-new-super-earth-in-the-neighborhood-six-light-years-away/">six light-years away</a> from Earth. You might even say that our solar system is unusual since it does not have a planet with a mass between that of Earth and Neptune.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing how a planet passing in front of a star can dim the light." src="https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=187&fit=crop&dpr=1 600w, https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=187&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=187&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=235&fit=crop&dpr=1 754w, https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=235&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/484708/original/file-20220914-16744-zlu3u9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=235&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Most exoplanets are discovered by looking for how they dim the light coming from their parent stars, so bigger planets are easier to find.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Planetary_transit.svg#/media/File:Planetary_transit.svg">Nikola Smolenski</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Another reason super-Earths are ideal targets in the search for life is that they’re much easier to <a href="https://sci.esa.int/web/exoplanets/-/60655-detection-methods">detect and study</a> than Earth-sized planets. There are two methods astronomers use to detect exoplanets. One looks for the gravitational effect of a planet on its parent star and the other looks for brief dimming of a star’s light as the planet passes in front of it. Both of these detection methods are easier with a bigger planet.</p>
<h2>Super-Earths are super habitable</h2>
<p>Over 300 years ago, German philosopher Gottfried Wilhelm Leibniz argued that Earth was the “<a href="https://www.gutenberg.org/files/17147/17147-h/17147-h.htm">best of all possible worlds</a>.” Leibniz’s argument was meant to address the question of why evil exists, but modern astrobiologists have explored a similar question by asking what makes a planet hospitable to life. It turns out that Earth is not the best of all possible worlds.</p>
<p>Due to Earth’s tectonic activity and changes in the brightness of the Sun, the climate has veered over time from ocean-boiling hot to planetwide, deep-freeze cold. Earth has been uninhabitable for humans and other larger creatures for most of its 4.5-billion-year history. Simulations suggest the long-term <a href="http://dx.doi.org/10.1038/s43247-020-00057-8">habitability of Earth was not inevitable</a>, but was a matter of chance. Humans are literally lucky to be alive.</p>
<p>Researchers have come up with a <a href="https://doi.org/10.1089/ast.2013.1088">list of the attributes</a> that make a planet very conducive to life. Larger planets are more likely to be geologically active, a feature that scientists think would <a href="https://www.geoscienze.unipd.it/influence-plate-tectonics-life-evolution-and-biodiversity-biogeodynamical-modeling">promote biological evolution</a>. So the most habitable planet would have roughly twice the mass of the Earth and be between 20% and 30% larger by volume. It would also have oceans that are shallow enough for light to stimulate life all the way to the seafloor and an average temperature of 77 degrees Fahrenheit (25 degrees Celsius). It would have an atmosphere thicker than the Earth’s that would act as an insulating blanket. Finally, such a planet would orbit a star older than the Sun to give life longer to develop, and it would have a strong magnetic field that <a href="https://www.eurekalert.org/news-releases/939605">protects against cosmic radiation</a>. Scientists think that these attributes combined will make a planet super habitable.</p>
<p>By definition, super-Earths have many of the attributes of a super habitable planet. To date, astronomers have discovered <a href="https://doi.org/10.1089/ast.2019.2161">two dozen super-Earth exoplanets</a> that are, if not the best of all possible worlds, theoretically more habitable than Earth.</p>
<p>Recently, there’s been an exciting addition to the inventory of habitable planets. Astronomers have <a href="https://doi.org/10.48550/arXiv.2009.12377">started discovering exoplanets</a> that have been <a href="https://www.eso.org/public/news/eso2120/">ejected from their star systems</a>, and there could be <a href="https://www.eso.org/public/news/eso2120/">billions of them</a> roaming the Milky Way. If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could <a href="https://universemagazine.com/en/life-on-super-earths-can-exist-for-84-billion-years/">sustain life for tens of billions of years</a>, far longer than life on Earth could persist before the Sun dies.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A watery world in front of a dim star." src="https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=328&fit=crop&dpr=1 600w, https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=328&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=328&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=412&fit=crop&dpr=1 754w, https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=412&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/484711/original/file-20220914-4859-utbv87.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=412&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">One of the newly discovered super-Earths, TOI-1452b, might be covered in a deep ocean and could be conducive to life.</span>
<span class="attribution"><a class="source" href="http://www.exoplanetes.umontreal.ca/an-extrasolar-world-covered-in-water/?lang=en">Benoit Gougeon, Université de Montréal</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Detecting life on super-Earths</h2>
<p>To detect life on distant exoplanets, astronomers will look for biosignatures, <a href="https://theconversation.com/to-search-for-alien-life-astronomers-will-look-for-clues-in-the-atmospheres-of-distant-planets-and-the-james-webb-space-telescope-just-proved-its-possible-to-do-so-184828">byproducts of biology</a> that are detectable in a planet’s atmosphere. </p>
<p>NASA’s James Webb Space Telescope was designed before astronomers had discovered exoplanets, so the telescope is not optimized for exoplanet research. But it is able to do some of this science and is scheduled to <a href="https://webbtelescope.org/contents/news-releases/2022/news-2022-017#section-id-2">target two potentially habitable super-Earths</a> in its first year of operations. Another set of super-Earths with massive oceans discovered in the past few years, as well as the planets discovered this summer, are also <a href="https://doi.org/10.3847/1538-4357/abfd9c">compelling targets for James Webb</a>. </p>
<p>But the best chances for finding signs of life in exoplanet atmospheres will come with the next generation of giant, ground-based telescopes: the <a href="https://elt.eso.org/science/exoplanets/#atmospheres">39-meter Extremely Large Telescope</a>, the <a href="https://www.tmt.org/">Thirty Meter Telescope</a> and the <a href="https://giantmagellan.org/">25.4-meter Giant Magellan Telescope</a>. These telescopes are all under construction and set to start collecting data by the end of the decade.</p>
<p>Astronomers know that the ingredients for life are out there, but habitable does not mean inhabited. Until researchers find evidence of life elsewhere, it’s possible that life on Earth was a unique accident. While there are many reasons why a habitable world <a href="https://doi.org/10.1098%2Frsta.2013.0082">would not have signs of life</a>, if, over the coming years, astronomers look at these super habitable super-Earths and find nothing, humanity may be forced to conclude that the universe is a lonely place.</p>
