tag:theconversation.com,2011:/es/topics/satellites-4029/articlesSatellites – The Conversation2024-03-27T23:55:16Ztag:theconversation.com,2011:article/2267292024-03-27T23:55:16Z2024-03-27T23:55:16ZA cosmic ‘speed camera’ just revealed the staggering speed of neutron star jets in a world first<figure><img src="https://images.theconversation.com/files/584904/original/file-20240327-26-ntaiw6.jpg?ixlib=rb-1.1.0&rect=1283%2C180%2C5431%2C3798&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Nuclear explosions on a neutron star feed its jets.
</span> <span class="attribution"><span class="source">Danielle Futselaar and Nathalie Degenaar, Anton Pannekoek Institute, University of Amsterdam</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>How fast can a neutron star drive powerful jets into space? The answer, it turns out, is about one-third the speed of light, as our team has just revealed in a <a href="https://www.nature.com/articles/s41586-024-07133-5">new study</a> published in Nature.</p>
<p>Energetic cosmic beams known as <a href="https://www.britannica.com/science/radio-jet">jets</a> are seen throughout our universe. They are launched when material – mainly dust and gas – falls in towards any dense central object, such as a neutron star (an extremely dense remnant of a once-massive star) or a <a href="https://science.nasa.gov/universe/black-holes/">black hole</a>. </p>
<p>The jets carry away some of the gravitational energy released by the infalling gas, recycling it back into the surroundings on far larger scales.</p>
<p>The most powerful jets in the universe come from the biggest black holes at the centres of galaxies. The energy output of these jets can affect the evolution of an entire galaxy, or even a galaxy cluster. This makes jets a critical, yet intriguing, component of our universe.</p>
<p>Although jets are common, we still don’t fully understand how they are launched. Measuring the jets from a neutron star has now given us valuable information.</p>
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Read more:
<a href="https://theconversation.com/the-brightest-object-in-the-universe-is-a-black-hole-that-eats-a-star-a-day-222612">The brightest object in the universe is a black hole that eats a star a day</a>
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<h2>Jets from stellar corpses</h2>
<p>Jets from black holes tend to be bright, and have been well studied. However, the jets from neutron stars are typically much fainter, and much less is known about them.</p>
<p>This presents a problem, since we can learn a lot by comparing the jets launched by different celestial objects. <a href="https://imagine.gsfc.nasa.gov/science/objects/neutron_stars1.html">Neutron stars</a> are extremely dense stellar corpses – cosmic cinders the size of a city, yet containing the mass of a star. We can think of them as enormous atomic nuclei, each about 20 kilometres across.</p>
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<p>In contrast to black holes, neutron stars have both a solid surface and a magnetic field, and gas falling onto them releases less gravitational energy. All of these properties will have an effect on how their jets are launched, making studies of neutron star jets particularly valuable.</p>
<p>One key clue to how jets are launched comes from their speeds. If we can determine how jet speeds vary with the mass or spin of the neutron star, that would provide a powerful test of theoretical predictions. But it is extremely challenging to measure jet speeds accurately enough for such a test.</p>
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Read more:
<a href="https://theconversation.com/unexpected-find-from-a-neutron-star-forces-a-rethink-on-radio-jets-103843">Unexpected find from a neutron star forces a rethink on radio jets</a>
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<h2>A cosmic speed camera</h2>
<p>When we measure speeds on Earth, we time an object between two points. This could be a 100-metre sprinter running down the track, or a point-to-point speed camera tracking a car.</p>
<p>Our team, led by Thomas Russell from the <a href="http://www.inaf.it/en">Italian National Institute of Astrophysics</a> in Palermo, conducted a new experiment to do this for neutron star jets.</p>
<p>What has made this measurement so difficult in the past is that jets are steady flows. This means there is no single starting point for our timer. But we were able to identify a short-lived signal at X-ray wavelengths that we could use as our “starting gun”.</p>
<p>Being so dense, neutron stars can “steal” matter from a nearby orbiting companion star. While some of that gas is launched outwards as jets, most of it ends up falling onto the neutron star. As the material piles up, it gets hotter and denser.</p>
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<p>When enough material has built up, it triggers a thermonuclear explosion. A runaway nuclear fusion reaction occurs and rapidly spreads to engulf the entire star. The fusion lasts for a few seconds to minutes, causing a short-lived <a href="https://www.nasa.gov/universe/nasas-nicer-catches-record-setting-x-ray-burst/">burst of X-rays</a>.</p>
<h2>One step closer to solving a mystery</h2>
<p>We thought this thermonuclear explosion would disrupt the neutron star’s jets. So, we used CSIRO’s <a href="https://www.csiro.au/en/about/facilities-collections/atnf/australia-telescope-compact-array">Australia Telescope Compact Array</a> to stare at the jets for three days at radio wavelengths to try and catch the disruption. At the same time, we used the European Space Agency’s <a href="https://www.esa.int/Science_Exploration/Space_Science/Integral_overview">Integral</a> telescope to look at the X-rays from the system.</p>
<p>To our surprise, we found the jets got brighter after every pulse of X-rays. Instead of disrupting the jets, the thermonuclear explosions seemed to power them up. And this pattern was repeated ten times in one neutron star system, and then again in a second system.</p>
<p>We can explain this surprising result if the X-ray pulse causes gas swirling around the neutron star to fall inwards more quickly. This, in turn, provides more energy and material to divert into the jets.</p>
<p>Most importantly, however, we can use the X-ray burst to indicate the launch time of the jets. We timed how long they took to move outwards to where they became visible at two different radio wavelengths. These start and finish points provided us with our cosmic speed camera.</p>
<p>Interestingly, the jet speed we measured was close to the “escape speed” from a neutron star. On Earth, this escape speed is <a href="https://www.britannica.com/science/escape-velocity">11.2 kilometres per second</a> – what rockets need to achieve to break free of Earth’s gravity. For a neutron star, that value is around half the speed of light.</p>
<p>Our work has introduced a new technique for measuring neutron star jet speeds. Our next steps will be to see how the jet speed changes for neutron stars with different masses and rotation rates. That will allow us to directly test theoretical models, taking us one step closer to figuring out how such powerful cosmic jets are launched.</p><img src="https://counter.theconversation.com/content/226729/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>James Miller-Jones receives funding from the Australian Research Council and the Western Australian State Government.</span></em></p>Powerful jets are launched from the most massive objects in our universe, but we don’t fully understand how. This measurement gets us a step closer to solving the mystery.James Miller-Jones, Professor, Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2266212024-03-27T01:49:55Z2024-03-27T01:49:55ZAustralia just committed $207 million to a major satellite program. What is it, and why do we need it?<figure><img src="https://images.theconversation.com/files/584628/original/file-20240327-26-vxzw2z.jpg?ixlib=rb-1.1.0&rect=0%2C3104%2C6162%2C4601&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Landsat image of Lake Torrens, South Australia.</span> <span class="attribution"><a class="source" href="https://earthobservatory.nasa.gov/images/150566/lake-torrens-is-a-lake-again">NASA Earth Observatory</a></span></figcaption></figure><p>Last week, the federal minister for Resources and Northern Australia, Madeleine King, <a href="https://www.usgs.gov/news/featured-story/usgs-and-australia-continue-partnership-landsat-next-satellite-mission">signed a A$207 million commitment with the United States</a> in support of “Landsat Next”.</p>
<p>Aptly named, this is the next generation of an Earth observation satellite program from which Australia has benefited for <a href="https://www.ga.gov.au/news/40-years-of-landsat-in-australia">over 40 years</a>.</p>
<p>The commitment means we will make a critical contribution to global Earth observation efforts with our cutting-edge data management. In essence, we will be the custodians of data downloaded from new Landsat satellites – a major role. </p>
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Read more:
<a href="https://theconversation.com/landsat-turns-50-how-satellites-revolutionized-the-way-we-see-and-protect-the-natural-world-186986">Landsat turns 50: How satellites revolutionized the way we see – and protect – the natural world</a>
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<h2>What is Earth observation?</h2>
<p>Earth observation satellites provide the world with more than half of all climate change data – and some of that data can come from nowhere else but space. They also provide over 90% of weather data, which the Bureau of Meteorology uses to give us our daily forecasts. </p>
<p>In Australia, Earth observation data <a href="https://www.spacegovcentre.org/_files/ugd/cd297f_ae32824561374ea0982b562ff8332507.pdf">is also critical for supporting</a> agriculture, fisheries, mining, land and <a href="https://www.csiro.au/en/news/all/articles/2018/april/satellite-water-monitoring">water policies</a>, bushfire response, and national security needs. In 2020, the economic benefits of Earth observation data were estimated at over <a href="https://www.deloitte.com/au/en/services/economics/perspectives/economics-earth-observation.html">A$2.4 billion</a>. </p>
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<span class="caption">Arrernte artwork by Roseanne Kemarre Ellis, Caterpillar Tracks, on a satellite antenna at the Alice Springs Ground Station.</span>
<span class="attribution"><a class="source" href="https://www.usgs.gov/media/images/aboriginal-art-satellite-dish">USGS</a></span>
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<p>Furthermore, such data brings immense benefits to First Nations people, particularly in northern Australia. Indigenous rangers use Earth observation data to augment their traditional land and water management practices.</p>
<p>Importantly, Geoscience Australia and CSIRO work closely with the <a href="https://cfat.org.au/cfat-se">Centre for Appropriate Technology</a>, an Indigenous business in Alice Springs. This business owns a satellite dish that receives data from Landsat and other Earth observation satellites.</p>
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Read more:
<a href="https://theconversation.com/painting-with-fire-how-northern-australia-developed-one-of-the-worlds-best-bushfire-management-programs-205113">‘Painting with fire’: how northern Australia developed one of the world’s best bushfire management programs</a>
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<h2>What is Landsat?</h2>
<p>Landsat is a program led by NASA and the US Geological Survey. <a href="https://landsat.gsfc.nasa.gov/">For more than 50 years</a> it has provided the “longest continuous space-based record of Earth’s land in existence”.</p>
<p>This means since 1972 we’ve had continuous data on ice melts, weather and temperature changes, and changes in the planet’s landscapes and freshwater sources.</p>
<p>Australia has been a Landsat beneficiary and partner since the early 1970s. Just earlier this year, emergency services in Queensland facing Cyclone Kirilly depended on Landsat data to <a href="https://www.canberratimes.com.au/story/8564305/australia-continues-partnership-in-satellite-program/">help mitigate potential flooding</a>. Geoscience Australia has also used Landsat data gathered over decades to <a href="https://landsat.gsfc.nasa.gov/article/shifting-shores-of-the-australian-continent-mapped-with-landsat/">map changes in Australia’s shorelines</a>.</p>
<p>And during the Black Summer megafires of 2019–20, the worst bushfire season New South Wales has ever recorded, <a href="https://www.dea.ga.gov.au/article/landsat-black-summer">Landsat images were critical</a> in predicting where the bushfires would be worst, and assisting in real-time response. </p>
<p>The new agreement places us at the centre of data management for the next generation of Landsat.</p>
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Read more:
<a href="https://theconversation.com/i-made-bushfire-maps-from-satellite-data-and-found-a-glaring-gap-in-australias-preparedness-132087">I made bushfire maps from satellite data, and found a glaring gap in Australia's preparedness</a>
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<h2>What is Landsat Next?</h2>
<p>There have been nine Landsat satellites since 1972, of which eight are operational today. Landsat Next will add three more satellites to this, with new capabilities. As a result, we will get more data more often, and at a higher resolution.</p>
<p>Landsat Next will significantly improve image resolution of some of the original satellites. This means, for example, that 40% more detail can be captured for agricultural sowing, irrigation and harvesting needs.</p>
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<span class="caption">The Great Barrier Reef imaged by Landsat in 1999.</span>
<span class="attribution"><a class="source" href="https://earthobservatory.nasa.gov/images/3270/great-barrier-reef">NASA Earth Observatory</a></span>
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<p>The current Landsat satellites cover 11 spectral bands. These are wavelengths of light captured by satellite sensors, ranging from visible light which we can see with the naked eye to invisible wavelengths like infrared and ultraviolet.</p>
<p>Landsat Next will increase this to up to 26 bands, which makes it possible to track water quality at much greater accuracy. This is helpful, for example, in detecting harmful algal blooms.</p>
<p>Landsat satellites also sense thermal bands. This is a measurement of surface temperatures so we can understand soil health and water levels, and track bushfires.</p>
<p>Landsat Next will improve the resolution of temperature measurements, providing improved climate change data and more accurate information for farmers and sustainable urban planning.</p>
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Read more:
<a href="https://theconversation.com/landsat-zooms-in-on-cities-hottest-neighborhoods-to-help-combat-the-urban-heat-island-effect-182925">Landsat zooms in on cities' hottest neighborhoods to help combat the urban heat island effect</a>
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<h2>Australia is great at satellite data</h2>
<p>The new commitment builds on what Australia already does, and is really good at – the ground and data segments of Earth observation satellite systems. In fact, we are a <a href="https://www.space.gov.au/about-agency/publications/earth-observation-space-roadmap">world leader in Earth observation data management</a>.</p>
<p><a href="https://www.youtube.com/watch?v=c6m8_2u91hA">We have excellent geography</a> for collecting data from the satellites via large satellite dishes in Alice Springs. We also have a longstanding tradition of being the data custodians and stewards for our US and European partners.</p>
<p>The Landsat Next agreement fulfils one aspect of the planned <a href="https://www.csiro.au/en/news/All/News/2022/March/National-Space-Mission-for-Earth-Observation">National Space Mission for Earth Observation</a> (NSMEO) which was cancelled last year due to <a href="https://www.abc.net.au/news/2023-06-29/labor-axes-morrison-government-satellite-program/102538686">major budget cuts</a>. This was a disappointment to many people in Australia, and to our international partners.</p>
<p>This new commitment to Landsat Next puts in place part of what we were already planning to do through the NSMEO, and will make us a more important partner in global Earth observation infrastructure.</p>
<p>With our unique geography, Australia is a heavy user of Earth observation data, and this agreement means we can be bigger contributors, as well.</p>
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Read more:
<a href="https://theconversation.com/the-first-ever-survey-on-australian-attitudes-towards-space-is-out-so-what-do-we-think-219813">The first-ever survey on Australian attitudes towards space is out. So, what do we think?</a>
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<p class="fine-print"><em><span>Cassandra Steer receives funding from Geoscience Australia and the Department of Defence. In the past she has received funding from the Australian Space Agency, DFAT, the Canadian Department of National Defence, the US Department of State, and the US Department of Defense.</span></em></p>Without satellites, we wouldn’t have much of the Earth and climate data we have today. And Australia is a world leader in satellite data.Cassandra Steer, Deputy Director, Institute for Space (InSpace), Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2236182024-02-23T17:16:47Z2024-02-23T17:16:47ZSatellites are burning up in the upper atmosphere – and we still don’t know what impact this will have on the Earth’s climate<figure><img src="https://images.theconversation.com/files/577600/original/file-20240223-16-tqd752.jpg?ixlib=rb-1.1.0&rect=25%2C16%2C5566%2C4174&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-illustration/satellite-hurtling-through-space-burning-enters-113962255">Paul Fleet / shutterstock</a></span></figcaption></figure><p>Elon Musk’s SpaceX has announced it will dispose of 100 Starlink satellites over the next six months, after it <a href="https://spacenews.com/spacex-to-deorbit-100-older-starlink-satellites/">discovered a design flaw</a> that may cause them to fail. Rather than risk posing a threat to other spacecraft, SpaceX will “de-orbit” these satellites to burn up in the atmosphere. </p>
<p>But atmospheric scientists are increasingly concerned that this sort of <a href="https://www.cbc.ca/radio/quirks/study-space-junk-pollution-1.7010373">apparent fly-tipping</a> by the space sector will cause further climate change down on Earth. One team recently, and unexpectedly, found <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10614211/">potential ozone-depleting metals</a> from spacecraft in the stratosphere, the atmospheric layer where the ozone layer is formed. </p>
<p>The relative “low earth orbit” where <a href="https://www.copernicus.eu/en/about-copernicus/infrastructure-overview/discover-our-satellites">satellites</a> monitoring Earth’s <a href="https://www.copernicus.eu/en">ecosystems</a> are found is increasingly congested – Starlink alone has more than 5,000 spacecraft in orbit. Clearing debris is therefore a priority for the space sector. Newly launched spacecraft must also be removed from orbit within 25 years (the US recently implemented a stricter <a href="https://www.fcc.gov/document/fcc-adopts-new-5-year-rule-deorbiting-satellites-0">five-year rule</a>) either by moving upwards to a so-called “graveyard orbit” or down into the Earth’s atmosphere. </p>
<p>Lower orbiting satellites are usually designed to use any remaining fuel and the pull of the Earth’s gravity to re-enter the atmosphere. In a controlled reentry, the spacecraft enters the atmosphere at a pre-set time to land in the most remote part of the Pacific Ocean at <a href="https://explorersweb.com/point-nemo-spacecraft-graveyard/">Point Nemo</a> (aka the spacecraft cemetery). In an uncontrolled re-entry, spacecraft are left to follow a “natural demise” and burn up in the atmosphere.</p>
<p>Nasa and the European Space Agency promote this form of disposal as part of a design philosophy called “design for demise”. It is an environmental challenge to build, launch and operate a satellite robust enough to function in the hostility of space yet also able to break up and burn up easily on re-entry to avoid dangerous debris reaching the Earth’s surface. It’s still a work in progress.</p>
<p>Satellite operators must prove their design and re-entry plans have a low “human-hit” rate before they are awarded a license. But there is limited concern regarding the impact on Earth’s upper atmosphere during the re-entry stage. This is not an oversight.</p>
<p>Initially, neither the space sector nor the astrophysics community considered burning up satellites on re-entry to be a serious environmental threat – to the atmosphere, at least. After all, the number of spacecraft particles released is small when compared with 440 tonnes of <a href="https://science.nasa.gov/solar-system/meteors-meteorites/">meteoroids</a> that enter the atmosphere daily, along with volcanic ash and human-made pollution from industrial processes on Earth.</p>
<h2>Bad news for the ozone layer?</h2>
<p>So are atmospheric climate scientists overreacting to the presence of spacecraft particles in the atmosphere? Their concerns draw on 40 years of research into the cause of the ozone holes above the south and north poles, that were first widely observed in the 1980s. </p>
<p>Today, they now know that ozone loss is caused by human-made <a href="https://gml.noaa.gov/hats/publictn/elkins/cfcs.html#:%7E:text=Chlorofluorocarbons%20(CFCs)%20are%20nontoxic%2C,as%20solvents%2C%20and%20as%20refrigerants.">industrial gases</a>, which combine with natural and very high altitude <a href="https://www.bas.ac.uk/data/our-data/publication/polar-stratospheric-clouds-satellite-observations-processes-and-role-in-ozone/">polar stratospheric clouds</a> or mother of pearl clouds. The surfaces of these ethereal clouds act as catalysts, turning benign chemicals into more active forms that can rapidly <a href="https://uk-air.defra.gov.uk/research/ozone-uv/moreinfo?view=arctic-ozone-hole">destroy ozone</a>.</p>
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<a href="https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Colourful cloud in night sky" src="https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577628/original/file-20240223-24-fpxid9.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">Mother of pearl cloud in the stratosphere above Norway.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/mother-pearl-cloud-norway-245-1849794832">Uwe Michael Neumann / shutterstock</a></span>
</figcaption>
</figure>
<p>Dan Cziczo is an atmospheric scientist at Purdue University in the US, and a co-author of the recent study that found ozone depleting substances in the stratosphere. He explains to me that the question is whether the new particles from spacecraft will help the formation of these clouds and lead to ozone loss at a time when the Earth’s atmosphere is just <a href="https://theconversation.com/how-science-saved-the-ozone-layer-218839">beginning to recover</a>. </p>
<p>Of more concern to atmospheric scientists such as Cziczo is that only a few new particles could create more of these types of polar clouds – not only at the upper atmosphere, but also in the lower atmosphere, where cirrus clouds form. Cirrus clouds are the thin, wispy ice clouds you might spot high in the sky, above six kilometres. They tend to let heat from the sun pass through but then trap it on the way out, so in theory more cirrus clouds could add extra global warming on top of what we are already seeing from greenhouse gases. But this is uncertain and <a href="https://blogs.esa.int/campaignearth/2023/03/23/in-the-icy-mountains-of-norway-a-fons-researcher-is-studying-how-clouds-affect-global-warming/">still being studied</a>.</p>
<p>Cziczo also explains that from anecdotal evidence we know that the high-altitude clouds above the poles are changing – but we don’t know yet what is causing this change. Is it natural particles such as meteoroids or volcanic debris, or unnatural particles from spacecrafts? This is what we need to know.</p>
<h2>Concerned, but not certain</h2>
<p>So how do we answer this question? We have some research from atmospheric scientists, spacecraft builders and astrophysicists, but it’s not rigorous or focused enough to make informed decisions on which direction to take. Some astrophysicists claim that alumina (aluminium oxide) particles from spacecraft will cause chemical reactions in the atmosphere that <a href="https://www.space.com/starlink-satellite-reentry-ozone-depletion-atmosphere">will likely trigger ozone destruction</a>. </p>
<p>Atmospheric scientists who study this topic in detail have not made this jump as there isn’t enough scientific evidence. We know particles from spacecraft are in the stratosphere. But what this means for the ozone layer or the climate is still unknown.</p>
<p>It is tempting to overstate research findings to garner more support. But this is the path to research hell – and deniers will use poor findings at a later date to discredit the research. We also don’t want to use populist opinions. But we’ve also learnt that if we wait until indisputable evidence is available, it may be too late, as with the loss of ozone. It’s a constant dilemma.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?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"></span>