<p><em>Editor’s Note: The story has been updated to correct the size of the Giant Magellan Telescope.</em></p><img src="https://counter.theconversation.com/content/190496/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>Newly discovered super-Earths add to the list of planets around other stars that offer the best chance of finding life. An astronomer explains what makes these super-Earths such excellent candidates.Chris Impey, University Distinguished Professor of Astronomy, University of ArizonaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1848282022-07-14T12:34:04Z2022-07-14T12:34:04ZTo search for alien life, astronomers will look for clues in the atmospheres of distant planets – and the James Webb Space Telescope just proved it’s possible to do so<figure><img src="https://images.theconversation.com/files/473980/original/file-20220713-20-g1f04j.png?ixlib=rb-1.1.0&rect=34%2C116%2C691%2C572&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">TRAPPIST-1e is a rocky exoplanet in the habitable zone of a star 40 light-years from Earth and may have water and clouds, as depicted in this artist's impression.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:TRAPPIST-1e_artist_impression_2018.png#/media/File:TRAPPIST-1e_artist_impression_2018.png">NASA/JPL-Caltech/Wikimedia Commons</a></span></figcaption></figure><p>The ingredients for life are <a href="https://doi.org/10.1073/pnas.98.3.805">spread throughout the universe</a>. While Earth is the only known place in the universe with life, detecting life beyond Earth is a <a href="https://www.planetary.org/articles/the-2020-astrophysics-decadal-survey-guide">major goal</a> of <a href="https://www.planetary.org/space-policy/what-is-the-decadal-survey">modern astronomy</a> and <a href="https://www.planetary.org/space-policy/what-is-the-decadal-survey">planetary science</a>.</p>
<p>We are two scientists who study <a href="https://scholar.google.com/citations?user=2SCIYjIAAAAJ&hl=en&oi=ao">exoplanets</a> and <a href="https://scholar.google.com/citations?user=OrRLRQ4AAAAJ&hl=en&oi=ao">astrobiology</a>. Thanks in large part to next-generation telescopes like James Webb, researchers like us will soon be able to measure the chemical makeup of atmospheres of planets around other stars. The hope is that one or more of these planets will have a chemical signature of life.</p>
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<a href="https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing green bands around stars." src="https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473981/original/file-20220713-24-ei1562.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">There are many known exoplanets in habitable zones – orbits not too close to a star that the water boils off but not so far that the planet is frozen solid – as marked in green for both the solar system and Kepler-186 star system with its planets labeled b, c, d, e and f.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Kepler186f-ComparisonGraphic-20140417_improved.jpg#/media/File:Kepler186f-ComparisonGraphic-20140417_improved.jpg">NASA Ames/SETI Institute/JPL-Caltech/Wikimedia Commons</a></span>
</figcaption>
</figure>
<h2>Habitable exoplanets</h2>
<p>Life <a href="https://doi.org/10.1073/pnas.1816535115">might exist in the solar system</a> where there is liquid water – like the subsurface aquifers on Mars or in the oceans of Jupiter’s moon Europa. However, searching for life in these places is incredibly difficult, as they are hard to reach and detecting life would require sending a probe to return physical samples.</p>
<p>Many astronomers believe there’s a <a href="https://exoplanets.nasa.gov/news/1675/life-in-the-universe-what-are-the-odds/">good chance that life exists on planets orbiting other stars</a>, and it’s possible that’s where <a href="https://doi.org/10.1016/j.actaastro.2022.03.019">life will first be found</a>.</p>
<p>Theoretical calculations suggest that there are around <a href="https://www.technologyreview.com/2020/11/06/1011784/half-milky-way-sun-like-stars-home-earth-like-planets-kepler-gaia-habitable-life/">300 million potentially habitable planets</a> in the Milky Way galaxy alone and <a href="https://doi.org/10.3847/1538-3881/abc418">several habitable Earth-sized planets</a> within only 30 light-years of Earth – essentially humanity’s galactic neighbors. So far, astronomers have <a href="https://exoplanets.nasa.gov/">discovered over 5,000 exoplanets</a>, including hundreds of potentially habitable ones, using <a href="https://sci.esa.int/web/exoplanets/-/60655-detection-methods">indirect methods</a> that measure how a planet affects its nearby star. These measurements can give astronomers information on the mass and size of an exoplanet, but not much else.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A chart showing two lines each with two peaks in the blue and red wavelengths." src="https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473983/original/file-20220713-17654-sd7qoy.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">Every material absorbs certain wavelengths of light, as shown in this diagram depicting the wavelengths of light absorbed most easily by different types of chlorophyll.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Chlorophyll_ab_spectra-en.svg#/media/File:Chlorophyll_ab_spectra-en.svg">Daniele Pugliesi/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Looking for biosignatures</h2>
<p>To detect life on a distant planet, astrobiologists will study starlight that has <a href="https://doi.org/10.1089/ast.2017.1729">interacted with a planet’s surface or atmosphere</a>. If the atmosphere or surface was transformed by life, the light may carry a clue, called a “biosignature.”</p>
<p>For the first half of its existence, Earth sported an atmosphere without oxygen, even though it hosted simple, single-celled life. Earth’s biosignature was very faint during this early era. That changed abruptly <a href="https://asm.org/Articles/2022/February/The-Great-Oxidation-Event-How-Cyanobacteria-Change">2.4 billion years ago</a> when a new family of algae evolved. The algae used a process of photosynthesis that produces free oxygen – oxygen that isn’t chemically bonded to any other element. From that time on, Earth’s oxygen-filled atmosphere has left a strong and easily detectable biosignature on light that passes through it.</p>
<p>When light bounces off the surface of a material or passes through a gas, certain wavelengths of the light are more likely to remain trapped in the gas or material’s surface than others. This selective trapping of wavelengths of light is why objects are different colors. Leaves are green because chlorophyll is particularly good at absorbing light in the red and blue wavelengths. As light hits a leaf, the red and blue wavelengths are absorbed, leaving mostly green light to bounce back into your eyes.</p>
<p>The pattern of missing light is determined by the specific composition of the material the light interacts with. Because of this, astronomers can learn something about the composition of an exoplanet’s atmosphere or surface by, in essence, measuring the specific color of light that comes from a planet. </p>
<p>This method can be used to recognize the presence of certain atmospheric gases that are associated with life – such as oxygen or methane – because these gasses leave very specific signatures in light. It could also be used to detect peculiar colors on the surface of a planet. On Earth, for example, the chlorophyll and other pigments plants and algae use for photosynthesis capture specific wavelengths of light. These pigments <a href="https://doi.org/10.1073/pnas.1304213111">produce characteristic colors</a> that can be detected by using a sensitive infrared camera. If you were to see this color reflecting off the surface of a distant planet, it would potentially signify the presence of chlorophyll.</p>
<h2>Telescopes in space and on Earth</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A giant gold mirror in a lab." src="https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=899&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=899&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=899&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473985/original/file-20220713-17654-d5rtyi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&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 James Webb Space Telescope is the first telescope able to detect chemical signatures from exoplanets, but it is limited in its capabilities.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:JWST_Full_Mirror.jpg#/media/File:JWST_Full_Mirror.jpg">NASA/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>It takes an incredibly powerful telescope to detect these subtle changes to the light coming from a potentially habitable exoplanet. For now, the only telescope capable of such a feat is the new <a href="http://jwst.nasa.gov/">James Webb Space Telescope</a>. As it <a href="https://blogs.nasa.gov/webb/2022/07/11/nasas-webb-telescope-is-now-fully-ready-for-science/">began science operations</a> in July 2022, James Webb took a reading of the spectrum of the <a href="https://www.nytimes.com/2022/07/12/science/wasp-96b-exoplanet-webb-telescope.html">gas giant exoplanet WASP-96b</a>. The spectrum showed the presence of water and clouds, but a planet as large and hot as WASP-96b is unlikely to host life.</p>