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<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<hr><img src="https://counter.theconversation.com/content/223618/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Fionagh Thomson has carried out consultancy work for the UK space agency. She is an elected member of the sustainability committees for the Royal Astronomical Society and the European Astronomical society. </span></em></p>We know particles from spacecrafts are in the stratosphere. But what this means for the ozone layer or the climate is still unknown.Fionagh Thomson, Senior Research Fellow (visual ethnographer), Durham UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2232752024-02-23T13:48:54Z2024-02-23T13:48:54ZWar in Ukraine at 2 years: Destruction seen from space – via radar<figure><img src="https://images.theconversation.com/files/577463/original/file-20240222-27-6vdacx.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C742%2C589&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Satellite radar data shows the complete destruction of the Ukrainian city of Bakhmut.</span> <span class="attribution"><a class="source" href="https://www.sciencedirect.com/science/article/pii/S2666592124000064">Xu et al. (2024)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>As soldiers and citizens provide information from the front lines and affected areas of the war in Ukraine – two years old as of Feb. 24, 2024 – in quasi-real time, an active <a href="https://www.wired.com/story/open-source-intelligence-war-russia-ukraine/">open-source intelligence community</a> has formed to keep track of troop activity, destruction and other aspects of the war. </p>
<p>Remote sensing complements this approach, offering a safe means to study inaccessible or dangerous areas. For example, seismologists have documented the high pace of <a href="https://doi.org/10.1038/s41586-023-06416-7">bombardments and firing of artillery</a> around Kyiv during the first few months of the war. </p>
<p>Previously, <a href="https://scholar.google.com/citations?hl=en&user=-Yl3IoQAAAAJ&view_op=list_works&sortby=pubdate">Teng Wang</a>, a professor at the Peking University in China, and <a href="https://scholar.google.com/citations?hl=en&user=1vR8GGoAAAAJ&view_op=list_works&sortby=pubdate">I</a> – both Earth scientists – studied <a href="https://www.science.org/doi/10.1126/science.aar7230">illegal nuclear tests in North Korea</a> with satellite data. </p>
<p>Putting our skills to good use once again, we, with graduate student <a href="https://www.researchgate.net/profile/Xu-Hang-3">Hang Xu</a>, have <a href="https://doi.org/10.1016/j.nhres.2024.01.006">analyzed the development of the war from space</a>. We exclusively used open-source, freely accessible data to ensure that all our findings could be reproduced, guaranteeing transparency and neutrality. </p>
<h2>View from above</h2>
<p>Sensors on satellites record electromagnetic waves radiated or reflected from Earth’s surface with wavelengths ranging from hundreds of nanometers to tens of centimeters, enabling semi-continuous <a href="https://earth.jaxa.jp/en/eo-knowledge/eosatellite-type/index.html">monitoring on a global scale</a>, unimpeded by political boundaries and natural obstacles. </p>
<p>Optical images, the equivalent of photographs taken from space, help governments, researchers and journalists monitor troop movements on the front and the destruction of equipment and facilities. Although optical images are easily interpreted, they suffer from cloud cover and operate only during daylight. </p>
<p>To counter these issues, we used radars onboard satellites. Space-borne radar systems beam long-wavelength electromagnetic waves toward the Earth and then record the returning echos. These waves – about 0.4 to 4 inches (1 to 10 centimeters) – can penetrate clouds and smoke. <a href="https://nisar.jpl.nasa.gov/mission/get-to-know-sar/interferometry/">Radar interferometry</a> has already proved to be an invaluable tool to monitor widespread damage caused by <a href="http://dx.doi.org/10.26443/seismica.v2i3.502">natural disasters</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a pair of satellite views showing the same section of a city, one with intact buildings and green space and the other damaged or destroyed buildings and charred earth" src="https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=757&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=757&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=757&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=952&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=952&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577455/original/file-20240222-26-fyycrl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=952&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Satellite photography like these ‘before’ and ‘after’ images can provide a visceral sense of the destruction in the war in Ukraine.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/maxar-satellite-imagery-comparing-the-before-after-news-photo/1255499859">Satellite image (c) 2023 Maxar Technologies via Getty Images</a></span>
</figcaption>
</figure>
<h2>Radar from space</h2>
<p>Free and publicly available radar data for civilian applications is rare – the United States is scheduled to launch its <a href="https://nisar.jpl.nasa.gov/mission/quick-facts/">first one</a> in March 2024 – but the European Space Agency has made such data available since the early 1990s. Data from the European Space Agency’s <a href="https://sentinels.copernicus.eu/web/sentinel/missions/sentinel-1/data-products">Sentinel-1</a> satellite radar is freely accessible via their data hub. </p>
<p>Two radar images formed over the same area can be used to detect changes to structures and other surfaces. Interferometry measures <a href="https://nisar.jpl.nasa.gov/mission/get-to-know-sar/interferometry/">the difference in travel time between two radar signals</a>, which is a measure of change in the shape or position of surfaces. Another measure of surface change is the coherence of the reflected signals – that is, the degree of similarity between two different images when comparing neighboring pixels at the same position in the two images. A large coherence implies little change and thus the preservation of a building or other structure. On the other hand, a loss of coherence in the context of a battlefield implies damage or destruction of a building or structure. </p>
<p>Sentinel-1 radar’s spatial resolution of 66 feet (20 meters) over a swath of 255 miles (410 kilometers) combined with 12-day updates makes its radar data ideal for monitoring urban warfare. Previous research efforts have used satellite radar data to assess damage in <a href="https://doi.org/10.3390/rs14246239">Kyiv</a> and <a href="https://doi.org/10.3390/rs15123096">Mariupol</a>. We used the data to analyze the evolution of damage to cities over time during several lengthy battles.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="four maps of a city with increasing amounts of the buidlings marked in red" src="https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=487&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=487&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=487&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=612&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=612&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577471/original/file-20240222-24-cgcs3i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=612&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Changes in radar data during the battle of Bahkmut show increasing amounts of destruction. Red pixels imply damaged or destroyed buildings.</span>
<span class="attribution"><a class="source" href="https://www.sciencedirect.com/science/article/pii/S2666592124000064">Xu et al. (2024)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>Measure of destruction</h2>
<p>We flagged highly damaged areas by comparing radar coherence before and after the war, within the areas classified as artificial surfaces by the European Space Agency’s <a href="https://worldcover2021.esa.int/">WorldCover 2021 dataset</a>. Using this approach, we first analyzed the <a href="https://www.usnews.com/news/world/articles/2023-05-20/key-moments-in-the-battle-of-bakhmut-in-ukraines-east">battle of Bakhmut</a>, one of the longest and bloodiest of the war, which began on Oct. 8, 2022, and ended with a Russian victory on May 20, 2023. </p>
<p>When Hang Xu showed Teng Wang and me the data he had processed, we were puzzled. We saw a checkerboard pattern all over the city. We quickly realized the horror of the situation. The only thing that survived after the yearlong battle was the network of roads in the city. All buildings had partially or completely collapsed due to the continuous bombardment.</p>
<p>We then took a look at the battles of Rubizhne, Sievierodonetsk and Lysychansk that started in April 2022 and ended with a Russian victory on July 2, 2022. The comparatively lower destruction of Lysychansk is explained by the rapid encirclement of the city from the south instead of continued frontal assaults, as was the case in Bakhmut. The radar data reveals destruction away from the front line within cities, showing the whole extent of the devastation. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="four maps of a set of three cities with increasing amounts of the buidlings marked in red" src="https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=488&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=488&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=488&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=613&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=613&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577472/original/file-20240222-18-3rco59.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=613&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Changes in radar data during the battles of Rubizhne, Sievierodonetsk and Lysychansk show increasing amounts of destruction. Urban areas are shown in gray with damage in red.</span>
<span class="attribution"><a class="source" href="https://www.sciencedirect.com/science/article/pii/S2666592124000064">Xu et al. (2024)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>Devastation in focus</h2>
<p>Remote sensing images offer the means to safely monitor the impact of armed conflicts, particularly as <a href="https://thedocs.worldbank.org/en/doc/8bc2ffd2ca0d2f174fee8315ad4c385b-0090082021/original/Classification-of-Fragility-and-Conflict-Situations-web-FY22.pdf">high-intensity wars</a> in <a href="https://www.nytimes.com/interactive/2024/02/01/world/middleeast/Israel-gaza-war-demolish.html">urban environments proliferate</a>. Open-access satellite instruments complement other forms of open-source intelligence by offering unimpeded access to high-resolution, unbiased information, which can help people grasp the true impact of war on the ground. </p>
<p>The picture is clear: The real story of war is <a href="https://www.rferl.org/a/bakhmut-ukraine-satellite-images-maxar-destruction/32416025.html">destruction</a>.</p><img src="https://counter.theconversation.com/content/223275/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sylvain Barbot receives funding from the National Science Foundation. </span></em></p>Satellite photography of the Ukrainian city of Bakhmut shows block after block of destroyed buildings. Satellite radar provides a different view – a systematic look at the destruction of the whole city.Sylvain Barbot, Associate Professor of Earth Sciences, USC Dornsife College of Letters, Arts and SciencesLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2238772024-02-20T18:24:56Z2024-02-20T18:24:56ZCybersecurity for satellites is a growing challenge, as threats to space-based infrastructure grow<figure><img src="https://images.theconversation.com/files/576506/original/file-20240219-26-38pqkp.jpg?ixlib=rb-1.1.0&rect=17%2C0%2C3976%2C2994&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-illustration/satellite-over-earth-119852509">Andrzej Puchta / Shutterstock</a></span></figcaption></figure><p>In today’s interconnected world, <a href="https://www.esa.int/Enabling_Support/Preparing_for_the_Future/Discovery_and_Preparation/Space_technology_for_life_on_Earth">space technology forms the backbone</a> of our global communication, navigation and security systems. Satellites orbiting Earth are pivotal for everything from GPS navigation to international banking transactions, making them indispensable assets in our daily lives and in global infrastructure.</p>
<p>However, as our dependency on these celestial guardians escalates, so too does their allure to adversaries who may seek to compromise their functionality through cyber means. A satellite’s service could be interrupted, or at worst the spacecraft could be disabled. The expansion of the digital realm into space has opened new frontiers for cyber threats, posing unprecedented challenges.</p>
<p>This emerging battleground highlights the urgent need for robust cybersecurity measures to protect our space assets from sophisticated attacks that threaten global stability and security. </p>
<p>Recent cyber incidents, such as the <a href="https://news.viasat.com/blog/corporate/ka-sat-network-cyber-attack-overview">2022 attack on the KA-SAT network</a>, highlight the immediate vulnerability of satellites. The network, owned by global communications giant Viasat, faced a sophisticated cyber assault that disrupted its services across Europe. While the perpetrators have not been officially confirmed, many suspect Russia’s involvement.</p>
<p>As we witness an increase in state-sponsored attacks and the commercialisation of hacking tools, the stakes for securing space assets extend beyond technical challenges to encompass potential disruption to the world economy and diplomatic relations between countries that operate satellite networks. The focus on space security has been thrown into the spotlight recently by the claim that Russia is developing a <a href="https://theconversation.com/russias-space-weapon-anti-satellite-systems-are-indiscriminate-posing-a-risk-to-everyones-spacecraft-223935">space-based anti-satellite weapon</a> – possibly one that’s nuclear-powered.</p>
<h2>Evolving threats</h2>
<p>The shift from analogue to digital has transformed space technology vulnerabilities, <a href="https://www.lse.ac.uk/ideas/projects/space-policy/publications/Cyberattacks-on-Satellites#:%7E:text=Cyber%2Dattacks%20on%20satellites%20are,operators%20for%20obvious%20commercial%20reasons.">exposing them to a spectrum of cyber threats</a>. Initially, from the late 1950s onwards, concerns centred around physical tampering and espionage, but as the technology advanced, digital vulnerabilities became the forefront of security challenges. </p>
<p>With adversaries now employing artificial intelligence (AI) and machine learning to find new vulnerabilities, the complexity of attacks goes well beyond traditional strategies for defending satellites.</p>
<p>Early breaches such as the <a href="https://www.usni.org/magazines/proceedings/2021/february/asat-goes-cyber#:%7E:text=In%20late%201998%2C%20a%20joint,although%20direct%20evidence%20is%20scarce.">hacking of US-German satellites in 1998</a> were precursors to the complex cybersecurity landscape we navigate today. Modern adversaries leverage sophisticated techniques to exploit vulnerabilities in satellite communications and data transmission, aiming to disrupt, intercept, or corrupt the invaluable data they carry. </p>
<p>This evolution signifies a pivotal shift in how we must approach the security of space technology, underscoring the importance of anticipating and mitigating digital threats. This includes end-to-end encryption to make data transmission harder to hack or disrupt, and better detection of suspicious activity in advance of an attack. There’s a cost to implementing these security measures, however, such as limitations on computer processing power and bandwidth.</p>
<h2>Vulnerabilities in the void</h2>
<p>The isolation of satellites in orbit and their reliance on wireless communications expose them to specific threats such as signal jamming, spoofing – disguising communications from a suspicious source as those of a known, trusted source – and the interception of data. </p>
<p>Additionally, the limitations on processing power and bandwidth in space exacerbate the challenge of implementing routine software updates and patches, leaving systems vulnerable to exploitation. </p>
<p>Software vulnerabilities within satellite systems can be exploited from great distances, allowing attackers to potentially take control of them. This vulnerability is compounded by the ever-increasing complexity of satellites and their software. </p>
<p>The void of space does not shield these assets from cyber adversaries; instead, it presents a domain rife with unique challenges. These challenges require innovative solutions.</p>
<p>In response to these escalating cyber threats, a united front has formed among space agencies, technology companies and security experts. This effort is focused on developing robust defence mechanisms to protect satellites and other space-based technologies. </p>
<p>Key initiatives include establishing secure communication protocols, implementing end-to-end encryption for data transmission, and deploying AI-powered anomaly detection systems to identify suspicious activities in satellite networks. Beyond initiatives by <a href="https://www.nasa.gov/general/nasa-issues-new-space-security-best-practices-guide/">Nasa</a> and the <a href="https://www.esa.int/Space_Safety">European Space Agency (Esa)</a>, <a href="https://www.weforum.org/agenda/2022/05/increased-cybersecurity-for-space-based-services/">other international collaborations</a> have taken shape, reflecting a widespread commitment to space cybersecurity. </p>
<p>Agreements among countries in the <a href="https://www.forbes.com/advisor/business/what-is-five-eyes/">Five Eyes intelligence alliance</a> (consisting of the US, UK, Canada, Australia and New Zealand) and partnerships with private-sector leaders in space technology underscore the global acknowledgment of the importance of securing space assets. These cooperative endeavours are crucial not only for safeguarding national security interests, but for ensuring the uninterrupted operation of the myriad services that rely on space technology.</p>
<h2>Cyber defences in space</h2>
<p>The development of AI-driven security protocols and quantum encryption is poised to revolutionise the protection of space assets. </p>
<p>AI-driven security offers the potential to predict and counteract cyber threats in real-time, continually adapting to new challenges. However, this technology is still under development and faces significant challenges, including the availability of limited data sets for training in the unique context of space. </p>
<p>Similarly, <a href="https://www.ibm.com/topics/quantum-cryptography">quantum encryption</a> in theory offers impervious security by making use of the field of physics known as quantum mechanics. But this is still in the research and development stage for space applications – practical deployment of such technologies in space will require a great deal more innovation and testing.</p>
<h2>Global implications</h2>
<p>Cybersecurity in space extends far beyond the technical realm, affecting international relations, cooperation, and competition. There is a drive towards greater protection for space infrastructure. International collaboration would be ideal to achieve this, but such an aim faces challenges due to competing interests and varying levels of trust between nations. </p>
<p>The economic repercussions of cyberattacks on space infrastructure are profound. A significant cyber incident could cost billions in damages, disrupting global services and requiring extensive resources for mitigation and recovery. </p>
<p>The complex interplay between the need for collective security measures, the hurdles in achieving global cooperation, and the potential for catastrophic economic impact underscores the intricate relationships between cybersecurity in space, international relations, and economic stability.</p>
<p>Progress in cybersecurity measures in outer space is not just a technical necessity but a global imperative, to safeguard the future of space exploration and the integrity of critical space infrastructure. Addressing the evolving landscape of cyber threats demands ongoing vigilance, innovation, and a unified approach among all those involved in spaceflight.</p><img src="https://counter.theconversation.com/content/223877/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sylvester Kaczmarek is chief technology officer at OrbiSky Systems.</span></em></p>The capability for attacking satellites in space using cyber technology is advancing fastSylvester Kaczmarek, Chief Technology Officer, Imperial College LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2239352024-02-19T18:27:05Z2024-02-19T18:27:05ZRussia’s space weapon: anti-satellite systems are indiscriminate, posing a risk to everyone’s spacecraft<figure><img src="https://images.theconversation.com/files/576566/original/file-20240219-22-dvgtci.jpg?ixlib=rb-1.1.0&rect=11%2C22%2C7657%2C5725&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/telecommunication-satellite-providing-global-internet-network-2375569273">NicoElNino / Shutterstock</a></span></figcaption></figure><p>In a week where national security has <a href="https://www.theguardian.com/us-news/2024/feb/12/trump-nato-russia-comments-republicans">taken centre stage in Washington</a>, the White House confirmed on Thursday that it had evidence that Russia was developing a <a href="https://www.bbc.co.uk/news/world-us-canada-68309496">space-based nuclear anti satellite weapon</a>.</p>
<p>John Kirby, the National Security Council spokesperson, <a href="https://www.theguardian.com/us-news/2024/feb/15/russia-anti-satellite-weapon-space-white-house">informed reporters</a> that the White House believe Russia’s programme to be “troubling”, despite “no immediate threat to anyone’s safety”. </p>
<p>The problem is that, depending on what type of weapon this is, the consequences of using it could be indiscriminate – threatening everyone’s satellites and causing a breakdown of the vital services that come from space infrastructure.</p>
<p>The White House revelations come after House Intelligence Committee Chairman Mike
Turner urged the administration, late on Wednesday, to declassify information
concerning what he called a “serious national security threat”. There were then several days <a href="https://news.sky.com/story/republican-warns-of-national-security-threat-amid-fears-of-russian-space-weapon-13071884">of comments</a> and speculation about Russia <a href="https://nymag.com/intelligencer/article/u-s-officials-dont-freak-out-about-russian-nukes-in-space.html">either being ready to launch a nuclear weapon into space</a>, or deploying an anti-satellite <a href="https://spacenews.com/white-house-confirms-it-has-intelligence-on-russians-anti-satellite-weapon-but-says-no-immediate-threat/">weapon powered by nuclear energy</a>.</p>
<p>Kirby did not fully outline the nature of the threat, <a href="https://www.independent.co.uk/news/world/americas/us-politics/national-security-threat-update-russia-b2497015.html">but he added</a> that officials believed the weapons system was not an “active capability” and had not been deployed. To reassure those listening, Kirby said that the weapon was not one that could be used to cause physical destruction on Earth but that the White House was monitoring Russian activity and would “continue to take it very seriously”.</p>
<p>During a visit to Albania on Thursday, Secretary of State Antony Blinken confirmed the news and stated that he expected to have more to say soon, adding that the Biden administration was “also conferring with allies and partners on the issue”.</p>
<p>While discussing the matter with Indian Foreign Minister Jaishankar and Chinese
Foreign Minister Wang Yi at the <a href="https://securityconference.org/en/">Munich Security Conference</a>, Blinken is <a href="https://www.independent.co.uk/news/world/europe/joe-biden-ap-russia-antony-blinken-washington-b2497667.html">reported</a> to have “emphasised that the pursuit of this capability should be a matter of concern”.</p>
<h2>Denials from Russia</h2>
<p>Moscow immediately denied the existence of such a programme and <a href="https://www.reuters.com/world/kremlin-dismisses-us-warning-about-russian-nuclear-capability-space-2024-02-15/">stated</a> that it was a “malicious fabrication” created by the Biden administration to pressurise Congress into passing the USD$97bn (£77bn) <a href="https://edition.cnn.com/2024/02/12/politics/senate-foreign-aid-bill-ukraine/index.html">foreign aid bill</a>, $60bn of which was destined for Ukraine. Kremlin spokesman Dmitry Peskov <a href="https://www.reuters.com/world/kremlin-dismisses-us-warning-about-russian-nuclear-capability-space-2024-02-15/">told reporters</a>: “It is obvious that the White House is trying, by hook or by crook, to encourage Congress to vote on a bill to allocate money; this is obvious”. </p>
<p><a href="https://www.whitehouse.gov/briefing-room/speeches-remarks/2024/02/16/remarks-by-president-biden-on-the-reported-death-of-aleksey-navalny/">At a press conference</a> on the death of Russian opposition leader Alexei Navalny, Joe Biden stated that there was “no nuclear threat to the people of America or anywhere else in the world with what Russia is doing at the moment”.</p>
<figure class="align-center ">
<img alt="Orbital debris" src="https://images.theconversation.com/files/576569/original/file-20240219-20-pya8br.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/576569/original/file-20240219-20-pya8br.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/576569/original/file-20240219-20-pya8br.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/576569/original/file-20240219-20-pya8br.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/576569/original/file-20240219-20-pya8br.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/576569/original/file-20240219-20-pya8br.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/576569/original/file-20240219-20-pya8br.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">
<figcaption>
<span class="caption">Space is already crowded with human-made objects and anti-satellite weapons can make the situation much worse.</span>
<span class="attribution"><a class="source" href="https://orbitaldebris.jsc.nasa.gov/photo-gallery/">NASA ODPO</a></span>
</figcaption>
</figure>
<p>The president added that there was “no evidence that they have made a decision to go forward with doing anything in space either”. If Moscow did decide to go ahead with the programme it would be contrary to the <a href="https://www.unoosa.org/pdf/publications/STSPACE11E.pdf">Outer Space Treaty</a> which 130 countries have signed onto, including Russia.</p>
<p>The treaty prohibits “nuclear weapons or any other kinds of weapons of mass
destruction” in orbit or stationing weapons in outer space “in any other manner”.