<p>However, this early data shows that James Webb is capable of detecting faint chemical signatures in light coming from exoplanets. In the coming months, Webb is set to turn its mirrors toward <a href="https://www.space.com/42512-trappist-1-planet-could-host-life.html">TRAPPIST-1e</a>, a potentially habitable Earth-sized planet a mere 39 light-years from Earth.</p>
<p>Webb can look for biosignatures by studying planets as they pass in front of their host stars and capturing <a href="https://www.physics.uu.se/research/astronomy-and-space-physics/research/planets/exoplanet-atmospheres/">starlight that filters through the planet’s atmosphere</a>. But Webb was not designed to search for life, so the telescope is only able to scrutinize a few of the nearest potentially habitable worlds. It also can only detect changes to <a href="https://doi.org/10.3847/1538-3881/ab21e0">atmospheric levels of carbon dioxide, methane and water vapor</a>. While certain combinations of these gasses <a href="https://doi.org/10.1038/s41550-021-01579-7">may suggest life</a>, Webb is not able to detect the presence of unbonded oxygen, which is the strongest signal for life.</p>
<p>Leading concepts for future, even more powerful, space telescopes include plans to block the bright light of a planet’s host star to reveal starlight reflected back from the planet. This idea is similar to using your hand to block sunlight to better see something in the distance. Future space telescopes could use small, internal masks or large, external, umbrella-like spacecraft to do this. Once the starlight is blocked, it becomes much easier to study light bouncing off a planet.</p>
<p>There are also three enormous, ground-based telescopes currently under construction that will be able to search for biosignatures: the <a href="http://gmto.org/">Giant Magellen Telescope</a>, the <a href="https://www.tmt.org/">Thirty Meter Telescope</a> and the <a href="https://www.eso.org/sci/facilities/eelt/">European Extremely Large Telescope</a>. Each is far more powerful than existing telescopes on Earth, and despite the handicap of Earth’s atmosphere distorting starlight, these telescopes might be able to probe the atmospheres of the closest worlds for oxygen.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A cow and its calf standing in a field." src="https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=406&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=406&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=406&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=511&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=511&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473982/original/file-20220713-12-4xssot.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=511&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Animals, including cows, produce methane, but so do many geologic processes.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Cows_eating_grass_(42882305160).jpg#/media/File:Cows_eating_grass_(42882305160).jpg">Jernej Furman/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Is it biology or geology?</h2>
<p>Even using the most powerful telescopes of the coming decades, astrobiologists will only be able to detect strong biosignatures produced by worlds that have been completely transformed by life.</p>
<p>Unfortunately, most gases released by terrestrial life can also be produced by nonbiological processes – cows and volcanoes both release methane. Photosynthesis produces oxygen, but sunlight does, too, when it splits water molecules into oxygen and hydrogen. There is a <a href="https://doi.org/10.1089/ast.2017.1727">good chance astronomers will detect some false positives</a> when looking for distant life. To help rule out false positives, astronomers will need to understand a planet of interest well enough to understand whether its <a href="https://doi.org/10.1089/ast.2017.1737">geologic or atmospheric processes could mimic a biosignature</a>. </p>
<p>The next generation of exoplanet studies has the potential to pass the bar of the <a href="https://quoteinvestigator.com/2021/12/05/extraordinary/">extraordinary evidence</a> needed to prove the existence of life. The first data release from the James Webb Space Telescope gives us a sense of the exciting progress that’s coming soon.</p><img src="https://counter.theconversation.com/content/184828/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><p class="fine-print"><em><span>Daniel Apai receives funding from NASA and the Gordon and Betty Moore Foundation.</span></em></p>Life on Earth has dramatically changed the chemistry of the planet. Astronomers will measure light that bounces off distant planets to look for similar clues that they host life.Chris Impey, University Distinguished Professor of Astronomy, University of ArizonaDaniel Apai, Professor of Astronomy and Planetary Sciences, University of ArizonaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1851652022-06-16T04:37:39Z2022-06-16T04:37:39ZDid a giant radio telescope in China just discover aliens? Not so FAST…<blockquote>
<p>“Extraordinary claims require extraordinary evidence.”<br>
– <cite>Carl Sagan (Cosmos, 1980)</cite></p>
</blockquote>
<p>This phrase is the <a href="https://en.wikipedia.org/wiki/Sagan_standard">standard</a> that astronomers will be applying to a curious signal captured with China’s “Sky Eye” telescope that <em>might</em> be a transmission from alien technology. </p>
<p>An article reporting the signal was posted on the website of China’s state-backed Science and Technology Daily newspaper, <a href="https://www.bloomberg.com/news/articles/2022-06-15/china-says-it-may-have-detected-signals-from-alien-civilizations">but was later removed.</a> So have astronomers finally found evidence of intelligent found life beyond Earth? And is it being hushed up?</p>
<p>We should be intrigued, but not too excited (yet). An interesting signal has to go through a lot of tests to check whether it truly carries the signature of extraterrestrial technology or is just the result of an unexpected source of terrestrial interference. </p>
<p>And as for the deletion: media releases are normally timed for simultaneous release with peer-reviewed results – which are not yet available – so it was likely just released a bit early by mistake. </p>
<h2>An eye on the sky</h2>
<p>Sky Eye, which is offically known as the <a href="https://en.wikipedia.org/wiki/Five-hundred-meter_Aperture_Spherical_Telescope">Five-hundred-meter Aperture Spherical Telescope (FAST)</a>, is the the largest and most sensitive single-dish radio telescope in the world. A engineering marvel, its gargantuan structure is built inside a natural basin in the mountains of <a href="https://goo.gl/maps/wd25oAxVWSV9Ddnf8">Guizhou, China</a>. </p>
<p>The telescope is so huge it can’t be physically tilted, but it can be pointed in a direction by thousands of actuators that deform the telescope’s reflective surface. By deforming the surface, the location of the telescope’s focal point changes, and the telescope can look at a different part of the sky.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/china-completes-worlds-largest-radio-telescope-raising-hopes-of-finding-new-worlds-and-alien-life-62237">China completes world's largest radio telescope – raising hopes of finding new worlds and alien life</a>
</strong>
</em>
</p>
<hr>
<p>FAST detects radiation at radio wavelengths (up to 10 cm) and is used for astronomical research in a wide range of areas. One area is the search for extraterrestrial intelligence, or SETI. </p>
<p>SETI observations are mainly done in “piggy-back” mode, which means they are taken while the telescope is also running its primary science programs. In this way, large swaths of the sky can be scanned for signs of alien technology – or “technosignatures” – without getting in the way of other science operations. For special targets like nearby exoplanets, dedicated SETI observations are still carried out.</p>
<h2>The hunt for alien technology</h2>
<p>Technosignature searches have been ongoing since the 1960s, when the American astronomer <a href="https://en.wikipedia.org/wiki/Frank_Drake">Frank Drake</a> pointed the <a href="https://public.nrao.edu/telescopes/tatel/">26-metre Tatel telescope</a> toward two nearby Sun-like stars and scanned them for signs of technology. </p>
<p>Over the years, technosignature searches have become far more rigorous and sensitive. The systems in place at FAST are also able to process billions of times more of the radio spectrum than Drake’s experiment. </p>
<p>Despite these advances, we haven’t yet found any evidence of life beyond Earth.</p>
<p>FAST sifts through enormous amounts of data. The telescope feeds 38 billion samples a second into a cluster of high-performance computers, which then produces exquisitely detailed charts of incoming radio signals. These charts are then searched for signals that look like technosignatures. </p>
<p>With such a large collecting area, FAST can pick up incredibly faint signals. It is about 20 times more sensitive than Australia’s Murriyang telescope at the Parkes Radio Observatory. FAST could easily detect a transmitter on a nearby exoplanet with a similar output power to radar systems we have here on Earth. </p>
<h2>The trouble with sensitivity</h2>
<p>The trouble with being so sensitive is that you can uncover radio interference that would otherwise be too faint to detect. We SETI researchers have had this problem before. </p>
<p>Last year, using Murriyang, we detected an extremely interesting signal we called <a href="https://theconversation.com/a-mysterious-signal-looked-like-a-sign-of-alien-technology-but-it-turned-out-to-be-radio-interference-170548">BLC1</a>. </p>
<p>However, it turned out to be very strange interference (not aliens). To uncover its true nature, we had to develop a <a href="https://seti.berkeley.edu/blc1/flowchart.html">new verification framework</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Technosignature verification flowchart" src="https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469059/original/file-20220615-3512-8jqevi.png?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">A flowchart for verifying candidate technosignatures, developed for BLC1.</span>
<span class="attribution"><span class="source">Sofia Sheikh (SETI Institute)</span></span>
</figcaption>
</figure>
<p>With BLC1, it took about a year from when it was initially reported to when peer-reviewed analysis was published. Similarly, we may need to wait a while for the FAST signal to be analysed in depth. </p>
<p>Professor Zhang Tongjie, chief scientist for the China Extraterrestrial Civilization Research Group, acknowledged this in the Science & Technology Daily report: </p>
<blockquote>
<p>The possibility that the suspicious signal is some kind of radio interference is also very high, and it needs to be further confirmed and ruled out. This may be a long process.</p>
</blockquote>
<p>And we may need to get used to a gap between finding candidate signals and verifying them. FAST and other telescopes are likely to find many more signals of interest. </p>
<p>Most of these will turn out to be interference, but some may be new astrophysical phenomena, and some may be <em>bona fide</em> technosignatures.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-mysterious-signal-looked-like-a-sign-of-alien-technology-but-it-turned-out-to-be-radio-interference-170548">A mysterious signal looked like a sign of alien technology — but it turned out to be radio interference</a>
</strong>
</em>
</p>
<hr>
<h2>Stay intrigued</h2>
<p>Will FAST’s extraordinary signals meet the burden of extraordinary evidence? Until their work is reviewed and published, it’s still too early to say, but it’s encouraging that their SETI search algorithms are finding curious signals. </p>
<p>Between FAST, the <a href="https://breakthroughinitiatives.org/initiative/1">Breakthrough Listen</a> initiative, and the SETI Institute’s <a href="https://www.seti.org/press-release/cosmic-all-antennas-very-large-array-ready-stream-data-technosignature-research">COSMIC</a> program, the SETI field is seeing a lot of interest and activity. And it’s not just radio waves: searches are also underway using <a href="https://oirlab.ucsd.edu/PANOSETI.html">optical and infrared light</a>. </p>
<p>As for right now: stay intrigued, but don’t get too excited.</p><img src="https://counter.theconversation.com/content/185165/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Danny C Price is Australian Project Scientist for the Breakthrough Listen initiative.</span></em></p>Have astronomers finally found evidence of intelligent found life beyond Earth?Danny C Price, Senior research fellow, Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1775132022-05-25T13:46:19Z2022-05-25T13:46:19ZWhat the Voyager space probes can teach humanity about immortality and legacy as they sail through space for trillions of years<figure><img src="https://images.theconversation.com/files/464877/original/file-20220523-11-z3t5y6.jpg?ixlib=rb-1.1.0&rect=0%2C9%2C799%2C589&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Scientists expect the Voyager spacecraft to outlive Earth by at least a trillion years.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:PIA17036_Voyager_the_Explorer.jpg#/media/File:PIA17036_Voyager_the_Explorer.jpg">NASA/JPL-CalTech</a></span></figcaption></figure><p>Voyager 1 is the farthest human-made object from Earth. After sweeping by Jupiter, Saturn, Uranus and Neptune, it is now almost <a href="https://voyager.jpl.nasa.gov/mission/status/">15 billion miles (24 billion kilometers) from Earth</a> in interstellar space. Both Voyager 1 and its twin, Voyager 2, carry little pieces of humanity in the form of their <a href="https://voyager.jpl.nasa.gov/golden-record/">Golden Records</a>. These messages in a bottle include spoken greetings in 55 languages, sounds and images from nature, an album of recordings and images from numerous cultures, and a written message of welcome from Jimmy Carter, who was U.S. president <a href="https://theconversation.com/voyager-golden-records-40-years-later-real-audience-was-always-here-on-earth-79886">when the spacecraft left Earth in 1977</a>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A golden colored record with 'The Sounds of Earth' written in the center." src="https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464881/original/file-20220523-23-zyjgnu.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">Each Voyager spacecraft carries a Golden Record containing two hours of sounds, music and greetings from around the world. Carl Sagan and other scientists assumed that any civilization advanced enough to detect and capture the record in space could figure out how to play it.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:The_Sounds_of_Earth_-_GPN-2000-001976.jpg">NASA/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>The Golden Records were built to last a billion years in the environment of space, but in a recent analysis of the paths and perils these explorers may face, astronomers calculated that they <a href="https://www.space.com/predicting-voyager-golden-records-distant-future">could exist for trillions of years</a> without coming remotely close to any stars.</p>
<p>Having spent my career in the field of <a href="https://sipa.fiu.edu/people/faculty/religious-studies/hurchingson.james.html">religion and science</a>, I’ve thought a lot about how spiritual ideas intersect with technological achievements. The incredible longevity of the Voyager spacecraft presents a uniquely tangible entry point into exploring ideas of immortality.</p>
<p>For many people, immortality is the everlasting existence of a soul or spirit that follows death. It can also mean the continuation of one’s legacy in memory and records. With its Golden Record, each Voyager provides such a legacy, but only if it is discovered and appreciated by an alien civilization in the distant future. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="People in black standing around a coffin at a gravesite." src="https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464879/original/file-20220523-15-ck32f0.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"></a>