Anti-satellite weapons are nothing new. <a href="https://swfound.org/media/9550/chinese_asat_fact_sheet_updated_2012.pdf">China launched a
weapon</a> to destroy a non-operational weather satellite in January 2007. </p>
<p>While the temptation to launch a nuclear strike in space may seem alluring to nations looking to challenge US dominance in the domain, such actions come at huge risk. It is not necessarily the destruction of objects in space from Earth that should be the primary concern when it comes to anti-satellite weapons more generally, but the effect they have in space.</p>
<h2>Mass of debris</h2>
<p>The destruction of any celestial object creates a mass of debris varying in size from a few millimetres to several centimetres. Currently, there are hundreds of millions of tracked pieces of space debris orbiting <a href="https://earth.org/space-junk-what-is-it-what-can-we-do-about-it/">the Earth</a>.</p>
<p>The speed at which this space debris is travelling makes it a major hazard to other satellites and entities in space such as the International Space Station (ISS), which has to change course in order to avoid collisions which can cause widespread damage. The ISS has had to <a href="https://www.space.com/international-space-station-space-debris-spacex-dragon-spacecraft-arrival">changed course 32 times since 1999</a>.</p>
<p>Once space debris has been created, it is almost impossible to control the trajectory after the strike or the orbital pattern it will take around the Earth. This can put a nation’s space assets – such as its satellites – at the same risk of destruction as that of an adversary. This situation has been described in similar terms to that applied to nuclear weapons on Earth, <a href="https://www.guspaceinitiative.org/contentmaster/mutually-assured-destruction-in-low-earth-orbit">in terms of mutually assured destruction</a>.</p>
<p>If a nuclear strike were to be conducted by a nation in space with the intention of destroying satellites and also to demonstrate both an ability and willingness to use nuclear weapons more generally, it would be next to impossible to control the consequences of such an action.</p>
<p>It would be fairly certain that such a strike would have the intended effect in reducing the space capabilities of an opponent. For example, an attack on US assets could disable the satellite-based global positioning system (GPS) that is relied on by western nations. </p>
<p>There is, however, the very real possibility that it would also destroy the space assets of the nation behind the attack, as well as allies and friends of that same nation. This could lead to tensions being raised and lead to a loss of that country’s support.</p>
<p>The inability to control the effects of attacks in space, whether they originate from a weapon in space or on the Earth, makes such actions subject to a great degree of consideration and debate in all nations that are active in the space domain.</p><img src="https://counter.theconversation.com/content/223935/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>Destroying satellites in space can lead to cascades that are hard to predict.Matthew Powell, Teaching Fellow in Strategic and Air Power Studies, University of PortsmouthDafydd Townley, Teaching Fellow in International Security, University of PortsmouthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2237022024-02-17T17:01:41Z2024-02-17T17:01:41ZIs Russia looking to put nukes in space? Doing so would undermine global stability and ignite an anti-satellite arms race<p>Fresh U.S. <a href="https://www.voanews.com/a/us-confirms-russia-pursuing-space-based-anti-satellite-system-/7489975.html">intelligence</a> circulating in Congress reportedly indicates that Russia is developing an <a href="https://www.space.com/anti-satellite-weapons-asats">anti-satellite</a> weapon in space with a <a href="https://www.politico.com/news/2024/02/14/house-intel-national-security-threat-russia-space-power-00141473">nuclear component</a>.</p>
<p>News reports speculating about what the weapon could be abounded after Rep. Mike Turner, R-Ohio, chair of the House Intelligence Committee, released <a href="https://www.cnn.com/2024/02/14/politics/house-intel-chairman-serious-national-security-threat/index.html">a cryptic but alarming statement</a> on Feb. 14, 2024, regarding the information, which he framed as a “serious national security threat.” Some sources suggested a <a href="https://www.cnn.com/videos/world/2024/02/17/russian-nuclear-space-weapon-oren-liebermann-lklv-cntmwknd-vpx.cnn">nuclear weapon</a>. Others suspect a <a href="https://www.reuters.com/technology/space/russia-seen-highly-unlikely-put-nuclear-warhead-space-2024-02-15/">weapon that is nuclear-powered</a> but not a nuclear warhead.</p>
<p>The White House <a href="https://www.whitehouse.gov/briefing-room/press-briefings/2024/02/15/press-briefing-by-press-secretary-karine-jean-pierre-and-white-house-national-security-communications-advisor-john-kirby-3/">confirmed</a> the following day that the Russian system under development is a space-based anti-satellite weapon and that if it were deployed, it would violate the <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/outerspacetreaty.html">1967 Outer Space Treaty</a>, which bans weapons of mass destruction in space. The Kremlin responded by <a href="https://www.reuters.com/world/kremlin-dismisses-us-warning-about-russian-nuclear-capability-space-2024-02-15/">dismissing the reports</a> as a “malicious fabrication.” </p>
<p>While the exact weapon remains unknown to the public, the events raise the specter of nuclear weapons in space at a tense time. Relations between the United States and Russia are at their lowest in decades, and Russia is currently waging a war of aggression in Ukraine. </p>
<p>As a <a href="https://ucigcc.org/people/spenser-warren/">scholar of nuclear strategy</a>, I know the U.S. reports come at a time when the nuclear world order is shifting significantly. <a href="https://aparc.fsi.stanford.edu/publication/chinas-nuclear-enterprise">China</a> and <a href="https://www.armscontrol.org/act/2023-01/news/north-korea-plans-expand-nuclear-arsenal#:%7E:text=After%20an%20unprecedented%20year%20of,have%2040%E2%80%9350%20nuclear%20warheads.">others</a> are <a href="https://www.theguardian.com/world/2023/oct/20/china-expanding-nuclear-arsenal-much-faster-than-predicted-us-report-says">expanding</a> and <a href="https://carnegieendowment.org/2022/07/18/striking-asymmetries-nuclear-transitions-in-southern-asia-pub-87394">modernizing</a> their arsenals. <a href="https://foreignpolicy.com/2023/05/07/iran-nuclear-deal-jcpoa-us-trump-biden-nonproliferation-diplomacy/">Iran</a> is <a href="https://www.wsj.com/world/middle-east/iran-maintains-steady-expansion-of-nuclear-program-46df894a">close</a> to being able to produce a <a href="https://theconversation.com/iran-and-the-us-appear-unlikely-to-reach-a-new-nuclear-deal-leaving-everyone-more-unsafe-190100">nuclear weapon</a>. <a href="https://thebulletin.org/2024/02/even-in-the-face-of-russian-aggression-a-nuclear-eurodeterrent-is-still-a-bad-idea/">Other countries</a> may eventually want their <a href="https://carnegieendowment.org/2023/02/13/south-korea-s-nuclear-flirtations-highlight-growing-risks-of-allied-proliferation-pub-89015">own</a> nuclear weapons.</p>
<p>At the same time, <a href="https://warontherocks.com/2023/09/proliferate-dont-obliterate-how-responsive-launch-marginalizes-anti-satellite-capabilities/">several countries</a> are developing <a href="https://hir.harvard.edu/anti-satellite-weapons-and-the-emerging-space-arms-race/">new weapons</a> to attack targets in space. This list includes <a href="https://meduza.io/en/feature/2021/11/18/russia-s-asat-missile-test-in-context">Russia</a>, the <a href="https://time.com/6168148/space-weapons-ban-harris/">U.S.</a>, <a href="https://thediplomat.com/2022/06/chinas-directed-energy-weapons-and-counterspace-applications/">China</a> and <a href="https://www.orfonline.org/expert-speak/asat-weapons">India</a>, although none currently field weapons in space.</p>
<h2>Cold War schemes</h2>
<p>The recent revelations about Russian space weapons raise the specter that countries may decide to deploy nuclear weapons in space at some point. Some have tried before.</p>
<p>The <a href="https://doi.org/10.1080/09592296.2022.2062130">U.S.</a> and <a href="https://doi.org/10.1080/10736700600861418">Soviet Union</a> <a href="https://apnews.com/article/russia-space-nuclear-satellite-threats-5da6e43c9b4fdb04269ca85a5381aa4a">researched</a> nuclear detonations in space during the Cold War. In the late 1960s, the Soviets tested a missile <a href="https://www.popularmechanics.com/military/weapons/a27888/the-secret-soviet-space-weapon-mistaken-for-a-ufo/">that could be placed in low Earth orbit</a> and be capable of coming out of orbit and <a href="https://www.ausairpower.net/APA-Sov-FOBS-Program.html">carrying a nuclear warhead</a> to Earth.</p>
<figure class="align-center ">
<img alt="A man stands in front of red, blue and white flags and next to large rockets." src="https://images.theconversation.com/files/576287/original/file-20240217-28-sdnnvv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/576287/original/file-20240217-28-sdnnvv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/576287/original/file-20240217-28-sdnnvv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/576287/original/file-20240217-28-sdnnvv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/576287/original/file-20240217-28-sdnnvv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/576287/original/file-20240217-28-sdnnvv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/576287/original/file-20240217-28-sdnnvv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Russian President Vladimir Putin delivers a speech during his visit to the Vostochny cosmodrome on April 12, 2022.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/russian-president-vladimir-putin-delivers-a-speech-during-news-photo/1239929978?adppopup=true">Yevgeny Biyatov/Sputnik/AFP via Getty Images</a></span>
</figcaption>
</figure>
<p>Neither country placed nuclear weapons in space permanently. Both were parties to the Outer Space Treaty and the <a href="https://treaties.un.org/pages/showDetails.aspx?objid=08000002801313d9">1963 Partial Test Ban Treaty</a>, which outlawed nuclear detonations in space. Moscow and Washington negotiated these treaties to contain the Cold War arms race.</p>
<p>These treaties constrained behavior in the late Cold War. However, Russian <a href="https://carnegieendowment.org/2017/03/30/after-deployment-what-russian-violations-of-inf-treaty-pub-68514">violations</a> of nuclear arms control treaties, as well as <a href="https://2017-2021.state.gov/u-s-withdrawal-from-the-inf-treaty-on-august-2-2019/">U.S.</a> and <a href="https://www.csis.org/analysis/russia-suspends-new-start-and-increases-nuclear-risks">Russian</a> <a href="https://www.brookings.edu/articles/the-looming-us-withdrawal-from-the-open-skies-treaty/">withdrawal</a> from <a href="https://www.armscontrol.org/act/2023-06/news/russia-formally-withdraws-cfe-treaty">various treaties</a> <a href="https://carnegieendowment.org/2021/12/13/u.s.-exit-from-anti-ballistic-missile-treaty-has-fueled-new-arms-race-pub-85977">since 2002</a>, suggest they may not in the future.</p>
<h2>Nukes in space</h2>
<p>But why would a country want space nukes? There are a few reasons.</p>
<p>Countries could point space-based nuclear weapons toward Earth. In theory, weapons from space could avoid early detection radars and missile defenses. However, there are significant disadvantages to firing nuclear weapons <a href="https://rlg.fas.org/810104-space.htm">directly from space</a>.</p>
<p>Placing weapons in space to strike targets on Earth may have defensive or offensive motivations. Weapons that evade missile defenses might ensure nuclear deterrence. This is a defensive strategy intended to prevent aggression against the state that placed them in space.</p>
<p>Alternatively, these weapons may help a country achieve a first-strike capability. A first strike requires the ability to destroy enough of an adversary’s nuclear weapons – or the nuclear command, control and communications systems necessary to manage them – to prevent nuclear retaliation.</p>
<p>Countries could point space-based weapons toward other regions of space, like the <a href="https://www.atlanticcouncil.org/blogs/new-atlanticist/russian-nuclear-anti-satellite-weapons-would-require-a-firm-us-response-not-hysteria/#:%7E:text=Nuclear%2Darmed%20ASATs%20would%20cause%20mass%20destruction&text=In%20part%20through%20the%20Space,satellite%20would%20be%20highly%20inefficient.">Russian weapon under development</a>. This conjures images of nuclear weapons <a href="https://ntrs.nasa.gov/api/citations/20205008370/downloads/Nuclear_Devices_for_Planetary_Defense_ASCEND_2020_FINAL_2020-10-02.pdf">striking asteroids to defend Earth</a> from a collision. </p>
<h2>Satellite killers</h2>
<p>The reality is less dramatic but no less worrisome. The most likely use would be to destroy an enemy’s military satellites. Damaging navigation satellites would hinder an adversary’s ability to fight a war. Both <a href="https://www.thedefensepost.com/2024/01/18/precision-strike-missile-seeker/">precision-strike</a> weapons and <a href="https://spacenews.com/u-s-military-doubles-down-on-gps-despite-vulnerabilities/">ground-based forces</a> rely on satellite constellations like GPS or the Russian <a href="https://gssc.esa.int/navipedia/index.php/GLONASS_General_Introduction">GLONASS</a> system to find and reach targets.</p>
<p>Countries may also want the ability to destroy an enemy’s space weapons, including space-based missile defenses. While no country has deployed these weapons yet, leaders may fear future capabilities and deploy space weapons first to hedge against this threat.</p>
<p>Most dangerously, these weapons could destroy or damage <a href="https://aerospace.csis.org/wp-content/uploads/2023/01/130223_MV_SpaceNuclearFinal.pdf">satellites critical</a> to an enemy’s <a href="https://www.airuniversity.af.edu/AUPress/Book-Reviews/Display/Article/3299649/nuclear-command-control-and-communications-a-primer-on-us-systems-and-future-ch/">nuclear command, control and communications system</a>, including early warning satellites that track missile launches and communication satellites that relay military orders.</p>
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<figcaption><span class="caption">The idea of attacking an enemy’s satellites has a long history.</span></figcaption>
</figure>
<p>Nuclear weapons damage satellites because of a <a href="https://www.osti.gov/biblio/6852629">wave of gamma radiation</a> that is created by a nuclear detonation. This radiation <a href="https://apps.dtic.mil/sti/tr/pdf/ADA531197.pdf">damages critical subsystems</a> within a satellite.</p>
<p>But such weapons produce significant drawbacks. A detonation would damage any satellites within range of the gamma radiation – including those of the attacking country, its allies and neutral countries.</p>
<p>However, a space-based nuclear anti-satellite weapon may have some advantages over other options for attacking countries. <a href="https://carnegieendowment.org/2021/11/17/dangerous-fallout-of-russia-s-anti-satellite-missile-test-pub-85804">Ground-based</a> <a href="https://www.tandfonline.com/doi/full/10.1080/14777622.2023.2277253">anti-satellite systems</a> <a href="https://www.airandspaceforces.com/russian-asat-test-underlines-need-for-defensive-space-tech/">can only reach targets</a> in low Earth orbit.</p>
<p>Even a nuclear-powered anti-satellite weapon in space would create <a href="https://www.youtube.com/watch?v=5A9izi9zFYI">a novel threat</a> without a nuclear warhead. Such a device would have a greater range than anti-satellite weapons on the ground and could perform its mission over an extended period of time. Both factors would increase the number of satellites it could damage or destroy.</p>
<p>Many of the satellites a country may want to take out are located at <a href="https://carnegieendowment.org/2021/12/16/protecting-valuables-establishing-keep-out-zones-around-high-altitude-satellites-pub-85964">higher orbits</a> beyond the range of ground-based systems. This is true for <a href="https://aerospace.csis.org/wp-content/uploads/2023/01/130223_MV_SpaceNuclearFinal.pdf">some of the U.S. systems</a> that Russia may want to target.</p>
<p>The Kremlin’s interest in space weapons could be an attempt to <a href="https://doi.org/10.1080/13523260.2022.2090070">reduce America’s capability to fight a war</a>; threaten nuclear command, control and communications systems; or hedge against space-based missile defenses. Alternatively, the Russian defense industry <a href="https://www.chathamhouse.org/2021/09/advanced-military-technology-russia/04-russian-space-systems-and-risk-weaponizing-space">may drive their development</a> for profit.</p>
<h2>New arms race?</h2>
<p>Whatever their initial purpose, placing nuclear weapons in space could be destabilizing. While there is not a universally accepted definition of strategic stability, scholars frequently <a href="https://www.amacad.org/publication/new-technologies-strategic-stability">define it as a combination</a> of crisis stability, based on the risk of nuclear escalation during a military crisis, and arms race stability – when countries can avoid <a href="https://doi.org/10.2307/2669307">actions and reactions that spiral</a> into a <a href="https://theconversation.com/the-nuclear-arms-races-legacy-at-home-toxic-contamination-staggering-cleanup-costs-and-a-culture-of-government-secrecy-210262">costly and dangerous</a> arms race.</p>
<p>Space-based nuclear weapons increase the risk that a country would resort to nuclear weapons during a crisis. Both weapons pointing toward Earth and those aimed at targets in space create incentives to use nuclear weapons preemptively. </p>
<p>The threat of either strike creates <a href="https://carnegieendowment.org/2018/08/08/escalation-through-entanglement-how-vulnerability-of-command-and-control-systems-raises-risks-of-inadvertent-nuclear-war-pub-77028">use-it-or-lose-it pressure</a>, <a href="http://dx.doi.org/10.26153/tsw/10220">incentivizing</a> a preemptive nuclear strike to limit the damage an adversary can do. In turn, a preemptive nuclear strike would likely <a href="https://thebulletin.org/2024/02/escalating-to-de-escalate-with-nuclear-weapons-research-shows-its-a-particularly-bad-idea/">provoke further escalation</a>, eventually ending in a total nuclear war.</p>
<p>Placing nuclear weapons in space could spark a new arms race. Because one purpose of space weapons is to destroy an adversary’s space weapons, the U.S. may respond to Russian weapons with their own. Russia may then counter with new weapons to maintain its advantage. Others, like China, may react to American weapons, which <a href="https://doi.org/10.1080/10736700.2015.1039309">could prompt a response</a> from India, followed by one from Pakistan.</p>
<p>Escalatory pressures and the threat of an arms race exist even if the first mover places weapons in space defensively. <a href="https://www.jstor.org/stable/26891884">Introducing space weapons</a> could create what <a href="https://doi.org/10.2307/2009187">international relations</a> <a href="https://www.jstor.org/stable/2009958">scholars</a> <a href="https://doi.org/10.1080/09636410903133050">call</a> a <a href="https://www.oxfordreference.com/display/10.1093/oi/authority.20110803100451770">security dilemma</a>: actions that enhance one country’s security but make another insecure.</p>
<p>Defensive and offensive weapons are <a href="https://doi.org/10.2307/2600696">often indistinguishable</a>. The weapons that could enhance one country’s security by hedging against space-based missile defense could also be used offensively against nuclear command, control and communications systems. Even if leaders in one country thought the other was acting defensively today, there is no way to know they will not act offensively tomorrow.</p><img src="https://counter.theconversation.com/content/223702/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Spenser A. Warren 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>Russia isn’t likely to put nuclear missiles in space, but their reported anti-satellite weapon is just as alarming. An expert on nuclear strategy explains.Spenser A. Warren, Postdoctoral Fellow in Technology and International Security, University of California, San DiegoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2156532024-02-11T13:50:28Z2024-02-11T13:50:28ZAn astronomer’s lament: Satellite megaconstellations are ruining space exploration<figure><img src="https://images.theconversation.com/files/574233/original/file-20240207-22-qbjsk9.jpg?ixlib=rb-1.1.0&rect=0%2C35%2C6000%2C3952&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Telescopes have to contend with light pollution from satellites.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>I used to love rocket launches when I was younger. During every launch, I imagined what it would feel like to be an astronaut sitting in the spacecraft, listening to that final countdown and then feeling multiple gees push me up through the atmosphere and away from our blue marble. </p>
<p>But as I learned more about the <a href="https://www.technologyreview.com/2018/06/22/142160/this-is-how-many-people-wed-have-to-send-to-proxima-centauri-to-make-sure-someone-actually/">severe limitations of human spaceflight</a>, I turned my attention to the oldest and most accessible form of space exploration: the science of astronomy.</p>
<p>Since 2019, I’ve watched my unencumbered enthusiasm for rocket launches soften to tepid interest, and finally sour to outright dread. <a href="https://globalnews.ca/news/9910084/the-new-space-race-2023/">The corporate space race</a>, led by SpaceX, is entirely responsible for this transformation in my mindset. </p>
<p>I am worried by the complete shift to the move-fast-and-break-things attitude that comes from the tech sector instead of government scientific agencies. I am put off by the <a href="https://press.uchicago.edu/ucp/books/book/chicago/A/bo184287883.html">colonialist language and billionaire-worship</a> of private corporations. I am increasingly furious at the <a href="https://www.startribune.com/string-lights-sky-not-ufo-starlink-satellite-internet/600324333/">nonexistent public education</a> and lack of transparency offered by these companies. </p>
<p>The final nail in the coffin for my love of rocket launches came with <a href="https://www.cnn.com/videos/business/2022/04/04/spacex-satellite-pollution-gothere-cnn-plus.cnn">SpaceX’s Starlink satellite megaconstellations</a>.</p>
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Read more:
<a href="https://theconversation.com/soon-1-out-of-every-15-points-of-light-in-the-sky-will-be-a-satellite-170427">Soon, 1 out of every 15 points of light in the sky will be a satellite</a>
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<h2>Crowded orbits</h2>
<p>The corporate space race is well underway, with private companies flooding Low Earth Orbit with <a href="https://planet4589.org/space/con/conlist.html">thousands of mass-produced satellites</a>. In previous decades, the prohibitively high cost of launch kept the rate of increase and total number of satellites from growing too rapidly. But launches have been getting steadily cheaper for years.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/OFfV33_eYPI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Al Jazeera reports on the impacts of Starlink satellites.</span></figcaption>
</figure>
<p>SpaceX has launched thousands of their own Starlink communication satellites, as well as hundreds of satellites for their direct competitors. <a href="https://www.illdefined.space/2023-global-space-activity-dashboards/">Half of all launches worldwide in 2023</a> were SpaceX rockets. </p>
<p>As an astronomer, I’m painfully aware of what these thousands of new satellites have done to the night sky worldwide. They reflect sunlight long after the sky has grown dark, looking like moving stars. </p>
<p>Starlink satellites are the most numerous and occupy some of the lowest orbits, so they make up the majority of the satellites seen in the sky. </p>
<p>Last year, SpaceX launched one of the <a href="https://doi.org/10.1038/s41586-023-06672-7">brightest objects in the sky</a> on behalf of another company: BlueWalker 3, a satellite with the same sky-footprint as a small house. They plan to operate a fleet of dozens, <a href="https://rdcu.be/drQOU">each as bright</a> as the brightest stars in the sky.</p>
<h2>Lost information and knowledge</h2>
<p>These satellites are now increasingly obstructing telescopic space exploration, <a href="https://www.nytimes.com/2024/01/09/science/astronomy-telescopes-satellites-spacex-starlink.html">both on the ground</a> and <a href="https://doi.org/10.1038/s41550-023-01903-3">in space</a>. Astronomers are the canaries in the coal mine for this rapidly expanding experiment in orbit: we see these satellites increasingly affecting our research every day.</p>
<p>I have watched over the past five years as satellite streaks in my own research images from the <a href="https://www.cfht.hawaii.edu/">Canada-France-Hawaii Telescope</a> have changed from an unusual occurrence to lost data in nearly every image.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a series of grey boxes with white streaks" src="https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=491&fit=crop&dpr=1 600w, https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=491&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=491&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=617&fit=crop&dpr=1 754w, https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=617&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/568276/original/file-20240108-25-vkyhs5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=617&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 composite of 29 individual exposures from the Canada-France-Hawaii Telescope on Maunakea, taken in August 2022. The horizontal and diagonal white lines are bright satellites that unexpectedly flew through the field of view during observations, covering any objects behind them.</span>
<span class="attribution"><span class="source">(P. Cowan/W. Fraser/S. Lawler/CLASSY Survey Team/CFHT)</span></span>
</figcaption>
</figure>
<p>Astronomy is the only way to learn about the universe, the overwhelming majority of which can never be explored by humans. The farthest human-made object from Earth is the <a href="https://voyager.jpl.nasa.gov/mission/status/">Voyager 1 probe</a>, now eight times farther from the sun than Neptune after 46 years continuously travelling significantly faster than a speeding bullet. </p>
<p>But even if Voyager 1 was pointed directly toward our nearest neighbouring star, Proxima Centauri (it’s not), it would take over 100,000 years to get there. We are light-years away from having technology that can robotically explore even our neighbouring solar systems on a human timescale, let alone bring humans out to the stars.</p>