<figcaption>
<span class="caption">Many religions espouse some form of life after death.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/outdoor-shot-of-funeral-royalty-free-image/104305070?adppopup=true">RubberBall Productions/Brand X Pictures via Getty Images</a></span>
</figcaption>
</figure>
<h2>Life after death</h2>
<p>Religious beliefs about immortality are numerous and diverse. Most religions foresee a postmortem career for a personal soul or spirit, and these range from everlasting residence among the stars to reincarnation. </p>
<p>The ideal eternal life for many Christians and Muslims is to abide forever in God’s presence in heaven or paradise. Judaism’s teachings about what happens after death are less clear. In the Hebrew Bible, the dead are mere “shades” in a darkened place called Sheol. Some rabbinical authorities <a href="https://jewishencyclopedia.com/articles/12697-resurrection">give credence to the resurrection of the righteous</a> and even to the eternal status of souls.</p>
<p>Immortality is not limited to the individual. It can be collective as well. For many Jews, the <a href="https://library.yctorah.org/2016/05/the-importance-of-the-land-of-israel/">final destiny of the nation of Israel or its people</a> is of paramount importance. Many Christians anticipate a <a href="https://www.britannica.com/topic/Kingdom-of-God">future general resurrection</a> of all who have died and the coming of the kingdom of God for the faithful.</p>
<p>Jimmy Carter, whose message and autograph are immortalized in the Golden Records, is a progressive Southern Baptist and a living example of religious hope for immortality. Now <a href="https://healthcare.utah.edu/healthfeed/postings/2015/08/082015_jimmy.carter.php">battling brain cancer</a> and approaching centenarian status, he has thought about dying. Following his diagnosis, Carter <a href="https://www.washingtonpost.com/politics/2019/11/04/jimmy-carter-says-he-is-completely-ease-with-death/">concluded in a sermon</a>: “It didn’t matter to me whether I died or lived. … My Christian faith includes complete confidence in life after death. So I’m going to live again after I die.”</p>
<p>It is plausible to conclude that the potential of an alien witnessing the Golden Record and becoming aware of Carter’s identity billions of years in the future would offer only marginal additional consolation for him. Carter’s knowledge in his ultimate destiny is a measure of his deep faith in the immortality of his soul. In this sense, he likely represents people of numerous faiths. </p>
<h2>Secular immortality</h2>
<p>For people who are secular or nonreligious there is little solace to be found in an appeal to the continuing existence of a soul or spirit following one’s death. Carl Sagan, who came up with the idea for the Golden Records and led their development, wrote of the afterlife: “<a href="https://www.goodreads.com/quotes/1221453-i-would-love-to-believe-that-when-i-die-i">I know of nothing to suggest that it is more than just wishful thinking</a>.” He was more saddened by thoughts of missing important life experiences – like seeing his children grow up – than fearful about the expected annihilation of his conscious self with the death of his brain.</p>
<p>For those like Sagan there are other possible options for immortality. They include <a href="https://gizmodo.com/why-freezing-yourself-is-a-terrible-way-to-achieve-immo-1552142674">freezing and preserving the body for future physical resurrection</a> or <a href="https://www.wsj.com/articles/will-your-uploaded-mind-still-be-you-11568386410">uploading one’s consciousness and turning it into a digital form</a> that would long outlast the brain. Neither of these potential paths to physical immortality has proved to be feasible yet.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/cEzcFXRKHUw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The Golden Records contain a snapshot of Earth and humanity.</span></figcaption>
</figure>
<h2>The Voyagers and legacy</h2>
<p>Most people, whether secular or religious, want the actions they do while alive to bear <a href="https://doi.org/10.1016/j.jaging.2004.08.002">continuing meaning into the future as their fruitful legacy</a>. People want to be remembered and appreciated, even cherished. Sagan summed it up nicely: “To live in the hearts we leave behind <a href="https://www.goodreads.com/quotes/1029590-to-live-in-the-hearts-we-leave-behind-is-to">is to live forever</a>.” </p>
<p>With Voyagers 1 and 2 estimated to exist for more than a trillion years, they are about as immortal as it gets for human artifacts. Even before the Sun’s expected demise when it runs out of fuel in about 5 billion years, all living species, mountains, seas and forests <a href="https://theconversation.com/the-sun-wont-die-for-5-billion-years-so-why-do-humans-have-only-1-billion-years-left-on-earth-37379">will have long been obliterated</a>. It will be as if we and all the marvelous and extravagant beauty of planet Earth never existed – a devastating thought to me.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A chart showing the path of Voyager 1 spiraling off into the distance." src="https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=199&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=199&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=199&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=250&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=250&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464878/original/file-20220523-21-ofwph8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=250&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Voyager 1’s path, in white, has taken the craft well past the orbits of the outer planets into interstellar space, where aliens may someday come across the relic of humanity.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Voyager_1_skypath_1977-2030.png#/media/File:Voyager_1_skypath_1977-2030.png">NASA/JPL via Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>But in the distant future, the two Voyager spacecraft will still be floating in space, awaiting discovery by an advanced alien civilization for whom the messages on the Golden Records were intended. Only those records will likely remain as testimony and legacy of Earth, a kind of objective immortality.</p>
<p>Religious and spiritual people can find solace in the belief that God or an afterlife waits for them after death. For the secular, hoping that someone or something will remember humanity, any wakeful and appreciative aliens will have to do.</p><img src="https://counter.theconversation.com/content/177513/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Edward Huchingson does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A professor of religion and science explains different views on immortality, from the religious perspective of President Jimmy Carter to the scientific, secular take of Carl Sagan.James Edward Huchingson, Professor Emeritus and Lecturer in Religion and Science, Florida International UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1835622022-05-25T10:57:30Z2022-05-25T10:57:30ZA ‘doorway’ on Mars? How we see things in space that aren’t there<figure><img src="https://images.theconversation.com/files/464594/original/file-20220521-19-9cg9h2.jpeg?ixlib=rb-1.1.0&rect=65%2C34%2C1808%2C642&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A panorama stitched together from about 100 individual Curiosity images. The 'door' is circled, and is tiny and hard to see at this scale.</span> <span class="attribution"><a class="source" href="https://mars.nasa.gov/resources/26754/door-shaped-fracture-spotted-by-curiosity-at-east-cliffs/">NASA/JPL-Caltech/MSSS</a></span></figcaption></figure><p>Enthusiasts lit up social media recently with images of what appeared to be a “doorway” into a hillside on Mars. Was it, some wondered, evidence that the red planet could be, or have been, inhabited by aliens? The “door” was imaged by Nasa’s Curiosity rover on May 7 on the slopes of Mount Sharp, the central massif within Gale crater, where it landed in 2012. Described on one website as a “<a href="https://thinis.net/pharaonic-tomb-door-on-mars/">pharaonic tomb door</a>”, because of its resemblance to some ancient Egyptian remains, it is in fact only about one foot high.</p>
<p>It is hard to spot on the panoramic image mosaic of the hillside above, but it leaps out at the eye if you see the individual frame where it occurs, seen below. It does look like a doorway until you realise how small it is. And if you boost the contrast in the dark parts of the image, the picture just about reveals a solid rock face at the back of the shadowed interior. So as a gateway into the hollow hills of Mars, it doesn’t lead very far.</p>
<figure class="align-center ">
<img alt="Image of the 'door' in black and white." src="https://images.theconversation.com/files/464596/original/file-20220521-14810-plryu4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464596/original/file-20220521-14810-plryu4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=535&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464596/original/file-20220521-14810-plryu4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=535&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464596/original/file-20220521-14810-plryu4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=535&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464596/original/file-20220521-14810-plryu4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=672&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464596/original/file-20220521-14810-plryu4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=672&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464596/original/file-20220521-14810-plryu4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=672&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Raw Curiosity camera image centred on the ‘door’.</span>
<span class="attribution"><span class="source">Nasa/JPL-Caltech/MSSS</span></span>
</figcaption>
</figure>
<h2>What the “door” really is</h2>
<p>Nobody with even a little geological experience is likely to mistake the feature as a “door”. A geologist would note the thin and slightly sloping repeated layers of sandstone making up the whole of the rock face, and would immediately expect that they were looking at the eroded remains of hardened sand dunes. These once covered the stream and lake sediments that <a href="https://theconversation.com/rover-detects-ancient-organic-material-on-mars-and-it-could-be-trace-of-past-life-97755">Curiosity examined earlier</a> in its gradual climb up through the layers of sedimentary rock making up Mount Sharp.</p>
<p>A geologist would also spot the steep and fairly straight cracks running up the rock face, and recognise these as “joints”. These are fractures that typically open up when the weight of overlying rock layers is removed by erosion. There is a particularly obvious joint in the left of the “door” image, but several others can be made out – including one that forms the smooth wall that lines up with the left side of the “door” itself. There’s another joint that forms the right side of the feature.</p>
<figure class="align-center ">
<img alt="Black and white detail of the 'door' with red lines added to show joints." src="https://images.theconversation.com/files/464597/original/file-20220521-16-to6nmg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464597/original/file-20220521-16-to6nmg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=536&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464597/original/file-20220521-16-to6nmg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=536&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464597/original/file-20220521-16-to6nmg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=536&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464597/original/file-20220521-16-to6nmg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=673&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464597/original/file-20220521-16-to6nmg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=673&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464597/original/file-20220521-16-to6nmg.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">
<figcaption>
<span class="caption">The raw image with red lines added to show some of the joints.</span>
<span class="attribution"><span class="source">Nasa/JPL-Caltech/MSSS</span></span>
</figcaption>
</figure>
<p>The whole hillside has been eroded back. The “doorway” is simply a place where the wind has been able to scour out the poorly consolidated sand and dust from the rock face a little more effectively, in an area bounded by the joints on either side. The base of an overlying bed of sandstone is the “door lintel”, and the sloping top of a bed of sandstone forms the gentle ramp that leads up to the door.</p>
<h2>Artefacts on Mars</h2>
<p>It doesn’t take much searching on the internet to find images taken by Mars rovers that show rock formations that resemble other familiar objects, even though all are implausibly out of place. We should not be surprised that some of the innumerable rocks on Mars have weird shapes, because many have been sandblasted by wind erosion for billions of years. </p>
<figure class="align-center ">
<img alt="Image of a long stone among several others looks superficially like a thigh bone." src="https://images.theconversation.com/files/464759/original/file-20220523-18-k5bah8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464759/original/file-20220523-18-k5bah8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=536&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464759/original/file-20220523-18-k5bah8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=536&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464759/original/file-20220523-18-k5bah8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=536&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464759/original/file-20220523-18-k5bah8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=673&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464759/original/file-20220523-18-k5bah8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=673&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464759/original/file-20220523-18-k5bah8.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">
<figcaption>
<span class="caption">A bunch of stones scoured out by the wind on Mars. One in the middle looks like a thigh-bone from this angle.</span>
<span class="attribution"><span class="source">Nasa/JPL-Caltech/MSSS</span></span>
</figcaption>
</figure>
<p>Apart from “doors” and bits of “hardware” ranging from wrecked “spaceships” and a <a href="https://www.republicworld.com/technology-news/science/ufo-specialist-detects-ancient-alien-jet-engine-remains-on-mars.html">“jet engine”</a> to individual items of “cutlery”, images have also captured “pyramids”, numerous <a href="https://www.news.com.au/technology/science/archaeology/mars-female-warrior-statue-represents-everything-crazy-about-the-ancient-alien-crowd/news-story/de94bf2c89c04bb6b00cba0db966440e">“humanoid heads”</a>, “dinosaurs”, various “bones”, and even a <a href="https://gizmodo.com/the-weirdest-images-ever-taken-on-mars-1843445035">“squirrel”</a>. Only a few of these strange objects are real, and those are all junk that humans put there. The others lose their visual distinctiveness if seen at closer range or from a different perspective. </p>
<figure class="align-center ">
<img alt="Image of wreckage, deliberately crashed on Mars, seen from above." src="https://images.theconversation.com/files/464760/original/file-20220523-29403-smhn9r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464760/original/file-20220523-29403-smhn9r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=430&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464760/original/file-20220523-29403-smhn9r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=430&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464760/original/file-20220523-29403-smhn9r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=430&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464760/original/file-20220523-29403-smhn9r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=541&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464760/original/file-20220523-29403-smhn9r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=541&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464760/original/file-20220523-29403-smhn9r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=541&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A genuine alien artefact on Mars: the backshell of the Perseverance lander, jettisoned prior to landing.</span>