<p>The vast majority of astronomy research is carried out by telescopes on Earth: large optical telescopes on remote mountaintops, large radio telescopes in radio-quiet zones that are meticulously maintained, as well as smaller telescopes scattered around the world.</p>
<p>There are a handful of telescopes in Low Earth Orbit that also have to <a href="https://skyandtelescope.org/astronomy-news/satellite-trails-mar-hubble-images/">contend with light pollution</a> from Starlink and other megaconstellations. There are also a <a href="https://webb.nasa.gov/content/about/orbit.html">handful of telescopes outside Earth orbit</a> which can only operate for a few years, unlike ground-based facilities that can be maintained and enhanced with new technologies for decades.</p>
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<a href="https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a large white dome looms against a dark sky" src="https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574239/original/file-20240207-28-qmjb00.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 Canada-Hawaii-France telescope, located on the summit of Mauna Kea, a dormant volcano located on the island of Hawaii.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Government regulation needed</h2>
<p>Space exploration using Earth-based telescopes is growing increasingly less effective as more bright and radio-loud satellites are placed between Earth and the stars. But there are much worse problems ahead if corporations continue launching satellites: atmospheric pollution on launch and <a href="https://doi.org/10.1073/pnas.2313374120">reentry</a>, ground casualty risks from <a href="https://doi.org/10.1038/s41550-022-01718-8">reentries</a>, and the very real possibility of a <a href="https://doi.org/10.1038/s41598-021-89909-7">runaway collisional cascade in orbit</a>, referred to as the Kessler Syndrome.</p>
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Read more:
<a href="https://theconversation.com/a-rapidly-growing-rocket-industry-could-undo-decades-of-work-to-save-the-ozone-layer-unless-we-act-now-198982">A rapidly growing rocket industry could undo decades of work to save the ozone layer – unless we act now</a>
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<p>Satellites are an incredibly useful part of our lives, but there are limits to how many can safely orbit Earth. Current regulations on launches and orbital operations by governments are very weak, and are not set up for the current regime of thousands of new satellites per year. </p>
<p>Regulation on the number of satellites in orbit would force corporations toward technology improvements and service models that use fewer satellites, keeping orbit usable for future generations.</p>
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Read more:
<a href="https://theconversation.com/its-not-too-late-to-save-the-night-sky-but-governments-need-to-get-serious-about-protecting-it-158394">It's not too late to save the night sky, but governments need to get serious about protecting it</a>
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<p>Ask your government representatives to support <a href="https://www.asc-csa.gc.ca/eng/transparency/consultations/what-we-heard-consulting-canadians-modern-regulatory-framework-space.asp">satellite regulation</a>, and expansion of <a href="https://crtc.gc.ca/eng/internet/internet.htm">rural broadband</a>. Get out and enjoy your <a href="https://www.cleardarksky.com/maps/lp/large_light_pollution_map.html">dark skies</a>, before they change. </p>
<p>With proper regulation, our oldest form of space exploration can continue. I desperately hope we never reach a point where the natural patterns in the sky are drowned out by anthropogenic ones, but without regulation, corporations will get us there soon.</p><img src="https://counter.theconversation.com/content/215653/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Samantha Lawler receives research funding from the Natural Sciences and Engineering Research Council of Canada.</span></em></p>Megaconstellations of satellites are hindering the most powerful tool for space exploration: telescopes.Samantha Lawler, Associate professor, Astronomy, University of ReginaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2198132023-12-14T23:35:58Z2023-12-14T23:35:58ZThe first-ever survey on Australian attitudes towards space is out. So, what do we think?<figure><img src="https://images.theconversation.com/files/565712/original/file-20231214-19-k3ard3.jpg?ixlib=rb-1.1.0&rect=103%2C54%2C3858%2C2647&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">NASA rocket launched from the Arnhem Space Centre in NT on June 26 2022.</span> <span class="attribution"><a class="source" href="https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=14164&button=recent">NASA Wallops/Brian Bonsteel</a></span></figcaption></figure><p>If someone were to ask you how space technologies impact your daily life, or how much Australia should invest in space, would you have an immediate answer or would you wonder why these questions were even being asked? </p>
<p>Understanding what the average Australian thinks about space is essential – voters and taxpayers will only encourage governments to fund space activities if they feel it is important. </p>
<p>Yet until now there was no comprehensive survey of Australian opinions about space in the 66 years since humans launched their first satellite in 1957.</p>
<p>Our new <a href="https://www.spacegovcentre.org/post/space-in-the-australian-public-eye-in-depth-survey-reveals-national-opinions">report</a> shows what the Australian public thinks about Australia’s investment and activities in space and the results are eye opening. </p>
<h2>Space tech is everywhere</h2>
<p>You’ve probably used space technologies <a href="https://www.youtube.com/watch?v=wrwJqdN6NF0">many times today</a> without thinking about it. This includes navigation apps on your phone, <a href="https://www.gps.gov/applications/timing/">paying for your coffee</a>, <a href="http://www.bom.gov.au/australia/satellite/about_satellites.shtml">checking the weather</a>, <a href="https://en.wikipedia.org/wiki/Satellite_Internet_access">high-speed internet</a> and maybe even remote health services. </p>
<p>Data and services from satellites underpin activities vital to our national economy. Space helps farmers predict when to harvest their crops and GPS ensures ships, planes and trucks reach their destinations. </p>
<p>Information from space also lets us investigate climate change, assists in predicting bushfires and helps emergency services respond to floods. Pictures from space contribute to Indigenous land and water management and protecting cultural heritage.</p>
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Read more:
<a href="https://theconversation.com/painting-with-fire-how-northern-australia-developed-one-of-the-worlds-best-bushfire-management-programs-205113">‘Painting with fire’: how northern Australia developed one of the world’s best bushfire management programs</a>
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<h2>What do Australians think about space?</h2>
<p>To understand what the public thinks about space today, the <a href="https://www.spacegovcentre.org/">Australian Centre for Space Governance</a> commissioned a study, co-funded by <a href="https://www.unsw.edu.au/canberra">UNSW Canberra</a>, which polled a nationally representative sample of more than 1,500 members of the Australian public. Our report is the first of its kind.</p>
<p>Our results showed the Australian community is interested in space but is unsure about what Australia does there. One third of Australians agreed space affected their everyday life and 44% were neutral. Around half of those surveyed are interested in Australian space activities but only a quarter said they were knowledgeable of global space events. </p>
<p>Similarly, the number of Australians who follow the activities of the <a href="https://www.space.gov.au/">Australian Space Agency</a>, established in 2018, was only around one fifth and an equal number had never heard of it. </p>
<p><iframe id="EdGzY" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/EdGzY/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>Australia has a long history of space activities, usually in cooperation with international partners. Australia has tested rockets at Woomera in South Australia and supported US Moon landings. This included providing broadcast images to the world of the Apollo 11 Moon landing in 1969. </p>
<p>But when asked to choose from a list including tracking stations and Australian-born astronauts, more Australians remembered the 2001 comedy <a href="https://en.wikipedia.org/wiki/The_Dish">The Dish</a> than any of Australia’s historic space activities.</p>
<p>In addition, only 16% of Australians were aware of the country’s first (and only) locally launched satellite, <a href="https://www.dst.defence.gov.au/innovation/wresat-%E2%80%94-weapons-research-establishment-satellite">WRESAT</a>, lofted into orbit on an American rocket from Woomera in 1967.</p>
<h2>How much should Australia spend on space?</h2>
<p>Space has also been a vital part of the country’s <a href="https://www.ussc.edu.au/the-evolution-of-the-australia-us-defence-space-relationship">defence forces</a> and a range of <a href="https://nsc.crawford.anu.edu.au/publication/18851/australia-space-power-combining-civil-defence-and-diplomatic-efforts">government functions</a> that support Australia’s security and resilience. Around 50% of Australians felt the Australian Defence Force should prioritise space alongside other areas of defence interest. </p>
<p>Many people are aware of important applications of Earth observation satellites, like weather forecasting, mapping, disaster response and climate data. However, less than a quarter disagreed with the <a href="https://www.abc.net.au/news/2023-06-29/labor-axes-morrison-government-satellite-program/102538686">cancellation</a> of the A$1.2 billion National Space Mission for Earth Observation, a proposed ongoing Earth observation satellite program. Of those surveyed, 45% were neutral and less than a quarter felt the mission should not have been cancelled.</p>
<p>Space missions also allow us to understand the universe. If you’ve ever looked at a picture sent back from a NASA probe, it’s highly likely the image was received at the <a href="https://www.csiro.au/en/about/facilities-collections/international-facilities/cdscc">tracking station</a> just outside of Canberra, managed by CSIRO. Nearly 55% of Australians think it is important to invest in space science, even if there is no immediate social or economic benefit.</p>
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<p>Overall, Australians are split about whether the country is spending the right amount on space. While 20% felt too little was spent on space technologies, 31% believed the amount was about right.</p>
<p>But the highest proportion, 36%, did not know. This is important, suggesting there isn’t sufficient information provided to the public. </p>
<h2>What do these results mean for Australia’s space future?</h2>
<p>Australians appear to be uncertain about the country’s space trajectory. But there were some clues about what direction the public feels Australia should take. Communication satellite technology and Earth observation were identified as the most important of the Australian Space Agency’s <a href="https://www.space.gov.au/Advancing%20Space%20Australian%20Civil%20Space%20Strategy%202019%20%E2%80%93%202028">seven priorities</a>. </p>
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<p>Australians also saw building satellite capability as an important focus. But developing local launch capabilities was rated as the lowest priority, despite this often being the focus of <a href="https://theconversation.com/nasa-to-launch-3-rockets-from-northern-territory-in-boost-for-australian-space-efforts-184646">media reporting</a>.</p>
<p>Importantly, respondents saw space as a useful way to encourage study and work in the sciences. They also believed space activities should include a diverse representation of the community. </p>
<p>The clearest insight from this report is Australians are interested in space but are not very aware of what we do in space and why. This reflects longstanding national debates about government spending on space technologies. </p>
<p>There is an opportunity to address this. Clear messaging of how space services contribute to individual lives, national needs and government priorities, will help inform decision making. </p>
<p>It will also ensure those decisions align with what the public wants and values. </p>
<hr>
<p><em>Correction: This article previously stated the wrong year for the Apollo 11 Moon landing. It has now been corrected to 1969.</em></p><img src="https://counter.theconversation.com/content/219813/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tristan Moss receives funding from the Australian Research Council as part of a Discovery Early Career Researcher Award and from UNSW Canberra. He has previously been funded by the Department of Defence and as a Fulbright Scholar. </span></em></p><p class="fine-print"><em><span>Aleksandar Deejay receives funding from Geoscience Australia. He is the Executive Director of the Australian Centre for Space Governance and a research fellow at the School of Regulation and Global Governance (RegNet).</span></em></p><p class="fine-print"><em><span>Cassandra Steer receives funding from Geoscience Australia, Home Affairs, Department of Defence, and has previously received funding from DFAT, the Australian Space Agency, and the Canadian and US Departments of Defence. She is Chair of the Australian Centre for Space Governance and is affiliated with the International Institute of Space Law.</span></em></p><p class="fine-print"><em><span>Kathryn Robison Hasani is a Senior Research Fellow at the Australian Centre for Space Governance. She is affiliated with Flinders University. </span></em></p>Despite what you may think, Australia has a long history of space activities. But this is the first time the Australian public has been asked its opinions on space.Tristan Moss, Senior lecturer, UNSW SydneyAleksandar Deejay, Research fellow, Australian National UniversityCassandra Steer, Deputy Director, Institute for Space (InSpace), Australian National UniversityKathryn Robison Hasani, Senior Research Fellow, Australian Centre for Space Governance, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2159792023-11-07T18:42:34Z2023-11-07T18:42:34ZOver the past six years, governments proposed launching over one million satellites, but where will they all go?<figure><img src="https://images.theconversation.com/files/557828/original/file-20231106-270141-rjcguo.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3840%2C2155&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">As the number of satellites in orbit increase, so will the possibilities of space debris. There are currently 8,000 satellites in orbit, but hundreds of thousands more are being proposed.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/over-the-past-six-years-governments-proposed-launching-over-one-million-satellites-but-where-will-they-all-go" width="100%" height="400"></iframe>
<p>In September 2021, Rwanda announced that it was <a href="https://spacenews.com/satellite-operators-criticize-extreme-megaconstellation-filings/">planning to launch over 300,000 satellites</a>. Three months later, a Canadian company, having previously launched two dozen <a href="https://www.asc-csa.gc.ca/eng/satellites/cubesat/what-is-a-cubesat.asp">CubeSats</a>, <a href="https://spacenews.com/kepler-plots-relay-network-to-serve-thousands-of-satellite-terminals/">said it would launch an additional 100,000</a>. Then, <a href="https://www.spaceintelreport.com/e-space-registers-116640-satellite-c-band-network-with-itu-through-france-300000-satellite-rwanda-network-is-no-more/">a French company did likewise</a>. And SpaceX, which has already launched <a href="https://planet4589.org/space/con/star/stats.html">around 5,000 satellites</a>, <a href="https://advanced-television.com/2023/10/12/spacex-applies-for-29988-new-satellites/">now has plans for over 60,000 more</a>. </p>
<p>There are currently only about <a href="https://www.ucsusa.org/resources/satellite-database">8,000 active satellites in orbit</a>. What’s going on?</p>
<p>Before a satellite is launched, a nation state must file its proposed satellite system with the <a href="https://www.itu.int/en/Pages/default.aspx">International Telecommunication Union</a> (ITU) to coordinate radiofrequency spectrum on behalf of the satellite operator, which could be a company, university or government agency. </p>
<p>These filings are made years ahead of the satellite launch, so the ITU can oversee coordination between different satellite operators and ensure that new satellite signals don’t drown existing ones out.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a corporate building" src="https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557888/original/file-20231106-17-ei62xl.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 UN International Telecommunication Union offices in Geneva, Switzerland.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>One million filings</h2>
<p><a href="https://doi.org/10.1126/science.adi4639">In a new Policy Forum article published in <em>Science</em></a>, we found that, between 2017 and 2022, countries collectively made filings for over one million satellites across more than 300 separate systems of multiple satellites working together, known as constellations.</p>
<p>This creates two intertwined problems. Either many of these satellites will actually be launched, <a href="https://doi.org/10.1016/j.actaastro.2020.01.016">causing an environmental crisis</a> through thousands of rocket launches into <a href="https://doi.org/10.1038/s41598-021-89909-7">increasingly crowded Earth orbits</a>, or operators are filing for more satellites than they intend to launch, perhaps with a view to hedging their bets, getting investor attention or selling the portions of radio spectrum for profit. </p>
<p>A closer look shows that the latter option is more likely.</p>
<h2>Congested orbits</h2>
<p>If even 10 per cent of the filed-for satellites launch, low Earth orbit would become congested with over 100,000 additional satellites. Collisions between satellites would generate space debris, which would in turn cause further collisions. </p>
<p>Reentering satellites would burn up in the atmosphere, <a href="https://phys.org/news/2023-10-signatures-space-age-spacecraft-metals.amp">potentially affecting the climate</a>, while surviving pieces of debris might strike people or aircraft. We already face these risks today, but they would increase by an order of magnitude.</p>
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Read more:
<a href="https://theconversation.com/airplanes-face-a-growing-risk-of-being-hit-by-uncontrolled-re-entries-of-rockets-used-to-launch-satellites-202400">Airplanes face a growing risk of being hit by uncontrolled re-entries of rockets used to launch satellites</a>
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<p>The problem may be more mundane, meaning that satellite operators are fiddling the numbers. Take E-Space, the French company. It is behind <a href="https://spacenews.com/wyler-raises-50-million-for-sustainable-megaconstellation/">both the 337,320-satellite constellation</a> filed through Rwanda in 2021, and a <a href="https://www.spaceintelreport.com/e-space-registers-116640-satellite-c-band-network-with-itu-through-france-300000-satellite-rwanda-network-is-no-more/">116,640-satellite constellation filed through France in 2023</a>. </p>
<p>Despite these ambitious filings, the company’s CEO, Greg Wyler, said it is planning for “<a href="https://youtu.be/1op-XeUUWMY?si=kKrb7TETXElsqwTV&t=491">at least 30,000 satellites</a>,” while its director of product development mentioned “<a href="https://www.spaceintelreport.com/e-space-registers-116640-satellite-c-band-network-with-itu-through-france-300000-satellite-rwanda-network-is-no-more/">just a few thousand satellites</a>.” Are any of these numbers real? </p>
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<a href="https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="photo of a night sky with blurred dots of light" src="https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557889/original/file-20231106-19-ni6o94.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">Starlink satellites passing over New Mexico.</span>
<span class="attribution"><a class="source" href="https://noirlab.edu/public/images/noirlab2206b/">(NOIRLab/M. Lewinsky)</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Countries of convenience</h2>
<p>There are more signs that companies are attempting to game the ITU system. </p>
<p>OneWeb, which has 634 satellites in orbit, has made filings for 6,118 more satellites through three countries: <a href="https://www.science.org/doi/10.1126/science.adi4639">Mexico, France and the United Kingdom</a>. </p>
<p>SpaceX has made filings through the <a href="https://www.science.org/doi/10.1126/science.adi4639">United States, Norway, Germany</a> and <a href="https://www.spaceintelreport.com/spacex-files-29988-satellite-w-band-network-using-kingdom-of-tonga-as-regulatory-home/">now Tonga</a>. It is unclear why this is happening, but all these states have different administrative rules — <a href="https://www.ofcom.org.uk/__data/assets/pdf_file/0028/256564/notice-of-satellite-filing-charges-2023-24.pdf">and fees</a> — associated with satellite filings. </p>
<p>In the global shipping industry, flag-of-convenience governments register ships for companies that seek lower operating costs through looser regulations and lax enforcement. Over <a href="https://unctadstat.unctad.org/CountryProfile/MaritimeProfile/en-GB/004/index.html">44 per cent of the world’s ships by tonnage</a> are registered in just three countries: Panama, Liberia and the Marshall Islands. These ships historically <a href="https://doi.org/10.1016/j.marpol.2018.10.026">have worse safety records and poorer labour conditions</a>. </p>
<p>Tonga, now home to <a href="https://www.spaceintelreport.com/spacex-files-29988-satellite-w-band-network-using-kingdom-of-tonga-as-regulatory-home/">SpaceX’s October 2023 filing for 29,998 satellites</a>, has filed for satellites before. In the 1980s, it <a href="https://www.nytimes.com/1990/08/28/business/tiny-tonga-seeks-satellite-empire-in-space.html">filed for 16 satellite slots</a>, eventually gaining nine slots which it promptly leased to foreign operators. </p>
<p>Other satellite operators weren’t happy; one even <a href="http://ojs-dev.byuh.edu/index.php/pacific/article/view/345/327">moved a satellite into one of Tonga’s slots in protest</a>. Yet Tonga made millions of dollars through the leases.</p>
<h2>Updating the rules</h2>
<p>The recent megaconstellation filings are of unprecedented size, raising multiple challenges. The ITU aims to prevent interference between satellites by modelling their signal power output, and the proliferation of satellites and the splitting of filings between different states are making that difficult. </p>
<p>The ITU — which is a United Nations agency that predates the UN, making it the oldest agency in the organization — has well-established processes for updating its rules. The 193 member states meet every three to four years at <a href="https://www.itu.int/en/ITU-R/conferences/wrc/Pages/default.aspx">World Radiocommunication Conferences</a>, where new rules are debated and adopted. </p>
<p>In 2019, member states agreed to <a href="https://www.itu.int/dms_pub/itu-r/opb/act/R-ACT-WRC.14-2019-PDF-E.pdf">create “milestones” for the deployment of satellite constellations</a>: launch 10 per cent of satellites within two years of the first launch, 50 per cent within five years and the whole constellation within seven years. However, the first satellite can be launched up to seven years after the filing, giving companies considerable time and flexibility.</p>
<p>The ITU should consider speeding up this process. It could also introduce fees that disincentivise large or speculative filings. </p>
<h2>Environmental responsibility</h2>
<p>The Secretary General of the ITU, Doreen Bogdan-Martin, has said <a href="https://spacenews.com/itu-emphasizes-importance-of-space-sustainability/">the ITU is increasingly prioritizing space sustainability</a>. But it must balance that goal with its mandate, which focuses on radio spectrum management.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CoFQscRtjec","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>From Nov. 20 to Dec. 15, 2023, the ITU member states will <a href="https://www.itu.int/wrc-23/">convene in Dubai</a> for this year’s World Radiocommunication Conference. But don’t expect radical changes this year; any proposals introduced now are unlikely to be finalised before the next conference in 2027. </p>
<p>And who knows what SpaceX, E-Space and other companies will get up to before then?</p><img src="https://counter.theconversation.com/content/215979/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>Countries have submitted applications for hundreds of thousands of new satellites to be launched. The scale poses challenges for overcrowding orbit, with environmental and safety challenges.Ewan Wright, PhD candidate, Interdisciplinary Studies, University of British ColumbiaAndrew Falle, Research Coordinator and Junior Fellow, Outer Space Institute, University of British ColumbiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2155452023-10-20T02:10:01Z2023-10-20T02:10:01ZSpace is getting crowded with satellites and space junk. How do we avoid collisions?<figure><img src="https://images.theconversation.com/files/554716/original/file-20231019-15-if092m.jpg?ixlib=rb-1.1.0&rect=882%2C1499%2C4543%2C3237&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://orbitaldebris.jsc.nasa.gov/photo-gallery/">NASA ODPO</a></span></figcaption></figure><p>Reports this week suggest <a>a near-collision</a> between an Australian satellite and a suspected Chinese military satellite.</p>
<p>Meanwhile, earlier this month, the US government issued the first ever space junk fine. The Federal Communications Commission <a href="https://www.fcc.gov/document/fcc-takes-first-space-debris-enforcement-action">handed a US$150,000 penalty</a> to the DISH Network, a publicly traded company providing satellite TV services. </p>
<p>It came as a surprise to many in the space industry, as the fine didn’t relate to any recent debris – it was issued for a communications satellite that has been in space for more than 21 years. It was <a href="https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2002-006A">EchoStar-7</a>, which failed to meet the orbit requirements outlined in a previously agreed debris mitigation plan.</p>
<p>The EchoStar-7 fine might be a US first, but it probably won’t be the last. We are entering an unprecedented era of space use and can expect the number of active <a href="https://time.com/6262389/space-junk-increasing-problem/#:%7E:text=The%20researchers%20report%20that%20there,launching%20all%20of%20that%20hardware.">satellites in space</a> to increase by 700% by the end of the decade.</p>
<p>As our local space gets more crowded, keeping an eye on tens of thousands of satellites and bits of space junk will only become more important. So researchers have a new field for this: space domain awareness.</p>
<h2>Three types of orbit, plus junk</h2>
<p>Humans have been launching satellites into space since 1957 and in the past 66 years have become rather good at it. There are currently <a href="https://orbit.ing-now.com">more than 8,700 active satellites</a> in various orbits around Earth.</p>
<p>Satellites tend to be in three main orbits, and understanding these is key to understanding the complex nature of space debris.</p>
<figure class="align-center ">
<img alt="An image of Earth with circles around it to indicate the distance of standard satellite orbits" src="https://images.theconversation.com/files/554715/original/file-20231019-29-mqpggf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/554715/original/file-20231019-29-mqpggf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=368&fit=crop&dpr=1 600w, https://images.theconversation.com/files/554715/original/file-20231019-29-mqpggf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=368&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/554715/original/file-20231019-29-mqpggf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=368&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/554715/original/file-20231019-29-mqpggf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=462&fit=crop&dpr=1 754w, https://images.theconversation.com/files/554715/original/file-20231019-29-mqpggf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=462&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/554715/original/file-20231019-29-mqpggf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=462&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Types of orbits around Earth classified by altitude (not to scale).</span>
<span class="attribution"><span class="source">Pexels/The Conversation</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The most common orbit for satellites is <a href="https://www.esa.int/ESA_Multimedia/Images/2020/03/Low_Earth_orbit">low Earth orbit</a>, with at least <a href="https://www.ucsusa.org/resources/satellite-database">5,900 active satellites</a>. Objects in low Earth orbit tend to reside up to 1,000km above Earth’s surface and are constantly on the move. The International Space Station is an example of a low Earth orbit object, travelling around Earth 16 times every day. </p>
<p>Higher up is the <a href="https://www.esa.int/Applications/Connectivity_and_Secure_Communications/Orbits">medium Earth orbit</a>, where satellites sit between 10,000 and 20,000km above Earth. It’s not a particularly busy place, but is home to some of the most important satellites ever launched – they provide us with the <a href="https://www.gps.gov/">global positioning system</a> or GPS.</p>
<p>Finally, we have very high altitude satellites in <a href="https://www.esa.int/Enabling_Support/Space_Transportation/Types_of_orbits#GEO">geosynchronous orbit</a>. In this orbit, satellites are upwards of 35,000km above Earth, in orbits that match the rate of Earth’s rotation. One special type of this orbit is a geostationary Earth orbit. It lies on the same plane as Earth’s equator, making the satellites appear stationary from the ground.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/6zoQmV3PGNc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Visualisation of The European Space Agency’s Space Debris Office statistics on space debris orbiting Earth (as of January 8 2021).</span></figcaption>
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<p>As you can tell, Earth’s surrounds are buzzing with satellite activity. It only gets more chaotic when we factor in <a href="https://www.nhm.ac.uk/discover/what-is-space-junk-and-why-is-it-a-problem.html">space junk</a>, defined as disused artificial debris in orbit around Earth.</p>
<p>Space junk can range from entire satellites that are no longer in use or working, down to millimetre-wide bits of spacecraft and launch vehicles left in orbit. <a href="https://www.esa.int/Space_Safety/Space_Debris/Space_debris_by_the_numbers">Latest estimates</a> suggest there are more than 130 million pieces of space debris, with only 35,000 of those large enough (greater than 10cm) to be routinely tracked from the ground. </p>
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<strong>
Read more:
<a href="https://theconversation.com/space-junk-in-earth-orbit-and-on-the-moon-will-increase-with-future-missions-but-nobodys-in-charge-of-cleaning-it-up-212421">Space junk in Earth orbit and on the Moon will increase with future missions − but nobody's in charge of cleaning it up</a>
</strong>
</em>
</p>
<hr>
<h2>How do we track them all?</h2>
<p>This is where space domain awareness comes in. It is the field of detecting, tracking and monitoring objects in Earth’s orbit, including active satellites and space debris.</p>
<p>We do much of this with ground-based tracking, either through radar or optical systems like telescopes. While radar can easily track objects in low Earth orbit, higher up we need optical sensors. Objects in medium Earth orbit and geostationary orbit can be tracked using sunlight reflected towards Earth.</p>
<p>For reliable and continuous space domain awareness, we need multiple sensors contributing to this around the globe.</p>
<p>Below you can see what high-altitude satellites can look like to telescopes on Earth, appearing to stay still as the stars move by. </p>
<figure>
<iframe src="https://player.vimeo.com/video/848579076" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
<figcaption><span class="caption">Tracking two Optus satellites 16km apart, using EOS’ 0.7m deep space telescope at Learmonth, Western Australia. Source: EOS - Electro Optic Systems.</span></figcaption>
</figure>
<h2>Australia’s role in space awareness</h2>
<p>Thanks to our position on Earth, Australia has a unique opportunity to contribute to space domain awareness. The US already houses several facilities on the west coast of Australia as part of the <a href="https://nsarchive.gwu.edu/briefing-book/intelligence/2023-03-13/whats-there-where-it-and-whats-it-doing-us-space-surveillance">Space Surveillance Network</a>. That’s because on the west coast, telescopes can work in dark night skies with minimal light pollution from large cities.</p>
<p>Furthermore, we are currently working on a <a href="https://www.cgi.com/au/en-au/news/space/cgi-rmit-and-swinburne-university-technology-enhance-australian-space-domain-awareness">space domain awareness technology demonstrator</a> (a proof of concept), funded by <a href="https://smartsatcrc.com">SmartSat CRC</a>. This is a government-funded consortium of universities and other research organisations, along with industry partners such as the IT firm CGI.</p>
<p>We are combining our expertise in observational astrophysics, advanced data visualisation, artificial intelligence and space weather. Our goal is to have technology that understands what is happening in space minute-by-minute. Then, we can line up follow-up observations and monitor the objects in orbit. Our team is currently working on geosynchronous orbit objects, which includes active and inactive satellites. </p>
<p>EchoStar-7 was just one example of the fate of a retired spacecraft – the FCC is sending a strong warning to all other companies to ensure their debris mitigation plans are met.</p>
<p>Inactive objects in orbit could pose a collision risk to each other, leading to a rapid increase in space debris. If we want to use Earth’s space domain for as long as possible, we need to keep it safe for all.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/harpoons-robots-and-lasers-how-to-capture-defunct-satellites-and-other-space-junk-and-bring-it-back-to-earth-189698">Harpoons, robots and lasers: how to capture defunct satellites and other space junk and bring it back to Earth</a>
</strong>
</em>
</p>
<hr>
<p><em>Acknowledgment: The authors would like to thank Sholto Forbes-Spyratos, military space lead at CGI Space, Defence and Intelligence Australia, for his contribution to this article.</em></p><img src="https://counter.theconversation.com/content/215545/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sara Webb receives funding through a research project co-funded by CGI technologies and SmartSat CRC, on work related to space domain awareness. She is a member of the Astronomical Society of Australia and American Society for Gravitational and Space Research. </span></em></p><p class="fine-print"><em><span>Brett Carter is an Editor of the American Geophysical Union journal Space Weather. He receives funding from the Australian Research Council, SmartSat CRC and FrontierSI. He is also a member of the Australian Institute of Physics and the American Geophysical Union.</span></em></p><p class="fine-print"><em><span>Christopher Fluke works for Swinburne University of Technology. He receives funding from the SmartSat CRC, including funding to support a research collaboration with CGI and RMIT. He is a member of the Astronomical Society of Australia and the International Astronomical Union.</span></em></p>Earth’s orbits are getting more and more crowded. To keep track of everything and avoid collisions and catastrophes, we need a new field: space domain awareness.Sara Webb, Postdoctoral Research Fellow, Centre for Astrophysics and Supercomputing, Swinburne University of TechnologyBrett Carter, Associate Professor, RMIT UniversityChristopher Fluke, SmartSat Professorial Chair, Swinburne University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2152502023-10-13T04:04:14Z2023-10-13T04:04:14ZStarlink satellites are ‘leaking’ signals that interfere with our most sensitive radio telescopes<figure><img src="https://images.theconversation.com/files/553608/original/file-20231013-27-sjapd4.jpeg?ixlib=rb-1.1.0&rect=17%2C29%2C3976%2C2628&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://noirlab.edu/public/images/ann21021c/">NOIRLab</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>When I was a child in the 1970s, seeing a satellite pass overhead in the night sky was a rare event. Now it is commonplace: sit outside for a few minutes after dark, and you can’t miss them.</p>
<p>Thousands of satellites have been launched into Earth orbit over the past decade or so, with tens of thousands more <a href="https://planet4589.org/space/con/conlist.html">planned</a> in coming years. Many of these will be in “mega-constellations” such as Starlink, which aim to cover the entire globe.</p>
<p>These bright, shiny satellites are putting at risk our connection to the cosmos, which has been important to humans for countless millennia and has already been <a href="https://education.nationalgeographic.org/resource/light-pollution/">greatly diminished</a> by the growth of cities and artificial lighting. They are also posing a problem for astronomers – and hence for our understanding of the universe.</p>
<p>In <a href="https://arxiv.org/abs/2309.15672">new research</a> accepted for publication in Astronomy and Astrophysics Letters, we discovered Starlink satellites are also “leaking” radio signals that interfere with radio astronomy. Even in a “<a href="https://www.industry.gov.au/science-technology-and-innovation/space-and-astronomy/co-hosting-ska-telescope/australian-radio-quiet-zone-wa">radio quiet zone</a>” in outback Western Australia, we found the satellite emissions were far brighter than any natural source in the sky. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/0Aj2lmQBSAg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">An animation showing the increase in the number of satellites in Earth orbit, over the course of the space age, so far.</span></figcaption>
</figure>
<h2>A problem for our understanding of the universe</h2>
<p>Our team at Curtin University used <a href="https://arxiv.org/abs/2112.00908?context=astro-ph">radio telescopes in Western Australia</a> to examine the radio signals coming from satellites. </p>
<p>We found expected radio transmissions at designated and licensed radio frequencies, used for communication with Earth. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/TT1hJ2NOZQo?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Starlink satellites emit bright flashes of radio transmission (shown in blue) at their allocated frequency of 137.5 MHz.</span></figcaption>
</figure>
<p>However, we also found signals at unexpected and unintended frequencies. </p>
<p>We found these signals coming from many Starlink satellites. It appears the signals may originate from electronics on board the spacecraft.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/FISUgjrCAi4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Here we see constant, bright emissions from Starlink satellites at 159.4 MHz, a frequency not allocated to satellite communications.</span></figcaption>
</figure>
<p>Why is this an issue? Radio telescopes are incredibly sensitive, to pick up faint signals from countless light-years away. </p>
<p>Even an extremely weak radio transmitter hundreds or thousands of kilometres away from the telescope appears as bright as the most powerful cosmic radio sources we see in the sky. So these signals represent a serious source of interference.</p>
<p>And specifically, the signals are an issue at the location where we tested them: the <a href="https://www.csiro.au/en/about/facilities-collections/atnf/mro">site in WA</a> where construction has already begun for part of the biggest radio observatory ever conceived, the <a href="http://www.skatelescope.org">Square Kilometre Array</a> (SKA). This project involves 16 countries, has been in progress for 30 years, and will cost billions of dollars over the next decade.</p>
<p>Huge effort and expense has been invested in locating the SKA and other astronomy facilities a long way away from humans. But satellites present a new threat in space, which can’t be dodged.</p>
<h2>What can we do about this?</h2>
<p>It’s important to note satellite operators do not appear to be breaking any rules. The regulations around use of the radio spectrum are governed by the <a href="https://www.itu.int/pub/R-HDB-22-2013">International Telecommunications Union</a>, and they are complex. At this point there is no evidence Starlink operators are doing anything wrong.</p>
<p>The radio spectrum is crucial for big business and modern life. Think mobile phones, wifi, GPS and aircraft navigation, and communications between Earth and space. </p>
<p>However, the undoubted benefits of space-based communications – such as for globally accessible fast internet connections – are coming into conflict with our ability to see and explore the universe. (There is some irony here, as wifi in part owes its <a href="https://en.wikipedia.org/wiki/Wi-Fi">origins</a> to radio astronomy.)</p>
<p>Regulations evolve slowly, while the technologies driving satellite constellations like Starlink are developing at lightning speed. So regulations are not likely to protect astronomy in the near term.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-many-satellites-are-orbiting-earth-166715">How many satellites are orbiting Earth?</a>
</strong>
</em>
</p>
<hr>
<p>But in the course of our research, we have had a very positive engagement with SpaceX engineers who work on the Starlink satellites. It is likely that the goodwill of satellite operators, and their willingness to mitigate the generation of these signals, is the key to solving the issue.</p>
<p>In response to earlier criticisms, SpaceX has made <a href="https://arxiv.org/abs/2306.06657">improvements</a> to the amount of sunlight Starlink satellites reflect, making them one-twelfth as bright in visible light as they used to be.</p>
<p>We estimate emissions in radio wavelengths will need to be reduced by a factor of a thousand or more to avoid significant interference with radio astronomy. We hope these improvements can be made, in order to preserve humanity’s future view of the universe, the fundamental discoveries we will make, and the future society-changing technologies (like wifi) that will emerge from those discoveries.</p><img src="https://counter.theconversation.com/content/215250/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steven Tingay is affiliated with the Australian Labor Party. </span></em></p>Starlink satellites emit bright, unintended and unexpected signals that can be detected by radio telescopes.Steven Tingay, John Curtin Distinguished Professor (Radio Astronomy), Curtin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2094922023-09-05T12:32:22Z2023-09-05T12:32:22ZWhat is geospatial intelligence? A geographer explains the powerful melding of maps and data<figure><img src="https://images.theconversation.com/files/545837/original/file-20230831-29-uaz7h6.jpg?ixlib=rb-1.1.0&rect=0%2C8%2C6000%2C3979&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Where + what = geospatial intelligence.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/august-2020-hanover-geospatial-information-provides-an-news-photo/1556978824">Peter Steffen/picture alliance via Getty Images</a></span></figcaption></figure><p>With <a href="https://theconversation.com/july-was-earths-hottest-month-on-record-4-factors-driving-2023s-extreme-heat-and-climate-disasters-209975">record-breaking temperatures</a> across the South, <a href="https://theconversation.com/wildfire-smoke-and-dirty-air-are-also-climate-change-problems-solutions-for-a-world-on-fire-207676">smoke from Canadian wildfires</a> across the North, <a href="https://theconversation.com/how-climate-change-intensifies-the-water-cycle-fueling-extreme-rainfall-and-flooding-the-northeast-deluge-was-just-the-latest-209476">historic flooding</a> in the Northeast and a <a href="https://theconversation.com/hurricane-idalia-intensifies-over-extremely-warm-gulf-waters-on-track-for-florida-landfall-as-a-dangerous-major-hurricane-212410">powerful hurricane in the Southeast</a>, the <a href="https://www.usatoday.com/story/news/nation/2023/07/01/smoke-heat-wave-forecast-for-summer-2023-is-looking-bad-experts-say/70364826007/">summer of 2023</a> has presented a range of threats to the safety of the majority of Americans. The good news, through all of this: <a href="https://www.nga.mil/resources/GEOINT_Basic_Doctrine_Publication_10_.html">Geospatial intelligence</a> has offered valuable insights to help governments and organizations protect communities.</p>
<p>Geospatial intelligence is the collection and integration of data from a network of technologies, including satellites, mobile sensors, ground-control stations and aerial images. The data is used to produce <a href="https://trajectorymagazine.com/no-matter-their-scale-nga-maps-have-huge-impact/">real-time maps</a> and simulations to help identify when, where and to what extent a threat is likely to emerge. Government officials, individuals or both can use this information to <a href="https://www.nga.mil/about/Mission.html">make informed decisions</a>.</p>
<h2>Disasters sudden and slow</h2>
<p>One long-standing contribution of geospatial intelligence is in emergency preparedness and response. For example, the <a href="https://www.nhc.noaa.gov/">National Hurricane Center</a> actively monitors the location, formation and trajectory of tropical cyclones. Detailed information on the timing, location and strength of a given hurricane helps officials distribute resources and personnel, as well as issue storm warnings and evacuation orders. </p>
<p>Geospatial intelligence also provides valuable guidance for search-and-rescue and recovery efforts following a disaster. For example, in the immediate aftermath of the February 2023 7.8 magnitude <a href="https://www.unicef.org/emergencies/Syria-Turkiye-earthquake">earthquake that struck Turkey and Syria</a>, maps and aerial images quickly identified the extent of damage and the populations affected. In addition, they helped first responders locate access points in the transportation network to rescue survivors, set up aid stations and provide emergency supplies.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C1868%2C972&q=45&auto=format&w=1000&fit=clip"><img alt="A map of the United States overlaid by colored blobs" src="https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C1868%2C972&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=312&fit=crop&dpr=1 600w, https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=312&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=312&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=392&fit=crop&dpr=1 754w, https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=392&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/542416/original/file-20230811-15-lh0j6x.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=392&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 Environmental Protection Agency publishes air quality maps that are particularly useful when smoke from wildfires spreads across large parts of the U.S.</span>
<span class="attribution"><a class="source" href="https://gispub.epa.gov/airnow/?tab=archive&archivedates=06%2F01%2F2023&xmin=-19900762.26273924&xmax=-1614579.1120248176&ymin=546395.5542774848&ymax=8725769.07701545">EPA</a></span>
</figcaption>
</figure>
<p>Another use of geospatial intelligence is environmental monitoring. A stable environment is essential for human health and security. Monitoring temperature, precipitation, <a href="https://nsidc.org/home">snowpack and polar ice</a> helps scientists and government officials anticipate and prepare for potential disturbances.</p>
<p>For instance, understanding <a href="https://www.severe-weather.eu/long-range-2/summer-2023-weather-forecast-update-el-nino-rising-atmosphere-pattern-shift-united-states-europe-fa/">temperature profiles</a> – past, current and forecasted temperatures over an area – provides information on when, where and to what extent that area is likely to be affected by events such as heat waves. Heat waves often result in <a href="https://theconversation.com/if-you-thought-this-summers-heat-waves-were-bad-a-new-study-has-some-disturbing-news-about-dangerous-heat-in-the-future-189370">human suffering</a>, <a href="https://theconversation.com/4-ways-extreme-heat-hurts-the-economy-164382">increased energy demands and crop damage</a>. With climate change intensifying extreme weather events, there is likely to be a corresponding increase in threats to human safety and security.</p>
<h2>Military and civilian logistics</h2>
<p>The Russian-Ukraine war is another area where geospatial intelligence has made contributions. Maxar Technologies, a commercial satellite imagery company, was the first to report the 40-mile-long <a href="https://blog.maxar.com/earth-intelligence/2023/new-documentary-on-ukraine-underscores-the-importance-of-maxars-commercial-satellite-imagery-and-capabilities">convoy of Russian ground forces</a> heading toward Kyiv in February 2022.</p>
<p>While governments historically could choose whether to release intelligence-related information, commercial satellite companies now play a vital role in providing this type of information to the public. In this way, geospatial intelligence represents an extension of the free press.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Ce3rDcCophY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Geospatial intelligence is a key component of open-source intelligence, which in turn has played a key role in monitoring the war in Ukraine.</span></figcaption>
</figure>
<p>Another use of geospatial intelligence is in <a href="https://doi.org/10.1007/978-981-15-5720-0_6">transportation, logistics and global supply chains</a>. The global economy runs on GPS, which generates spatial data. GPS provides governments, businesses and people with detailed information on the time, location and destination of ships and cargo. This leads to greater efficiency and more consistent and reliable operations.</p>
<p>Geospatial intelligence is also helping with the <a href="https://doi.org/10.22381/CRLSJ13220217">rollout of autonomous vehicles</a>. Using high-resolution imagery of about a foot (30 cm) per pixel, city planners and engineers are able to detect markings and features on the ground such as bicycle lanes and traffic direction. These advances help planners build safer, smarter, more efficient and better connected communities.</p>
<p>Yet another use of geospatial intelligence is contributing to the development, implementation and evaluation of <a href="https://theconversation.com/what-are-digital-twins-a-pair-of-computer-modeling-experts-explain-181829">digital twins</a>. Digital twins are virtual representations of real systems – buildings or cities, for example – that mimic the systems’ characteristics and can be updated in real time to reflect changing conditions in the systems.</p>
<p>Digital twins are being used in many civilian and military settings to improve decision making. They are useful for modeling changes and predicting outcomes. Digital twins have been highly effective in conflict settings by <a href="https://trajectorymagazine.com/rapid-terrain-generation/">simulating weather and terrain</a> to help militaries and peacekeepers develop and enact strategies.</p>
<h2>Growing need</h2>
<p>The need for geospatial intelligence is more important than ever. Average temperature is projected to <a href="https://www.climate.gov/news-features/understanding-climate/climate-change-global-temperature-projections">increase between 2 to 9.7 degrees Fahrenheit (1.1 to 5.4 degrees Celsius)</a> by the end of the century. The global population is expected to reach <a href="https://www.un.org/en/global-issues/population">11 billion by 2100</a>, and urban areas are becoming denser and more prone to disasters. Whether reconstructing the past, describing the present or anticipating the future, geospatial intelligence provides valuable information to help keep people and communities safe.</p>
<p>Not surprisingly, the geospatial intelligence industry is projected to grow from a US$61 billion enterprise in 2020 <a href="https://usgif.org/geoint-symposium-2023/">to more than $209 billion in 2030</a>. The world is rapidly transforming, and geospatial intelligence is positioned to play an increasingly important role in <a href="https://trajectorymagazine.com/geospatial-intelligence-revolution-in-insurance-and-risk-management/">working toward a safe, stable and informed future</a>.</p><img src="https://counter.theconversation.com/content/209492/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Darren Ruddell 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 combination of data and maps is useful for a lot more than just helping you get from point A to point B. Think natural disasters, global supply chains and climate change.Darren Ruddell, Associate Professor of Spatial Sciences, University of Southern CaliforniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2124212023-08-31T12:23:19Z2023-08-31T12:23:19ZSpace junk in Earth orbit and on the Moon will increase with future missions − but nobody’s in charge of cleaning it up<figure><img src="https://images.theconversation.com/files/545374/original/file-20230829-25-ksnt5w.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4500%2C2627&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An artist's rendering of debris floating through Earth's orbit. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/garbage-royalty-free-image/474381690?phrase=space+junk&adppopup=true">Petrovich9/iStock via Getty Images</a></span></figcaption></figure><p>There’s a lot of trash on the Moon right now – including nearly <a href="https://www.vox.com/science-and-health/2019/3/22/18236125/apollo-moon-poop-mars-science">100 bags of human waste</a> – and with countries around the globe traveling <a href="https://theconversation.com/returning-to-the-moon-can-benefit-commercial-military-and-political-sectors-a-space-policy-expert-explains-209300">to the Moon</a>, there’s going to be a lot more, both on the lunar surface and in Earth’s orbit.</p>