<span class="attribution"><span class="source">Nasa/JPL-Caltech</span></span>
</figcaption>
</figure>
<h2>Weirdness beyond Mars</h2>
<p>“Seeing” the familiar even when it isn’t there is a phenomenon called <a href="https://mars.nasa.gov/multimedia/space-oddities/">pareidolia</a>. This denotes what happens when you see faces in the random pattern of your wallpaper, or peering out from the <a href="https://www.mirror.co.uk/news/weird-news/woman-stitches-after-finding-face-27038975">grain of wooden flooring</a>, or in the clouds. The latter, for example, is what’s causing Jupiter to look angry in the image below. </p>
<figure class="align-center ">
<img alt="Image of a part of Jupiter, where the clouds look like an angry face." src="https://images.theconversation.com/files/464771/original/file-20220523-18-do8uey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464771/original/file-20220523-18-do8uey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464771/original/file-20220523-18-do8uey.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464771/original/file-20220523-18-do8uey.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464771/original/file-20220523-18-do8uey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464771/original/file-20220523-18-do8uey.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464771/original/file-20220523-18-do8uey.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">Jupiter looking angry, imaged by Nasa’s JunoCam on 19 May 2017.</span>
<span class="attribution"><span class="source">Nasa/JPL-Caltech/SwRI/MSSS/Jason Major</span></span>
</figcaption>
</figure>
<p>Seemingly mysterious objects don’t occur solely on Mars. In December 2021, <a href="https://theconversation.com/china-lands-on-the-far-side-of-moon-here-is-the-science-behind-the-mission-108566">China’s Chang'e 4 rover </a> – still doing great things on the on the lunar far side more than three years after landing – spotted a <a href="https://www.space.com/china-yutu-2-moon-rover-cube-shaped-object-photos">“hut shaped” object</a> 80 metres away. It duly trundled towards it, and revealed it to be just a boulder, presumably ejected from a nearby impact crater. Some say it looks like a crouching rabbit, but I doubt anyone is claiming that it was sculpted by aliens.</p>
<figure class="align-center ">
<img alt="Distant view by the Chang'e 4 rover showing the 'hut' like rock 80 m away, plus a close up view when it got there." src="https://images.theconversation.com/files/464787/original/file-20220523-43418-k5lek2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464787/original/file-20220523-43418-k5lek2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=374&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464787/original/file-20220523-43418-k5lek2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=374&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464787/original/file-20220523-43418-k5lek2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=374&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464787/original/file-20220523-43418-k5lek2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=470&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464787/original/file-20220523-43418-k5lek2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=470&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464787/original/file-20220523-43418-k5lek2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=470&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Distant view by the Chang'e 4 rover showing the hut-like rock 80m away, plus a close up view when it got there.</span>
<span class="attribution"><span class="source">CNSA/CLEP</span></span>
</figcaption>
</figure>
<p>One of the most famous, and largest, examples of pareidolia is the Horsehead Nebula. This is a vast cosmic cloud of gas and dust, within which whole stellar systems are forming. An image collected in the right part of the spectrum and with an appropriate exposure time shows a shape that most people would recognise as a horse’s head. Shift wavelengths (which we can do) or look at it from a different direction (which we can’t) and the recognisable shape will vanish.</p>
<figure class="align-center ">
<img alt="Image of a dark nebula in the shape of a horse's head" src="https://images.theconversation.com/files/464845/original/file-20220523-30932-px0mdh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/464845/original/file-20220523-30932-px0mdh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=616&fit=crop&dpr=1 600w, https://images.theconversation.com/files/464845/original/file-20220523-30932-px0mdh.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=616&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/464845/original/file-20220523-30932-px0mdh.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=616&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/464845/original/file-20220523-30932-px0mdh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=775&fit=crop&dpr=1 754w, https://images.theconversation.com/files/464845/original/file-20220523-30932-px0mdh.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=775&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/464845/original/file-20220523-30932-px0mdh.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=775&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Horsehead nebula in Orion, imaged in the visible part of the spectrum.</span>
<span class="attribution"><span class="source">ESO</span></span>
</figcaption>
</figure>
<p>Back on Earth, climbers high on <a href="https://www.stridingedge.net/walks/8308/">Great Gable</a>, a mountain in Cumbria, UK, often look out for Cat Rock, otherwise known as Sphinx Rock. Seen from below this looks like a sitting cat, and seen side-on it resembles the profile of the Sphinx’s head. So far as I know, everyone accepts this as fluke and no one claims it as evidence that aliens have left landscape clues to their visits to Earth. It beats me why people persist in making such claims for flukey rock formations on Mars.</p>
<p>Ultimately, although you can generally believe your eyes, you should be cautious in believing your brain’s interpretation of what your eyes see.</p>
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<strong>
Read more:
<a href="https://theconversation.com/perseverance-mars-rover-how-to-prove-whether-theres-life-on-the-red-planet-154982">Perseverance Mars rover: how to prove whether there’s life on the red planet</a>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/mushrooms-on-mars-five-unproven-claims-that-alien-life-exists-161366">Mushrooms on Mars? Five unproven claims that alien life exists</a>
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<img src="https://counter.theconversation.com/content/183562/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Rothery is Professor of Planetary Geosciences at the Open University. He is co-leader of the European Space Agency's Mercury Surface and Composition Working Group, and a Co-Investigator on MIXS (Mercury Imaging X-ray Spectrometer) that is now on its way to Mercury on board the European Space Agency's Mercury orbiter BepiColombo. He has received funding from the UK Space Agency and the Science & Technology Facilities Council for work related to Mercury and BepiColombo, and from the European Commission under its Horizon 2020 programme for work on planetary geological mapping (776276 Planmap). He is author of Planet Mercury - from Pale Pink Dot to Dynamic World (Springer, 2015), Moons: A Very Short Introduction (Oxford University Press, 2015) and Planets: A Very Short Introduction (Oxford University Press, 2010). He is Educator on the Open University's free learning Badged Open Course (BOC) on Moons and its equivalent FutureLearn Moons MOOC, and chair of the Open University's level 2 course on Planetary Science and the Search for Life.</span></em></p>We should not be surprised that some of the innumerable rocks on Mars have weird shapes, because many have been sand-blasted by wind erosion for billions of years.David Rothery, Professor of Planetary Geosciences, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1834432022-05-20T01:50:09Z2022-05-20T01:50:09ZIs there evidence aliens have visited Earth? Here’s what’s come out of US congress hearings on ‘unidentified aerial phenomena’<figure><img src="https://images.theconversation.com/files/464403/original/file-20220520-16-npefrs.jpeg?ixlib=rb-1.1.0&rect=134%2C208%2C8044%2C5248&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source"> JIM LO SCALZO/EPA</span></span></figcaption></figure><p>The United States Congress recently held a hearing into US government information <a href="https://www.congress.gov/event/117th-congress/house-event/114761?s=1&r=4">pertaining to</a> “unidentified aerial phenomena” (UAPs). </p>