<p>In August 2023, Russia’s <a href="https://theconversation.com/russia-has-declared-a-new-space-race-hoping-to-join-forces-with-china-heres-why-thats-unlikely-211993">Luna-25</a> probe crashed into the Moon’s surface, while India’s <a href="https://theconversation.com/indias-chandrayaan-3-landed-on-the-south-pole-of-the-moon-a-space-policy-expert-explains-what-this-means-for-india-and-the-global-race-to-the-moon-212171">Chandrayann-3</a> mission successfully landed in the southern polar region, making India the fourth country to land on the Moon.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A group of cheering, smiling people hold signs depicting the Chandrayaan-3 lander." src="https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=411&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=411&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=411&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=516&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=516&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545376/original/file-20230829-16-rsr2b4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=516&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">India’s Chandrayaan-3 lander successfully touched down on the south pole of the Moon, sparking celebrations across the country.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/IndiaLunarMission/ac52e7da7b46474a91706ffa43f7c99a/photo?Query=india%20moon%20landing&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=89&currentItemNo=24">AP Photo/Rajanish Kakade</a></span>
</figcaption>
</figure>
<p>With more countries landing on the Moon, people back on Earth will have to think about what happens to all the landers, waste and miscellaneous debris left on the lunar surface and in orbit.</p>
<p>I’m a professor of astronomy who has written a book about the <a href="https://wwnorton.com/books/Beyond/">future of space travel</a>, articles about <a href="https://zenodo.org/record/1477986">our future off-Earth</a>, <a href="https://thehill.com/opinion/international/575903-is-conflict-in-space-inevitable">conflict in space</a>, <a href="https://thehill.com/opinion/national-security/3263430-space-an-increasingly-contested-and-congested-frontier/">space congestion</a> and the <a href="https://doi.org/10.2478/sh-2021-0020">ethics of space exploration</a>. Like many other space experts, I’m concerned about the lack of governance around space debris.</p>
<h2>Space is getting crowded</h2>
<p>People think of space as vast and empty, but the near-Earth environment is starting to get crowded. As many as <a href="https://thenationaldigest.com/up-to-100-space-missions-to-the-moon-to-take-place-in-the-next-decade/">100 lunar missions</a> are planned over the next decade by governments and private companies like SpaceX and Blue Origin. </p>
<p>Near-Earth orbit is even more congested than the space between Earth and the Moon. It’s from 100 to 500 miles straight up, compared with 240,000 miles to the Moon. Currently there are nearly <a href="https://orbit.ing-now.com/low-earth-orbit/">7,700 satellites</a> within a few hundred miles of the Earth. <a href="https://theconversation.com/how-many-satellites-are-orbiting-earth-166715">That number</a> could grow to <a href="https://doi.org/10.1063/PT.3.4979">several hundred thousand</a> by 2027. Many of these satellites will be used to deliver internet to developing countries or to <a href="https://theconversation.com/landsat-turns-50-how-satellites-revolutionized-the-way-we-see-and-protect-the-natural-world-186986">monitor agriculture</a> and <a href="https://theconversation.com/how-to-use-free-satellite-data-to-monitor-natural-disasters-and-environmental-changes-198140">climate</a> on Earth. Companies like SpaceX have dramatically <a href="https://theconversation.com/how-spacex-lowered-costs-and-reduced-barriers-to-space-112586">lowered launch costs</a>, driving this wave of activity.</p>
<p>“It’s going to be like an interstate highway, at rush hour in a snowstorm, with everyone driving much too fast,” space launch expert <a href="https://scholar.google.com/citations?user=OEsqBIsAAAAJ&hl=en">Johnathan McDowell</a> <a href="https://www.space.com/how-many-satellites-fit-safely-earth-orbit">told Space.com</a>. </p>
<h2>The problem of space junk</h2>
<p>All this activity creates hazards and debris. Humans have left a lot of junk on the Moon, including spacecraft remains like rocket boosters from over <a href="https://doi.org/10.1038/d41586-022-00542-4">50 crashed landings</a>, nearly <a href="https://www.vox.com/science-and-health/2019/3/22/18236125/apollo-moon-poop-mars-science">100 bags of human waste</a> and miscellaneous objects like a feather, golf balls and boots. It adds up to around <a href="https://www.theatlantic.com/technology/archive/2012/12/the-trash-weve-left-on-the-moon/266465/">200 tons of our trash</a>. </p>
<p>Since <a href="https://theconversation.com/who-owns-the-moon-a-space-lawyer-answers-99974">no one owns the Moon</a>, no one is responsible for <a href="https://www.vox.com/science/2023/8/24/23844280/india-moon-landing-russia-crash-lunar-south-pole-science-consequences-junk">keeping it clean and tidy</a>. </p>
<p>The <a href="https://www.space.com/space-junk-growing-problem-complicated-solution">clutter in Earth’s orbit</a> includes defunct spacecraft, spent rocket boosters and items discarded by astronauts such as a glove, a wrench and a toothbrush. It also includes <a href="https://www.nasa.gov/mission_pages/station/news/orbital_debris.html">tiny pieces of debris</a> like paint flecks. </p>
<p>There are around 23,000 <a href="https://www.nasa.gov/mission_pages/station/news/orbital_debris.html">objects</a> larger than 10 cm (4 inches) and about 100 million pieces of debris larger than 1 mm (0.04 inches). Tiny pieces of junk might not seem like a big issue, but that debris is moving at 15,000 mph (24,140 kph), 10 times faster than a bullet. <a href="https://www.space.com/tiny-space-junk-damage">At that speed</a>, even a fleck of paint can puncture a spacesuit or destroy a sensitive piece of electronics.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/0Aj2lmQBSAg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The amount of debris in orbit has increased dramatically since the 1960s.</span></figcaption>
</figure>
<p>In 1978, NASA scientist <a href="https://www.britannica.com/biography/Donald-Kessler">Donald Kessler</a> described a scenario where collisions between orbiting pieces of debris create more debris, and the amount of debris grows exponentially, potentially rendering near-Earth orbit unusable. Experts call this the “<a href="https://www.techtarget.com/whatis/definition/Kessler-Syndrome">Kessler syndrome</a>.” </p>
<h2>Nobody is in charge up there</h2>
<p>The United Nations <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introouterspacetreaty.html">Outer Space Treaty of 1967</a> says that no country can “own” the Moon or any part of it, and that celestial bodies should only be used for peaceful purposes. But the treaty is mute about companies and individuals, and it says nothing about how space resources can and can’t be used. </p>
<p>The United Nations <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/intromoon-agreement.html">Moon Agreement of 1979</a> held that the Moon and its natural resources are the common heritage of humanity. However, the United States, Russia and China never signed it, and in 2016 the <a href="https://www.congress.gov/bill/114th-congress/house-bill/2262/text">U.S. Congress created a law</a> that unleashed the American commercial space industry with very few restrictions. </p>
<p>Because of its lack of regulation, space junk is an example of a “<a href="https://carnegieendowment.org/2021/03/09/space-is-great-commons.-it-s-time-to-treat-it-as-such-pub-84018">tragedy of the commons</a>,” where many interests have access to a common resource, and it may become depleted and unusable to everyone, because no interest can stop another from overexploiting the resource.</p>
<p>Scientists argue that to avoid a tragedy of the commons, the orbital space environment should be seen as a <a href="https://doi.org/10.1038/s41550-022-01655-6">global commons</a> worthy of protection by the <a href="https://hir.harvard.edu/the-uns-role-in-planetary-protection/">United Nations</a>. The lead author of a <a href="https://doi.org/10.1038/s41550-022-01655-6">Nature article</a> arguing for a global commons filed an <a href="https://andyxlastro.me/wp-content/uploads/2021/08/Amicus-Brief-Lawrence.pdf">amicus brief</a> – a type of outside comment offering support or expertise – on a case that went to the <a href="https://docs.fcc.gov/public/attachments/DOC-386646A1.pdf">U.S. Court of Appeals for the District of Columbia Circuit</a> in late 2021.</p>
<p>The author and his research collaborators argued that U.S. environmental regulations should apply to the licensing of space launches. However, the court declined to rule on the environmental issue because it said the group lacked standing.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/jSuETYEgY68?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The tragedy of the commons asserts that if everyone has unlimited access to a resource, then in the long run it may become depleted and unusable.</span></figcaption>
</figure>
<p>National geopolitical and commercial interests will likely take precedence over interplanetary conservation efforts unless the United Nations acts. A new treaty may emerge from the work of the U.N. <a href="https://www.unoosa.org/">Office for Outer Space Affairs</a>, which in May 2023 generated a <a href="https://indonesia.un.org/sites/default/files/2023-07/our-common-agenda-policy-brief-outer-space-en.pdf">policy document</a> to address the sustainable development of activities in space.</p>
<p>The U.N. can regulate the activities of only its member states, but it has a <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/capacitybuilding/advisory-services/index.html">project</a> to help member states craft national-level policies that advance the goals of sustainable development.</p>
<p>NASA has created and signed the <a href="https://www.nasa.gov/specials/artemis-accords/index.html">Artemis Accords</a>, broad but nonbinding principles for cooperating peacefully in space. They have been signed by 28 countries, but the list does not include China or Russia. <a href="https://mashable.com/article/who-owns-moon-resources-nasa-artemis">Private companies</a> are not party to the accords either, and some <a href="https://www.axios.com/2021/07/13/branson-bezos-space-travel-billionaires-nasa">space entrepreneurs</a> have deep pockets and big ambitions.</p>
<p>The lack of regulation and the current gold rush approach to space exploration mean that space junk and waste will continue to accumulate, as will the related problems and dangers.</p><img src="https://counter.theconversation.com/content/212421/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>Treaties meant to ensure sustainability in space don’t currently regulate private companies, and not every country has signed on to an agreement for sustainable space exploration.Chris Impey, University Distinguished Professor of Astronomy, University of ArizonaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2102632023-08-30T12:15:57Z2023-08-30T12:15:57ZGiraffes range across diverse African habitats − we’re using GPS, satellites and statistics to track and protect them<figure><img src="https://images.theconversation.com/files/544746/original/file-20230825-17-am7gat.jpeg?ixlib=rb-1.1.0&rect=11%2C0%2C3768%2C2345&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An average giraffe has a home range almost as large as Philadelphia.</span> <span class="attribution"><span class="source">Michael Brown</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>Nearly 6,000 years ago, our ancestors climbed arid rocky outcrops in what is now the Nigerian Sahara and carved spectacularly intricate, larger-than-life renditions of giraffes into the exposed sandstone. The remarkably detailed Dabous giraffe rock art petroglyphs are among <a href="https://journals.co.za/doi/pdf/10.10520/AJA00382353_1067">many ancient petroglyphs featuring giraffes across Africa</a> – a testament to early humans’ fascination with these unique creatures. </p>
<p>We are still <a href="https://doi.org/10.1371/journal.pone.0199149">captivated by giraffes today</a>, but many of these animals are at risk, largely due to habitat loss and illegal hunting. Some <a href="https://giraffeconservation.org/programmes/giraffe-conservation-status-assessment/">are critically endangered</a>. </p>
<p>To understand how giraffes are faring across Africa, <a href="https://scholar.google.com/citations?user=f3D2QOcAAAAJ&hl=en">conservation ecologists like me</a> are studying how they interact with their habitats across vast geographic scales. We use space-age technology and advanced statistical approaches that our ancient ancestors could have scarcely imagined to understand how giraffes can better coexist with people. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Image of a giraffe carved in red rock." src="https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/542627/original/file-20230814-22-vdxtbu.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">Giraffes are featured prominently in ancient petroglyphs across Africa, such as this one in Twyfelfontein, Namibia, which dates back thousands of years.</span>
<span class="attribution"><span class="source">Michael Brown</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Many habitats and challenges</h2>
<p>Giraffes may all look similar to the casual viewer, but in fact there are <a href="https://doi.org/10.1016/j.cub.2021.04.033">four distinct species</a>. By our best estimates, there are <a href="https://doi.org/10.1016/B978-0-12-821139-7.00139-2">roughly 117,000 giraffes remaining in the wild</a>, living in <a href="https://doi.org/10.1111/mam.12165">21 African countries</a>. </p>
<p>Across this huge expanse, giraffes make their homes in many different environments with varied levels of human influence. For example, in the relatively arid Sahel region of Niger, they live among communal farmers entirely outside of formally protected areas. In contrast, along the Nile in Uganda’s national parks, they browse through lush savannas that are formally protected by dedicated rangers. </p>
<p>Each of these areas has unique bioclimatic conditions and conservation philosophies. There is <a href="https://giraffeconservation.org/programmes/conservation-strategies/">no one-size-fits-all approach</a> for protecting giraffe habitats and <a href="https://doi.org/10.1080/10871209.2021.1885768">promoting coexistence with people</a>. </p>
<p>Researchers are taking advantage of these diverse conditions to learn how giraffes move throughout this range. <a href="https://doi.org/10.1098/rspb.2023.0912">In a recently published paper</a>, I worked with colleagues from academia and conservation organizations to conduct the largest ever tracking study to better understand how and why giraffes move at large scales. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four images of giraffes in diverse African settings." src="https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/542628/original/file-20230814-24-pw6hay.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&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 four species of giraffes inhabit remarkably different habitats across Africa, from lush savannas to desert.</span>
<span class="attribution"><span class="source">Michael Brown</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Tracking wide-ranging animals</h2>
<p>Over the past decade, our collaborative conservation research team, spearheaded by the <a href="https://giraffeconservation.org/">Giraffe Conservation Foundation</a>, has embarked on an ambitious pan-African giraffe-tracking study to better understand giraffes’ movements across these diverse landscapes. </p>
<p>Each tracking operation contributes to local studies by telling us something interesting about giraffe behavior. For example, we published the first description of <a href="https://doi.org/10.3389/fevo.2019.00524">partial migration in a Ugandan giraffe population</a>, showing that giraffes can have complicated seasonal movements. </p>
<p>These studies also are important for guiding local management of giraffes. Partnering with organizations like <a href="https://www.earthranger.com/">EarthRanger</a>, which develops software to support conservation initiatives, we have pioneered the use of animal movement data to inform active conservation management. </p>
<p>We share giraffe location data in real time with rangers in protected areas to guide day-to-day conservation actions. As an example, we run continuous analytics on the giraffe data that alert teams on the ground when a giraffe stops moving or leaves the boundaries of a national park. With this information, teams can follow up quickly and address risks, such as when giraffes might be straying into dangerous areas.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Bry-gJU-cis?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In October 2021, conservation scientists and local wildlife officials translocated 10 South African giraffes over 1,600 miles (2,600 kilometers) from South Africa to Malawi. There they joined 13 giraffes already in Majete Wildlife Reserve, helping to expand the group into a sustainable population.</span></figcaption>
</figure>
<p>To look at these patterns at a larger scale in our recent study, we analyzed GPS tracking data from 148 giraffes, representing all four species from across 10 countries. We wanted to understand how giraffes may change their movements in response to human pressures and the availability of vegetation.</p>
<p>We used environmental data from satellite imagery, linking the giraffes’ locations to the exact conditions that the animals were moving through. Since the work drew from information collected across Africa through different GPS devices, we developed statistical techniques to harmonize the datasets and make the results directly comparable across ecosystems. </p>
<p>Overall, we found that giraffes cover impressively large areas. On average, each animal has a home range of about 140 square miles (360 square kilometers) – <a href="https://www.census.gov/quickfacts/fact/table/philadelphiacitypennsylvania/PST045222">nearly equivalent to the surface area of Philadelphia</a> – and travels about 8.5 miles (14 kilometers) every day. One of the biggest movers in our study, a female northern giraffe in Niger that navigated among communities raising livestock in the dry Sahel, covered a home range of nearly 1,500 square miles (3,860 square kilometers) – larger than the <a href="https://www.ri.gov/facts/history.php">land area of Rhode Island</a>. </p>
<p>Giraffes’ movements changed significantly based on the availability of woody vegetation and the level of human presence. Those in areas with plenty of woody vegetation didn’t cover as much ground as their counterparts in more barren zones, since the former had most of the resources they needed close by. Giraffes also tended to move less in places with significant human development – probably because of man-made barriers to their movements, like settlements, fences and roads.</p>
<p>In mixed areas with some development and some open spaces, we observed that giraffes covered more ground as they navigated these patchy environments. They traveled faster and covered larger areas when they were moving between resource-rich zones and more heavily developed areas.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two giraffes at the edge of a road watch a car pass." src="https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540456/original/file-20230801-21-xj7o8h.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">Across their range, giraffes are navigating increasingly developed landscapes.</span>
<span class="attribution"><span class="source">Michael Brown, GCF</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Giraffe movements inform conservation</h2>
<p>Understanding how giraffes respond to changes in environmental conditions is critical for their conservation. Climate change is making the availability of vegetation less predictable, and human populations in these areas are continuing to grow. Conservation strategies will need to account for giraffes’ changing movements as the animals respond to these shifts. </p>
<p>It also is important to develop principles for giraffe movement so that we can better predict how they might move in new environments. Conservation groups and governments are increasingly using <a href="https://giraffeconservation.org/programmes/conservation-translocations/">conservation translocations</a> – capturing wild giraffes and moving them to new habitats – as a tool to reestablish populations in areas where giraffes had previously become extinct. </p>
<p>Our movement data from giraffes across Africa is casting new light on their responses to different conditions and providing important information for conserving these iconic animals in a rapidly changing world.</p><img src="https://counter.theconversation.com/content/210263/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Brown works for the Giraffe Conservation Foundation and is an affiliated researcher for the Smithsonian National Zoo and Conservation Biology Institute. He receives funding from the Giraffe Conservation Foundation and its many supporters and is affiliated with the Smithsonian National Zoo and Conservation Biology Institute.</span></em></p>The largest ever giraffe tracking study shows how these massive animals are responding to human pressures across many different habitats throughout Africa.Michael Brown, Conservation Science Fellow, Smithsonian InstitutionLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2099552023-08-14T18:42:58Z2023-08-14T18:42:58ZThis solar cycle, the sun’s activity is more powerful and surprising than predicted<figure><img src="https://images.theconversation.com/files/541795/original/file-20230808-15-85ytq4.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1920%2C1080&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A coronal mass ejection on the solar surface.</span> <span class="attribution"><span class="source">(NASA/GSFC/SDO)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/this-solar-cycle-the-suns-activity-is-more-powerful-and-surprising-than-predicted" width="100%" height="400"></iframe>
<p>What do you feel when you see the aurora? </p>
<p>Otherwise known as the northern or southern lights, an aurora is light emitted by upper atmospheric particles as they interact with energized ones <a href="https://superdarn.ca/tutorials-11">from the magnetosphere</a>.</p>
<p>It’s an awe-inspiring and otherworldly event that those living at high latitudes can experience often. In <a href="https://creeliteracy.org/2018/05/01/northern-lights-creesimonsays/">Cree and Ojibwe teachings</a>, the northern lights are ancestral spirits who remain and communicate from the sky. </p>
<p>To scientists, the aurora is an infinitely complex amalgamation of <a href="https://www.nasa.gov/ionosphere">ionospheric</a> dynamics, a manifestation of Earth’s intrinsic connection to the sun. To industry, it’s a risk factor.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&rect=0%2C2%2C936%2C524&q=45&auto=format&w=1000&fit=clip"><img alt="green lights ribbon in the sky above powerlines" src="https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&rect=0%2C2%2C936%2C524&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540229/original/file-20230731-17-9pbazi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=425&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The aurora borealis seen above the Saskatoon SuperDARN space weather radar.</span>
<span class="attribution"><span class="source">(A. Reimer)</span></span>
</figcaption>
</figure>
<h2>The Starlink destruction event</h2>
<p>In February 2022, <a href="https://www.bbc.com/news/world-60317806">SpaceX launched 49 Starlink internet satellites into a low-Earth orbit (LEO)</a>. This was the 36th Starlink launch that SpaceX had carried out, and one that they anticipated to go off without a hitch, just like the 35 before. </p>
<p>On launch day, a <a href="https://www.swpc.noaa.gov/phenomena/coronal-mass-ejections">coronal mass ejection</a> — a large burst of plasma expelled from the sun — struck Earth. It caused a geomagnetic storm in the atmosphere between around 100 and 500 kilometres in altitude, the target range for Starlink. </p>
<p>This event injected an immense amount of electromagnetic energy straight into Earth’s upper atmosphere. It produced <a href="https://www.youtube.com/watch?v=q_GYySXTtio">beautiful auroral displays</a>, but the energy also increased the density of the air. A higher air density typically isn’t a big deal for LEO satellites, because it’s already extremely low at usual operational altitudes (upwards of 400 kilometres). </p>
<p>Starlink, however, was initially <a href="https://doi.org/10.1029/2022SW003074">launched into an altitude of 210 kilometres</a>. That’s much closer to Earth, with an exponentially higher air density. Thirty-eight out of those 49 initial launch satellites were subsequently lost due to atmospheric drag from the dense atmosphere, <a href="https://doi.org/10.1051/swsc/2022034">pulling them back to Earth</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/mUlAz_Oxv4Q?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Starlink satellites burning up in the atmosphere over Puerto Rico, Feb. 7, 2022.</span></figcaption>
</figure>
<h2>Surprising solar cycle</h2>
<p>The sun undergoes a cycle — an 11-year one, to be exact — from which its activity increases and decreases periodically. At the peak of a cycle, we see more sunspots on the solar surface, more radiation emitted, and more solar flares. Geomagnetic storms like the one that caused the Starlink destruction event are a relatively common occurrence, especially when the sun reaches the peak of its 11-year cycle of strengthening and weakening activity. </p>
<p>In the previous cycle, which ended in 2019 (the 24th tracked cycle since 1755), <a href="https://doi.org/10.1016/j.asr.2022.10.033">there were 927 storms classed as moderate or weak alone</a> — an average of one every five or so days. </p>
<p>We’re currently four years into solar cycle 25, but this one has already proven surprising. The maximum activity of the 25th cycle was predicted to occur in 2025, but solar activity has already exceeded that. This means we’ve been seeing more geomagnetic storms, more auroral displays (and at lower latitudes than usual) and, potentially, more hazardous conditions for LEO satellites.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A plotted graph showing solar cycle sunspots" src="https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=221&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=221&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=221&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=278&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=278&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540308/original/file-20230731-23-cwg668.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=278&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Solar activity as the number of sunspots visible on the solar surface. The number of sunspots seen is already considerably higher than what is expected from the solar maximum, two years ahead of schedule.</span>
<span class="attribution"><a class="source" href="https://www.swpc.noaa.gov/products/solar-cycle-progression">(National Oceanic and Atmospheric Administration)</a></span>
</figcaption>
</figure>
<h2>Space weather — the unseen force of nature</h2>
<p>If geomagnetic storms are so common, why don’t they cause more issues? <a href="https://www.maine.gov/mema/maine-prepares/preparedness-library/geomagnetic-storms">The reality is that they do</a>, but the consequences are much less obvious than satellites burning up in the atmosphere.</p>
<p>When space weather energy enters Earth’s upper atmosphere, for example, the ionospheric composition changes in addition to the air getting denser. High-frequency, or “shortwave,” radio communication depends on a predictable ionosphere to broadcast long distances. </p>
<p>Geomagnetic storms that affect ionospheric composition can cause <a href="https://doi.org/10.1029/2018SW002008">radio blackouts</a>, such as a <a href="https://www.space.com/x-class-solar-flare-radio-blackout-august-2023">disruption in North America on Aug. 7</a>. Even minor storms can cause the degradation of radio signals used in military and maritime systems, aviation communication or ham radio. </p>
<p>Extreme storms can cause radio blackouts lasting hours, and for an entire side of the globe. Storms that big can also cause more discernible problems, such as the nine-hour <a href="http://www.hydroquebec.com/learning/notions-de-base/tempete-mars-1989.html">electricity outage experienced by Hydro-Québec in 1989</a>.</p>
<h2>Space weather warning systems</h2>
<p>It’s not all doom and disintegrating rockets, however. We can detect when a solar flare leaves the surface of the sun and predict roughly when it will affect the Earth, giving forewarning to certain types of storms and <a href="https://www.aurorawatch.ca/">chances to see the aurora</a>.</p>
<p>For many storms however, there is very little or no predictive capability because it depends on how the Earth’s magnetic field interacts with the solar wind, which is harder to see. </p>
<p>Nowcasting — using real-time data to understand conditions as they occur — is one of our best tools. With instruments such as ground-based radar and magnetometers on satellites, <a href="https://doi.org/10.1029/2023GL103733">we can estimate the electromagnetic space weather energy entering the atmosphere almost instantaneously</a>. </p>
<p>As for why SpaceX lost satellites in February 2022 during a minor geomagnetic storm, that was just a matter of timing. The loss of the satellites, however, is a stunning reminder of the power of the universe we live in.</p><img src="https://counter.theconversation.com/content/209955/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Daniel Billett receives funding from the European Space Agency and the Natural Sciences and Engineering Research Council of Canada. </span></em></p>We’re currently a few years into the 25th studied solar cycle. An 11-year period of sun activity, this solar cycle is more active than previously expected.Daniel Billett, Postdoctoral Fellow in Space Physics, University of SaskatchewanLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2093002023-07-18T12:27:31Z2023-07-18T12:27:31ZReturning to the Moon can benefit commercial, military and political sectors – a space policy expert explains<figure><img src="https://images.theconversation.com/files/536343/original/file-20230707-15-g8cdkp.jpeg?ixlib=rb-1.1.0&rect=0%2C8%2C1421%2C1012&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Moon marks new territory for commercial, military and geopolitical interests. </span> <span class="attribution"><a class="source" href="https://www.jpl.nasa.gov/images/pia02322-triptych-of-the-moon">NASA/JPL/Cassini Imaging Team/University of Arizona</a></span></figcaption></figure><p>NASA’s <a href="https://www.nasa.gov/specials/artemis/">Artemis program</a> aims to return humans to the Moon for the first time in more than 50 years, with the first human landing <a href="https://www.nasa.gov/feature/artemis-iii">currently scheduled for 2025</a>. This goal is not just technically ambitious, but it’s also politically challenging. The Artemis program marks the first time since the Apollo program that an effort to send humans to the Moon has been <a href="https://www.washingtonpost.com/technology/2021/03/02/biden-space-artemis-moon-trump/">supported by two successive U.S. presidents</a>. </p>
<p>As a <a href="https://scholar.google.com/citations?user=aESo-coAAAAJ&hl=en">scholar of international affairs who studies space</a>, I’m interested in understanding what allowed the Artemis program to survive this political transition where others failed. <a href="https://doi.org/10.1016/j.spacepol.2023.101548">My research suggests</a> that this program is not just <a href="https://theconversation.com/building-telescopes-on-the-moon-could-transform-astronomy-and-its-becoming-an-achievable-goal-203308">about advancing science</a> and technology or <a href="https://theconversation.com/meet-the-next-four-people-headed-to-the-moon-how-the-diverse-crew-of-artemis-ii-shows-nasas-plan-for-the-future-of-space-exploration-203214">inspiring the public</a>. It also offers practical benefits for the commercial sector and the military and an opportunity to reinforce U.S. global leadership. </p>
<h2>Commercial interest in the Moon</h2>
<p>Several companies around the world, including both startups and established aerospace firms, have begun working on missions to the Moon. Some, like Japan-based <a href="https://ispace-inc.com/">iSpace</a> and U.S.-based <a href="https://www.astrobotic.com/">Astrobotic</a>, are developing commercial lunar landers and have plans to eventually collect lunar resources, such as <a href="https://theconversation.com/back-to-the-moon-a-space-lawyer-and-planetary-scientist-on-what-it-will-take-to-share-the-benefits-of-new-lunar-exploration-podcast-202415">water</a> or <a href="https://www.nasa.gov/press-release/nasa-selects-companies-to-collect-lunar-resources-for-artemis-demonstrations">minerals</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ocDzndmmE8I?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">NASA is planning to return to the Moon with Artemis missions. This video describes where on the Moon they may land, and how they’ll decide.</span></figcaption>
</figure>
<p>For now, efforts to return to the Moon are largely funded by government space agencies, like NASA or the <a href="https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Exploration/Astrobotic_team_to_study_delivery_of_lunar_resources_mission">European Space Agency</a>. However, many experts talk about the growth of a “<a href="https://doi.org/10.1016/j.actaastro.2017.10.005">cislunar economy</a>,” where companies make money through their activities in and around the Moon.</p>
<p><a href="https://www.ida.org/research-and-publications/publications/all/d/de/demand-drivers-of-the-lunar-and-cislunar-economy">Expert studies</a> suggest that it will be decades before many activities – like mining lunar resources or collecting solar energy on the Moon – will generate profits. But in the meantime, government space programs can leverage commercial innovation to cut costs, spur innovation and accelerate their programs. And some commercial activity, such as lunar tourism, <a href="https://www.ida.org/research-and-publications/publications/all/d/de/demand-drivers-of-the-lunar-and-cislunar-economy">may be profitable in the near future</a>. SpaceX has already sold one <a href="https://dearmoon.earth/">trip to the Moon</a>, tentatively scheduled for launch in 2024. </p>
<p>Companies entering the market early may have an advantage. Crowding is unlikely to be an issue in the near term – the Moon has a <a href="https://theconversation.com/how-big-is-the-moon-let-me-compare-118840">surface area</a> roughly equivalent to the entire Asian continent. Even at the poles, <a href="https://www.nasa.gov/press-release/nasa-identifies-candidate-regions-for-landing-next-americans-on-moon">multiple sites</a> offer access to both water ice and solar illumination. </p>
<p>However, the first companies on the Moon may set precedents for the extent of lunar mining allowed, as well as the safety and sustainability protocols that others coming later may follow. The United Nations has established a <a href="https://www.unoosa.org/oosa/en/ourwork/copuos/lsc/space-resources/index.html">working group</a> to examine the legal issues related to using space resources, but it won’t finish its first set of proposed principles until 2027. In the meantime, commercial entities are <a href="https://doi.org/10.1038/d41586-023-01441-y">already attempting</a> to land on the Moon.</p>
<h2>Military interest in the Moon</h2>
<p>In 2020, the head of <a href="https://theconversation.com/space-force-sounds-like-a-joke-thanks-to-pop-culture-that-could-be-a-problem-for-an-important-military-branch-155265">the U.S. Space Force</a> referred to the Moon as “<a href="https://www.airandspaceforces.com/raymond-foresees-cislunar-space-as-key-terrain-guardians-going-to-space/">key terrain</a>,” and the Air Force Research Laboratory is funding an experimental satellite called <a href="https://breakingdefense.com/2022/11/oracles-vision-understanding-cislunar-satellite-images-poses-afrls-biggest-challenge/">Oracle</a>, scheduled for launch in 2026. Oracle will monitor the space between the Earth and the Moon. </p>
<p>The U.S. military has decades of experience in <a href="https://doi.org/10.1016/j.spacepol.2021.101444">monitoring spacecraft orbiting the Earth</a>. It could use this expertise to <a href="https://breakingdefense.com/2022/11/critically-important-new-white-house-strategy-for-cislunar-research-echoes-space-force/">support safety and security</a> as commercial and civil governmental activity near the Moon increases. They could also provide the United States with better intelligence on the space activities of strategic competitors, like <a href="https://www.nbcnews.com/mach/news/chinese-spacecraft-makes-first-landing-moon-s-far-side-ncna954066">China</a>.</p>
<p>Some individuals in the space sector <a href="https://spaceforcejournal.org/3859-2/">go further</a> and suggest that the military should watch for weapons hidden in deep space or on the far side of the moon. However, the physics and economics of space suggest that these uses are costly, with <a href="https://www.uscc.gov/annual-report/2019-annual-report-congress">little practical benefit</a>.</p>
<p>While leveraging U.S. military expertise in space makes sense, there are reasons not to take developments in this area too far. Military advances like these – even if done in support of civil and commercial goals – may <a href="https://www.politico.com/news/2022/03/12/space-force-moon-pentagon-00016818">raise suspicion</a> from other nations, potentially leading to increased military space activity on their part, and ultimately increasing tensions.</p>
<h2>Geopolitical concerns</h2>
<p>The Apollo program is famous for its role in the U.S. and the Soviet Union’s mid-20th century “space race.” The United States’ ability to land humans on the Moon was interpreted by many around the world as evidence of U.S. technological superiority and the <a href="https://millercenter.org/the-presidency/educational-resources/space-race">capabilities of a democratic and capitalist society</a>. Some have suggested that the United States is now in a <a href="https://foreignpolicy.com/2019/08/22/america-is-losing-the-second-space-race-to-china/">new space race</a>, this time with China. China <a href="https://www.washingtonpost.com/world/2023/05/29/china-moon-space-astronauts-lunar/">recently accelerated</a> its plans to send humans to the Moon. </p>
<p>While <a href="https://theconversation.com/is-the-us-in-a-space-race-against-china-203473">not everyone agrees</a> that such a race is taking place, the use of this terminology by U.S. political leaders, including <a href="https://www.space.com/nasa-bill-nelson-china-space-race-moon">current NASA Administrator</a> Bill Nelson, and its ubiquity in <a href="https://www.theguardian.com/science/2021/jul/16/the-space-race-is-back-on-but-who-will-win">global</a> <a href="https://www.scmp.com/news/china/military/article/3162196/china-us-space-race-heats-chinese-firm-plans-over-40-launches">media</a> <a href="https://japantoday.com/category/world/a-new-space-race-china-adds-urgency-to-us-return-to-moon">coverage</a> suggest that many will view efforts to land humans on the Moon in this way. If China lands humans on the Moon before the United States, people around the world may see this as evidence of <a href="https://thehill.com/opinion/technology/440751-returning-to-the-moon-to-gain-soft-political-power/">China’s role as a global leader</a> and the capabilities of its communist government. </p>
<p>The return to the Moon is not just about competition. It also offers nations opportunities to engage in international cooperation. <a href="https://csis-website-prod.s3.amazonaws.com/s3fs-public/publication/220215_Johnson_FlyMe_Moon.pdf?VersionId=eBOSyAKB1ite5cort60IluuBQWvYyADa">More than 20 nations</a> have announced plans to undertake missions to the Moon. Just as the United States is leveraging commercial developments, the U.S. is working with international partners, as well. Europe, Japan and Canada have already joined the United States as partners on the <a href="https://www.nasa.gov/gateway">Lunar Gateway</a>, a space station that will orbit the Moon, with the first modules expected to launch in 2025.</p>
<p>The United States is also seeking international support for the <a href="https://www.nasa.gov/specials/artemis-accords/index.html">Artemis Accords</a>, a set of principles for responsible lunar exploration and development. As of July 2023, 27 nations had signed the accords. This includes not just close allies like the United Kingdom, Canada and Japan, but also less traditional partners, such as Rwanda, Nigeria and the United Arab Emirates. <a href="https://breakingdefense.com/2023/06/india-signs-artemis-accords-tightening-ties-with-us-in-space-race-with-china-sources/">India’s signing</a> of the accords in June 2023 was seen as a sign of strengthening ties between the U.S. and India.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A suited man stands at a NASA podium, with three panelists seated at a table next to him. In the background a green reads " src="https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=422&fit=crop&dpr=1 600w, https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=422&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=422&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=530&fit=crop&dpr=1 754w, https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=530&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/537534/original/file-20230714-27-mvzy1s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=530&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Twenty-seven countries have signed on to the Artemis Accords, an international collaboration with the goal of encouraging responsible behavior on and around the Moon.</span>
<span class="attribution"><a class="source" href="https://media.gettyimages.com/id/1252567156/photo/in-this-handout-image-provided-by-nasa-nasa-administrator-bill-nelson-delivers-remarks-prior.jpg?s=612x612&w=0&k=20&c=xCp9Lb7jh7zWaj0oMRw9W08h9BjtLyQFl1SWXgceVRs=">Joel Kowsky/NASA via Getty Images</a></span>
</figcaption>
</figure>
<p>It’s worth noting that China’s lunar program also emphasizes international engagement. In 2021, <a href="https://www.space.com/china-russia-moon-base-ilrs">China announced plans</a> to develop the International Lunar Research Station in partnership with Russia, and it has <a href="https://www.voanews.com/a/in-china-us-space-race-beijing-uses-space-diplomacy/6284826.html">invited other nations to join</a>, as well. Sweden, France, Italy, Pakistan and the United Arab Emirates are all participating in China’s upcoming <a href="https://spacenews.com/china-seeks-new-partners-for-lunar-and-deep-space-exploration/">lunar lander mission</a>. </p>
<p>Ever since humans last left the Moon in 1972, many have dreamed about the days when people would return. But for decades, these efforts have hit political roadblocks. This time, the United States’ plans to return to the Moon are likely to succeed – it has the cross-sector support and the strategic importance to ensure continuity, even during politically challenging times.</p><img src="https://counter.theconversation.com/content/209300/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mariel Borowitz receives funding from the the National Aeronautics and Space Administration, the U.S. Department of Defense, and the U.S. National Science Foundation. </span></em></p>While a return to the Moon will allow the U.S. to collaborate with other nations interested in space, this endeavor is also complicated by geopolitical tensions.Mariel Borowitz, Associate Professor of International Affairs, Georgia Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2061152023-07-12T14:37:12Z2023-07-12T14:37:12ZCôte d’Ivoire is launching its first satellite for Earth observation – and it’s locally made<figure><img src="https://images.theconversation.com/files/533450/original/file-20230622-19-z1rzbl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Illustration of a view of Africa from space. </span> <span class="attribution"><span class="source">Getty Images</span></span></figcaption></figure><p><em>Côte d’Ivoire has <a href="https://www.ecofinagency.com/telecom/0205-44484-cote-d-ivoire-to-launch-its-first-satellite-in-space-by-august-2024">announced plans</a> to launch its first satellite within the next two years. A team of scientists in the fields of astrophysics and geology tell The Conversation Africa about the potential benefits of this development and how the country plans to realise its space industry ambitions.</em> </p>
<h2>What kind of satellite does Côte d'Ivoire plan to launch?</h2>
<p>YAM-SAT-CI 01 will be a nanosatellite for the observation of the Earth. A nanosatellite is a small satellite, weighing from 1kg to 10kg. It will be equipped with a camera which can provide images of the coast, forests, natural parks and urban areas of the country. </p>
<p>The construction of the satellite is 100% Ivorian. It has been entrusted to <a href="https://www.facebook.com/UNIVERSALKONSTRUCTORSASSOCIATED/?locale=ms_MY">Universal Konstructors Associated</a>, a private Ivorian company promoting scientific and technological development in Côte d'Ivoire, in partnership with the <a href="https://inphb.ci/">Institut National Polytechnique Félix Houphouët-Boigny</a> of Yamoussoukro.</p>
<p>It’s the first step towards more sophisticated satellites and sensors which have many <a href="https://theconversation.com/nanosatellite-launch-is-a-big-step-forward-for-african-space-science-175069">applications</a>. For example they can detect, monitor and map threats to national security, illegal migration, <a href="https://theconversation.com/technique-developed-in-kenya-offers-a-refined-way-to-map-tree-cover-76709">deforestation</a>, illegal gold mining activities, <a href="https://theconversation.com/dust-in-the-atmosphere-is-a-sign-of-trouble-in-south-africas-maize-fields-147939">soil humidity</a> and water reservoirs. They can help minimise the consequences of floods or droughts. </p>
<p>In Côte d’Ivoire, such a satellite could assist the government’s efforts to regulate artisanal mining and combat illegal activities and destruction of the <a href="https://theconversation.com/eyes-in-the-sky-and-on-the-ground-are-helping-forest-conservation-in-cameroon-73695">environment</a>. </p>
<p>These applications rely on sophisticated image processing algorithms, including the use of artificial intelligence.</p>
<h2>What are the other potential benefits and spinoffs?</h2>
<p>Earth observation provides data for agriculture, disaster management and urban planning. The satellite supports various applications, including monitoring vegetation health, mapping water resources, and analysing urban growth patterns.</p>
<p>Aside from the technology’s direct benefits, it serves the scientific and economic development of the nation.</p>
<p>The project of building and launching a satellite is generally accompanied by capacity building in many sectors related to the space industry. It involves engineers and scientists to develop sensors and the ground segment to track and communicate with the satellite. </p>
<p>Other important benefits of such projects include a wider use of space-science technology. A satellite launch may lead to greater use of Earth observations data and products, provided by numerous satellites orbiting around our planet. </p>
<h2>Who will be involved in this project?</h2>
<p>The academic and private sectors all have a role to play in this scientific, technical and political adventure. </p>
<p>The Institut National Polytechnique Félix Houphouet-Boigny has already planned to set up new curricula in the domain of space and aeronautics. This will directly benefit a new generation of young engineers. And an <a href="https://lastronomieafrique.com/author/davidbaratoux/">Ivoirian Association for Astronomy</a> has been launched. Its outreach activities to promote astronomy and space science to the wider public will increase the scientific literacy of the population. It may inspire the younger generation towards scientific careers. </p>
<p>Lastly, the University Félix Houphouët-Boigny has a laboratory specialising in the observation of the Earth from space: the <a href="https://www.curat-edu.org/">Centre Universitaire de Recherche et d'Application en Télédétection</a>. Its students may also contribute to the design, mission strategy and applications of Côte d’Ivoire’s satellites.</p>
<h2>What are other African countries doing in space technology?</h2>
<p>The <a href="https://spaceinafrica.com/reports/">2022 space industry report</a> of the consulting company Space in Africa says the value of the industry in Africa is expected to reach US$22.64 billion in 2026. That’s up from US$19.49 billion in 2021. The report indicates that African nations allocated US$534.9 million to space programmes in 2022 compared to US$523.2 million in 2021. These investments indicate that African countries are preparing for wider use of space technology in handling <a href="https://theconversation.com/starlink-spacexs-new-internet-service-could-be-a-gamechanger-in-africa-200746">challenges</a> affecting the continent.</p>
<p>For instance, on 23 April 2023 <a href="https://ksa.go.ke/taifa-1-satellite/">Kenya launched its first satellite</a>, called Taifa-1, with the help of SpaceX. The satellite is equipped with an optical camera and is expected to provide agricultural and environmental monitoring data for Kenya. </p>
<p>In 2021, Tunisia <a href="https://www.lepoint.fr/afrique/la-tunisie-lance-son-premier-satellite-23-03-2021-2418938_3826.php#11">launched</a> its first 100% Tunisian-made satellite. <a href="https://www.un-spider.org/news-and-events/news/zimbabwe-and-uganda-launched-their-first-satellites-zimsat-1-and">Zimbabwe, Uganda</a>, <a href="https://www.pixalytics.com/egyptsat-a-launched/">Egypt</a> and Angola have also launched satellites in the last 12 months. In April 2023, President Macky Sall announced <a href="https://africanews.space/president-macky-sall-announces-the-launch-of-the-senegalese-space-study-agency/">the launch of the Senegalese Agency of Space Studies</a>. </p>
<p>Egypt, <a href="https://theconversation.com/theres-a-case-for-nigeria-and-south-africa-to-cooperate-on-outer-space-activities-174635">Nigeria</a> and South Africa are the most advanced African countries on space issues. For instance, ZACube, launched in December 2018, is a <a href="https://theconversation.com/cool-cubes-are-changing-the-way-we-play-in-space-41621">nanosatellite</a> developed by the South African National Space Agency and local universities. It focuses on the safety of maritime traffic in South African coastal waters.</p>
<p>Nigeria’s National Space Research and Development Agency was established in 1999. It has launched five satellites since 2003. In December 2022, Nigeria and Rwanda became the first African countries to sign the <a href="https://theconversation.com/outer-space-rwanda-and-nigeria-sign-an-accord-for-more-responsible-exploration-why-this-matters-203202">Artemis Accords</a>, a NASA-led framework outlining best practices for sustainable space exploration. </p>
<p>It’s clear that more and more African countries are investing in space technologies. </p>
<p>The first step is to educate the population about space and the benefits of investing in space technologies. We need to create space-related training courses and promote space science in African countries.</p><img src="https://counter.theconversation.com/content/206115/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Baratoux receives funding from French National Research Institute for Sustainable Development and from the Centre National de la Recherche Scientifique (France)</span></em></p><p class="fine-print"><em><span>Aziz Diaby Kassamba is affiliated with Université Félix Houphouët-Boigny and Association Ivoirienne d'Astronomie. </span></em></p><p class="fine-print"><em><span>Marc Harris Yao Fortune, Marie Korsaga, and Pancrace Aka 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>Côte d’Ivoire’s nanosatellite is the first step towards applications that monitor environmental harm and illegal activities and assist in planning for development.David Baratoux, Geologist, Institut de recherche pour le développement (IRD)Aziz Diaby Kassamba, Enseignant chercheur en physique de l'espace, Université Félix Houphouët-Boigny. Cocody, Côte-d'IvoireMarc Harris Yao Fortune, Enseignant-chercheur, astrophysicien , Université Félix Houphouët-Boigny. Cocody, Côte-d'IvoireMarie Korsaga, Enseignant-Chercheur en physique chimie, Université Joseph Ki-ZerboPancrace Aka, Épistémologue, Historien des sciences et Logicien, Université Félix Houphouët-Boigny. Cocody, Côte-d'IvoireLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2083232023-06-22T16:32:36Z2023-06-22T16:32:36ZUkraine recap: counteroffensive makes slow progress while diplomacy fails to make any ground at all<p>So the Ukrainian counteroffensive is well and truly underway, even if progress is measured in metres rather than the rapid advances that characterised Ukraine’s highly successful push last autumn. Volodymyr Zelensky himself has confirmed this, saying progress has been “slower than desired” and noting that the Russian invaders have mined an estimated 200,000 sq km of frontline territory.</p>