<p>The last investigation of this kind happened more than 50 years ago, as part of a US Air Force investigation called <a href="https://catalog.archives.gov/id/597821">Project Blue Book</a>, which examined reported sightings of unidentified flying objects (note the change in name). </p>
<p>The current hearings are the result of a stipulation attached to a <a href="https://www.intelligence.senate.gov/publications/intelligence-authorization-act-fiscal-year-2021">2020 COVID-19 relief bill</a>, which required US Intelligence agencies to produce a report on UAPs within 180 days. That <a href="https://www.dni.gov/files/ODNI/documents/assessments/Prelimary-Assessment-UAP-20210625.pdf">report</a> appeared in June last year. </p>
<p>But why would governments be interested in UAPs? One exciting line of thought is UAPs are alien spacecraft visiting Earth. It’s a concept that gets a lot of attention, by playing on decades of sci-fi movies, views about what goes on in <a href="https://en.wikipedia.org/wiki/Area_51">Area 51</a>, and purported sightings by the public.</p>
<p>A much more prosaic line of thought is governments are interested in unexplained aerial phenomena – especially those within their own sovereign airspace – because they may represent technologies developed by an adversary. </p>
<p>Indeed, most discussion at the recent hearing revolved around potential threats from UAPs, on the basis they were such human-made technologies.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/rO_M0hLlJ-Q?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Footage of three UAPs from US Navy pilots.</span></figcaption>
</figure>
<p>None of the public testimony went any way towards supporting a conclusion that alien spacecraft have crashed on, or visited, Earth. The hearings did include closed classified sessions that presumably dealt with more sensitive security information.</p>
<p>There is no doubt unexplained phenomena have been observed, such as in footage obtained by navy pilots (above) showing fast moving airborne objects. But the leap to aliens requires far more substantial and direct evidence – incredible evidence – that can be widely scrutinised using the tools of science.</p>
<p>After all, the existence of life elsewhere in the universe is a fascinating question of science and society. So the <a href="https://en.wikipedia.org/wiki/Search_for_extraterrestrial_intelligence">search for extra-terrestrial life</a> is a legitimate pursuit, subject to the same burden of evidence that applies to all science.</p>
<h2>A drop in an ocean</h2>
<p>On and off over the past decade, I’ve used radio telescopes to perform wide ranging experiments to search <a href="https://arxiv.org/pdf/2009.03267.pdf">for technosignatures</a> – signs of technological civilisations on planets elsewhere in our galaxy (the Milky Way). But after decades of many teams of experts using powerful telescopes, we still haven’t covered much territory. </p>
<p>If the Milky Way is considered equivalent to the Earth’s oceans, the sum total of our decades of searching is like taking a random swimming pool worth of water out of the ocean to search for a shark. </p>
<p>On top of that, we’re not even sure sharks exist and, if they do, what they would look like or how they would behave. While I believe life will almost certainly exist among the trillions of planets in the universe – the sheer scale of the universe is a problem.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/do-aliens-exist-we-asked-five-experts-161811">Do aliens exist? We asked five experts</a>
</strong>
</em>
</p>
<hr>
<h2>What would it take to make contact?</h2>
<p>The vast volume of the universe makes it very difficult to achieve interstellar travel, receive signals, or communicate with any potential far-off lifeforms (at least according to the laws of physics as we know them).</p>
<p>Speeds are limited to the <a href="https://en.wikipedia.org/wiki/Speed_of_light">speed of light</a>, which is around 300,000 km per second. It’s pretty fast. But even at that speed it would take a signal roughly four years to travel between Earth and <a href="https://en.wikipedia.org/wiki/Alpha_Centauri">the nearest star</a> in our galaxy, which is four light years away.</p>
<p>But Einstein’s theory of special relativity tells us that, in practice, the speed of a physical object such as a spacecraft will be slower than the speed of light.</p>
<p>Also, thanks to the <a href="https://en.wikipedia.org/wiki/Inverse-square_law">inverse square law of radiation</a>, signals get weaker in proportion to the square of the distance they have travelled. Over interstellar distances, that’s a killer. </p>
<p>So for planets hundreds or thousands of light years away, travel times are likely in the many thousands of years. And any signals originating from civilisations on those planets are incredibly weak and difficult to detect.</p>
<h2>Cover ups?</h2>
<p>Could it be aliens <em>have</em> crashed on Earth and the US government is just covering it up, as Republican Congressman <a href="https://burchett.house.gov/">Tim Burchett</a> claimed in <a href="https://www.the-sun.com/news/5356929/us-wreckage-ufos-truth-congressman/">his reaction to the hearing</a>?</p>
<p>For airlines belonging to the International Air Transport Association, the chance of plane crash is about <a href="https://www.iata.org/en/pressroom/pr/2021-03-25-01/">one in a million</a>. That begs the question: do we think an alien spacecraft that can travel for thousands of years, across interstellar distances, is more robust and better designed than our planes? </p>
<p>Let’s say it’s a hundred times better. Which means the chance of a crash is one in a hundred million. So to end up with alien wreckage stashed away at Area 51, we would need one hundred million visits from alien spacecraft. That would be 2,739 visits from aliens per day, every day, for the past 100 years!</p>
<p>So, where are they? The near-Earth environment should be constantly buzzing with aliens.</p>
<p>With <a href="https://leolabs.space/?lang=en-au">radars constantly scanning space</a>, billions of mobile phone cameras, and hundreds of thousands of amateur astronomers photographing the sky (as well as professional astronomers with powerful telescopes), there should be a lot of really good evidence in the hands of the general public and scientists – not just governments.</p>
<p>It’s much more likely the UAPs presented in evidence are home-grown, or due to natural phenomena we don’t yet understand. </p>
<p>In science, <a href="https://en.wikipedia.org/wiki/Occam%27s_razor">Occam’s Razor</a> is still a great starting point; the best explanation is the simplest explanation consistent with the known facts. Until there is much more – and much, much better – evidence, let’s conclude aliens haven’t visited yet.</p>
<p>I can’t lie though, I’m hoping I’ll see a time when that evidence exists. Until then, I’ll keep searching the skies to do my bit.</p><img src="https://counter.theconversation.com/content/183443/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steven Tingay receives funding from Western Australian Government, Australian Government, and international funding agencies. He is a member of the Australian Labor Party.</span></em></p>What kind of evidence would we really need, before we could reasonably conclude alien contact had been made?Steven Tingay, John Curtin Distinguished Professor (Radio Astronomy), Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.