<p>But then, as he has also noted, this war is not a “Hollywood movie” that will neatly resolve the way many might wish. And the analysts at think tank the <a href="https://www.understandingwar.org/backgrounder/russian-offensive-campaign-assessment-june-21-2023">Institute for the Study of War (ISW)</a> believe we are more likely to see a series of testing exercises, designed to highlight Russian weak points in preparation for a bigger push later in the campaigning season.</p>
<p>One expert pondering the timing of the counteroffensive is Cyrille Bret, an expert in defence studies at Sciences Po, who asks: <a href="https://theconversation.com/ukraines-long-awaited-counteroffensive-has-finally-begun-but-why-now-and-to-what-end-207689">why now and to what end?</a></p>
<p>On the one hand, waiting a month or so would undoubtedly give Ukraine the advantage of more advanced western military hardware. But there are other factors – strategic and political – that would have driven Zelensky to give the order to begin. Not least of these is that he faces a general election in Ukraine in the autumn and needs to have something to show voters. </p>
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<img alt="" src="https://images.theconversation.com/files/510322/original/file-20230215-22-dna0kj.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/510322/original/file-20230215-22-dna0kj.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510322/original/file-20230215-22-dna0kj.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510322/original/file-20230215-22-dna0kj.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510322/original/file-20230215-22-dna0kj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510322/original/file-20230215-22-dna0kj.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510322/original/file-20230215-22-dna0kj.png?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">
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<p><em>Since Vladimir Putin sent his war machine into Ukraine on February 24 2022, The Conversation has called upon some of the leading experts in international security, geopolitics and military tactics to help our readers <a href="https://theconversation.com/uk/topics/ukraine-12-months-at-war-134215?utm_source=TCUK&utm_medium=linkback&utm_campaign=Ukraine12Months">understand the big issues</a>. You can also <a href="https://theconversation.com/uk/newsletters/ukraine-recap-114?utm_source=TCUK&utm_medium=linkback&utm_campaign=Ukraine12Months">subscribe to our fortnightly recap</a> of expert analysis of the conflict in Ukraine.</em></p>
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<p>And round about then is when the interminable US 2024 presidential election machinery starts to grind in earnest. A growing number of Americans becoming increasingly ambivalent about the huge sums their government is ploughing into the war. So some good news from Kyiv could be just what Biden needs to bolster his chances against Republican candidates who are openly questioning their country’s involvement. A great deal hangs on the next weeks and months.</p>
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<strong>
Read more:
<a href="https://theconversation.com/ukraines-long-awaited-counteroffensive-has-finally-begun-but-why-now-and-to-what-end-207689">Ukraine's long-awaited counteroffensive has finally begun - but why now and to what end?</a>
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<p>There’s been a fair bit of politics going on inside Russia, too. It’s long been no secret that the country’s defence minister, Sergei Shoigu, and the boss of the Wagner Group private military company, Yevgeny Prigozhin loathe each other. Not being held back by the constraints of public office, Prigozhin has been liberal with his criticisms of Shoigu and Russia’s military commander, Valery Gerasimov, calling them “stupid” and responsible for “criminal orders”.</p>
<p>Shoigu, a politician to his bootstraps, has opted for a rather subtler play – talking Putin into passing a law which will bring all Russia’s non-state militias under the control of the ministry of defence. It could be awkward, to say the least, <a href="https://theconversation.com/ukraine-war-ukraine-war-kremlin-attempt-to-control-private-militaries-like-wagner-group-fails-to-address-rivalry-between-factions-208213">writes Tracey German</a>, a professor of conflict and security at King’s College London.</p>
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Read more:
<a href="https://theconversation.com/ukraine-war-aborted-wagner-group-rebellion-shows-how-putins-attempt-to-unify-russian-forces-has-failed-to-quell-factional-rivalries-208213">Ukraine war: aborted Wagner Group rebellion shows how Putin's attempt to unify Russian forces has failed to quell factional rivalries</a>
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<h2>From the sky to the seabed</h2>
<p>One of the reasons we know so much about what is happening on the battlefield is that, to an unprecedented degree, progress is being watched and relayed by satellites which can plot the action to just about the nearest metre.</p>
<p>Christopher Morris, who teaches military strategy at the University of Portsmouth, believes access to superior commercial satellite tech has given Ukraine <a href="https://theconversation.com/ukraine-war-offensive-use-of-satellite-tech-a-sign-of-how-conflict-is-increasingly-moving-into-space-207641">a significant edge</a> in targeting Russian armour. Hi-res images of Russian defensive installations will allow Ukraine’s planners to work out ways to target, destroy or circumvent them.</p>
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<strong>
Read more:
<a href="https://theconversation.com/ukraine-war-offensive-use-of-satellite-tech-a-sign-of-how-conflict-is-increasingly-moving-into-space-207641">Ukraine war: offensive use of satellite tech a sign of how conflict is increasingly moving into space</a>
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<a href="https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map showing areas of Ukraine under Russian control in red." src="https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=847&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=847&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=847&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1064&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1064&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533544/original/file-20230622-24-iswfjt.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1064&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 progress of the conflict in Ukraine as of June 21.</span>
<span class="attribution"><span class="source">Institute for the Study of War</span></span>
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<p>Meanwhile at the bottom of the oceans there are more than 1.4 million kilometres of vitally important infrastructure – data cables – without which the world would be plunged into chaos. So when one of Putin’s most senior political allies, Dmitry Medvedev, declared that Moscow now considers them a legitimate target, it’s a threat to be taken seriously.</p>
<p>But – as maritime security expert Christian Bueger of the University of Copenhagen writes – subsea cables are the <a href="https://theconversation.com/ukraine-war-kremlins-threat-to-interfere-with-undersea-data-cables-may-be-bluster-but-must-be-taken-seriously-208125">backbone of the contemporary digital economy</a>. Almost all of our internet connections depend on them. And a number of “chokepoints” exist in places such as the English Channel and the Red Sea, which would be extremely vulnerable to sabotage, as would islands such as Ireland, which does not have terrestrial connections as backup. </p>
<p>Bueger stresses that we must take the security of these cables – as well as other maritime infrastructure such as wind farms, power cables, hydrogen pipelines and carbon storage projects – very seriously indeed, and make them the focus of a global strategy to prevent a potential disaster.</p>
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Read more:
<a href="https://theconversation.com/ukraine-war-kremlins-threat-to-interfere-with-undersea-data-cables-may-be-bluster-but-must-be-taken-seriously-208125">Ukraine war: Kremlin's threat to interfere with undersea data cables may be bluster, but must be taken seriously</a>
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<h2>Neighbourhood threat</h2>
<p>Medvedev also has habit of popping up from time to time to threaten the use of nuclear weapons against the west. And it goes without saying he learned at his master’s feet. Vladimir Putin announced the other day to let us know he planned to station nuclear warheads in neighbouring Belarus. </p>
<p>Belarus was the first former Soviet bloc country to get rid of its nukes after the collapse of the Soviet Union. But the people there have little say in the matter of whether they want to become a target of retaliation in the (it must be said) unlikely event that the Russian president is unhinged enough to escalate to the use of tactical warheads against Ukraine.</p>
<p>Natalya Chernyshova, a historian of the Soviet Union and Belarus at Queen Mary University of London, has <a href="https://theconversation.com/ukraine-war-russias-threat-to-station-nuclear-warheads-in-belarus-what-you-need-to-know-208136">tracked Belarusian attitudes to Russia and the war in Ukraine</a> and finds a country that is deeply ambivalent about both questions. Not that that matters. Since the late 1990s, the two countries have been what’s known as a “union state” (read, decisions are taken mainly in Moscow). </p>
<p>The longtime dictator of Belarus, Alexander Lukashenko, is thought to do very little without consulting Putin. He had to call in Russian troops in 2020 to keep popular protests at what appeared to be his rigged election to keep him in power.</p>
<p>In a survey taken in March 2023, Chatham House found that 74% of respondents objected to deployment and only 24% were in favour of stationing Russian troops there. And it’s important to remember, writes Chernyshova, that for years – as in Russia – Belarus state media has been banging a relentlessly pro-Moscow drum.</p>
<p>Most likely though, according to the ISW, the plan to ship nuclear warheads and their accompanying troops across into Belarus is simply Putin’s way of taking an ever firmer grip over its unfortunate neighbour.</p>
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<strong>
Read more:
<a href="https://theconversation.com/ukraine-war-russias-threat-to-station-nuclear-warheads-in-belarus-what-you-need-to-know-208136">Ukraine war: Russia's threat to station nuclear warheads in Belarus – what you need to know</a>
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<h2>Prospects for peace?</h2>
<p>While all this has been going on, a delegation of African leaders spearheaded by South Africa’s Cyril Ramaphosa have visited both Zelensky and Putin in their various capitals to plead for the two sides to come together and talk. This, writes Stefan Wolff, an international relations expert from the University of Birmingham, has a lot to do with Africa’s concern at the prospect that Moscow may decide to <a href="https://theconversation.com/ukraine-war-failed-african-peace-mission-underscores-need-for-more-powerful-political-and-military-pressure-on-putin-208162">call a halt to the grain and fertiliser deal</a> that has kept prices down and helped stave off starvation.</p>
<p>But, as Wolff notes, like so many attempts to bring the two sides together, the red lines in Moscow and Kyiv are irreconcilable and will remain so as long as Russian troops remain in Ukraine, killing people and shelling innocent civilians. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ukraine-war-failed-african-peace-mission-underscores-need-for-more-powerful-political-and-military-pressure-on-putin-208162">Ukraine war: failed African peace mission underscores need for more powerful political and military pressure on Putin</a>
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<p><em>Ukraine Recap is available as a fortnightly email newsletter. <a href="https://theconversation.com/uk/newsletters/ukraine-recap-114?utm_source=TCUK&utm_medium=linkback&utm_campaign=UK+Newsletter+Ukraine+Recap+2022+Mar&utm_content=WeeklyRecapBottom">Click here to get our recaps directly in your inbox.</a></em></p><img src="https://counter.theconversation.com/content/208323/count.gif" alt="The Conversation" width="1" height="1" />
A selection of the best of our coverage of the conflict from the past fortnight.Jonathan Este, Senior International Affairs Editor, Associate EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2076412023-06-15T14:21:17Z2023-06-15T14:21:17ZUkraine war: offensive use of satellite tech a sign of how conflict is increasingly moving into space<figure><img src="https://images.theconversation.com/files/532213/original/file-20230615-15-j1neil.jpg?ixlib=rb-1.1.0&rect=14%2C306%2C4977%2C3323&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Harvepino/Nasa/Shutterstock</span></span></figcaption></figure><p>As Ukraine’s counteroffensive got underway, there were <a href="https://www.understandingwar.org/backgrounder/russian-offensive-campaign-assessment-june-14-2023">credible reports</a> of advances into territory previously occupied by Russian troops. Each day brings news of small gains, a village liberated here and a village liberated there.</p>
<p>But Ukraine’s military commander will know there are much tougher tests to come. <a href="https://www.telegraph.co.uk/world-news/2023/06/11/russian-fortifications-ukraine-counter-offensive-war/">Recently published satellite pictures</a> reveal the extent of Russian defensive lines – which are considerable, the result of months of planning and preparation for the counteroffensive. The big question is whether their planners can take advantage of eyes in the sky to formulate a strategy.</p>
<p>Ukraine possesses no satellites of their own, but nonetheless space technology has played a key role in supporting its operations. When the invasion began Ukraine was quick to <a href="https://twitter.com/FedorovMykhailo/status/1498664494301650950?s=20&t=-IXrxEPkyi4flNG0vXQATA">call for assistance</a> in tracking and targeting Russian troops. Several <a href="https://www.cnet.com/science/space/ukraine-asks-commercial-satellite-operators-for-help-tracking-russian-troops/">commercial satellite providers</a> have since volunteered to provide help. </p>
<p>Ukraine’s ability to call on the assistance of commercial satellites is thought to have <a href="https://jamestown.org/program/russias-space-satellite-problems-and-the-war-in-ukraine/">given them the edge</a> over Russia’s array of <a href="https://ridl.io/satellites-of-stagnation/">purpose-built military satellites</a>. Russian military satellites are made for battlefield applications and their cameras lack the resolution of those used for industrial purposes. </p>
<p>Russian equipment is also less effective when dealing with <a href="https://www.rferl.org/a/russia-satellites-ukraine-war-gps/31797618.html">cloud cover and darkness</a>. As a result, Russian forces can see less of the battlefield. </p>
<p>The use of space assets has many benefits, not least of which is being able to see what is happening. Ukrainian forces can benefit from <a href="https://www.geospatialworld.net/blogs/geoint-osint-comes-off-age-of-ukraine-conflict/">high-resolution imagery</a> of events on the ground, often in near real-time. </p>
<p>When on the defensive, this has allowed Ukraine to rapidly react to Russian actions, tracking their troop movements and allowing time to respond to any attempted advances.</p>
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<p>Satellites have also <a href="https://ecfr.eu/article/lessons-for-the-west-russias-military-failures-in-ukraine/">helped expose</a> Russian problems with logistics, as well as detect the construction of <a href="https://www.rferl.org/a/ukraine-crimea-satellite-russia-targets/32176768.html">new military infrastructure</a>.</p>
<h2>Navigating Russia’s defences</h2>
<p>Now that Ukrainian forces are advancing, satellite images can again play a pivotal role. As satellite images have revealed, Russia has built an extensive network of <a href="https://www.csis.org/analysis/ukraines-offensive-operations-shifting-offense-defense-balance">trenches, fortifications and minefields</a>, reinforced around areas of <a href="https://www.reuters.com/graphics/UKRAINE-CRISIS/COUNTEROFFENSIVE/mopakddwbpa/">particular strategic importance</a>. </p>
<p>If Ukraine is to <a href="https://unherd.com/2023/06/the-plan-behind-ukraines-counteroffensive/">achieve its objective</a> of severing Russia’s land bridge to Crimea, it will have to contend with these formidable defences. </p>
<p>Publicly available images show how Russian defences are structured. Russian engineering represents a <a href="https://rusi.org/explore-our-research/publications/special-resources/meatgrinder-russian-tactics-second-year-its-invasion-ukraine">series of challenges</a> that will be difficult to overcome.</p>
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<p>But, just as importantly, satellites provide a picture of what is taking place <a href="https://www.economist.com/graphic-detail/2023/05/25/satellite-data-show-ukraines-forces-are-testing-russias-defences">behind the lines</a>, permitting strikes against headquarters and logistic hubs. This was a key factor in the preparation for Ukraine’s successful counteroffensives last autumn.</p>
<p>Given the situation on the ground, a likely Ukrainian approach is to continue to leverage their information advantage, probing these defences with repeated feints and forcing Russian forces to respond. Having a clear picture of Russia’s defensive array will give Kyiv’s commanders in the field both important insights into Russia’s strategy and provide crucial real-time information about where and when to mount its attacks.</p>
<p>Satellite images also provide a range of other insights relevant to the conflict, and ultimately, its aftermath. Imagery available to the public has proved useful in <a href="https://interactive.satellitetoday.com/via/november-2022/how-satellite-imagery-magnified-ukraine-to-the-world/">addressing disinformation</a> and shaping public perceptions of the conflict. These images will also furnish <a href="https://www.nbcnews.com/science/science-news/ukraine-satellites-war-crimes-rcna26291">vital evidence</a> of Russian war crimes when the conflict ends.</p>
<h2>War in space</h2>
<p>At the moment, Ukraine’s access to commercial satellites gives it an advantage over Russia – not only in terms of imagery, but also in other areas like communications and targeting. Naturally, Russia would like to address this advantage.</p>
<p>Russia has not only <a href="https://www.bbc.co.uk/news/technology-60796079">hacked</a> into western satellites, but threatened to <a href="https://www.csis.org/analysis/russia-threatens-target-commercial-satellites">shoot them down</a>. While it certainly has the capability to both disrupt and <a href="https://www.nationalgeographic.com/science/article/russia-just-blew-up-a-satellite-heres-why-that-spells-trouble-for-spaceflight">even destroy</a> space-based assets, the situation is too complex for a direct approach. </p>
<p>Not only are the satellites in question commercial assets, but they do not belong to Ukraine. Any attack runs the risk of expanding the conflict. </p>
<p>Moscow has stressed that commercial satellites represent <a href="https://www.themoscowtimes.com/2022/10/27/russia-says-us-satellites-assisting-ukraine-are-legitimate-targets-a79208">legitimate targets</a>, but a physical attack against these assets would be <a href="https://ieeexplore.ieee.org/abstract/document/9131731">unprecedented</a>. It would open up Russian space infrastructure to attack in response. What is more, this would potentially place Russia on course for a direct conflict with the US and other nations. </p>
<p>But this in itself raises a key issue. Access to this sort of <a href="https://defensescoop.com/2023/05/09/commercial-satellite-imagery-services-included-in-new-1-2b-ukraine-security-assistance-package/">capability is expensive</a>, and Ukraine must rely on partners such as the US to pay for its use of commercial space platforms. The Kremlin may hope it can continue in its strategy of attempting to degrade the relationship between Ukraine and its western allies. </p>
<p>Russia can additionally attempt to jam or disrupt satellites by electronic means, where possible. While Russia does have limitations, it is capable of adaptation, and satellite operators will need to remain vigilant. </p>
<p>Writing in the <a href="https://www.ft.com/content/9abc0a33-9aec-4159-921e-44ef5c70aca4">Financial Times newspaper</a> late last year, former Nato secretary general, Anders Fogh Rasmussen, wrote:</p>
<blockquote>
<p>This is the first major conflict where both sides have been heavily reliant on space-based capabilities. It will not be the last.</p>
</blockquote>
<p>The use of satellites and GPS technology to pinpoint targets has shown how important this technology is. But it is also vulnerable, as anti-satellite action is being <a href="https://www.researchgate.net/profile/Alexandros-Kolovos/publication/368806976_Commercial_Satellites_in_Crisis_and_War_The_Case_of_the_Russian-Ukrainian_Conflict/links/63fa0f6a0d98a97717b9684e/Commercial-Satellites-in-Crisis-and-War-The-Case-of-the-Russian-Ukrainian-Conflict.pdf#page=32">integrated into the tactical battlefield</a>. </p>
<p>Working out how to manage, develop and safeguard space technology will be an increasing focus among military planners.</p><img src="https://counter.theconversation.com/content/207641/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Morris 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 Ukraine conflict shows the importance of space technology in modern warfare.Christopher Morris, Teaching Fellow, School of Strategy, Marketing and Innovation, University of PortsmouthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2032022023-04-20T15:06:20Z2023-04-20T15:06:20ZOuter space: Rwanda and Nigeria sign an accord for more responsible exploration – why this matters<figure><img src="https://images.theconversation.com/files/520291/original/file-20230411-22-7wlsxu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">NASA’s Artemis I Space Launch System rocket, with the Orion capsule attached, launches at NASA's Kennedy Space Center on November 16, 2022 in Cape Canaveral, Florida. </span> <span class="attribution"><span class="source">Kevin Dietsch/Getty Images</span></span></figcaption></figure><p><em>In 2020, the United States announced a framework for the private exploitation of space resources. It consists of practical principles to guide exploration, science and commerce in outer space. The <a href="https://www.nasa.gov/specials/artemis-accords/index.html">Artemis Accords</a> are intended to make space activity responsible, transparent, safe, peaceful and sustainable. Nigeria and Rwanda <a href="https://www.nasa.gov/feature/nasa-welcomes-nigeria-rwanda-as-newest-artemis-accords-signatories">signed</a> the accords on 14 December 2022, becoming the 22nd and 23rd countries, respectively, and the first African countries to do so. Nigerian space law and policy scholar, Anne Agi, explains why they signed and what the potential impacts could be.</em></p>
<h2>What are the Artemis Accords?</h2>
<p>The Artemis Accords are principles, guidelines and best practices shared by the US and other governments participating in NASA’s <a href="https://www.nasa.gov/artemisprogram">Artemis Program</a>, which aims to explore the Moon and send astronauts to Mars. The accords seek to advance international cooperation and peace in space activities, for the benefit of humanity. </p>
<p>The first countries to sign up were the US, Australia, Canada, Italy, Japan, Luxembourg, Ukraine, the UK and the United Arab Emirates. South Korea was the first to sign during the President Joe Biden administration.</p>
<p>Key principles of the Artemis Accords include respect for the sovereignty of celestial bodies, interoperability of systems, transparency and predictability of space activities. </p>
<p>They also deal with things like cooperation in emergency situations, registration of space objects, managing orbital debris and public release of scientific data. </p>
<p>The principles recognise the right of all countries to explore and use outer space peacefully. They prohibit weapons of mass destruction in outer space, and protect long-term sustainability of outer space activities.</p>
<h2>How does membership benefit countries?</h2>
<p>Signing the Artemis Accords is a precondition to be involved in the Artemis <a href="https://www.nasa.gov/specials/artemis/">programme</a>. </p>
<p>As signatories, Nigeria and Rwanda are demonstrating their commitment to safe, sustainable use of outer space. This should have multiple benefits.</p>
<p>It boosts their international standing as responsible members of the space-faring community. It makes their space sectors more appealing to international investors and shows they are committed to exploiting space to advance their economies.</p>
<p>Being a signatory can build capacity in the space industry. This is through encouraging African nations to budget appropriately and develop policies and infrastructure for space activity. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/africa-has-ambitious-goals-for-2063-plans-for-outer-space-hold-the-key-to-success-180636">Africa has ambitious goals for 2063: plans for outer space hold the key to success</a>
</strong>
</em>
</p>
<hr>
<p>The Accords will allow Africa to benefit from shared knowledge and technological resources. Partner nations are required to publicly describe their policies and plans.</p>
<p>Space exploration has numerous <a href="https://theconversation.com/africa-and-space-the-continent-starts-to-look-skyward-41336">applications</a>, from satellite technology to <a href="https://theconversation.com/earth-observation-data-offers-hope-for-africas-wetlands-111123">Earth observation</a>. These can drive innovation and create new industries. For example, in Rwanda, <a href="https://africanews.space/in-conversation-with-clarisse-iribagiza-ceo-of-hehe/">DMM.HeHe</a> is using space technology for logistics and to connect farmers to customers. The company incorporates remote sensing in agriculture to predict yield by monitoring farm operations, educating farmers on their harvest and planning their logistics to increase productivity. And <a href="https://techbuild.africa/xy-analytics-machine-precision-livestock-farming/">XY Analytics</a>, a South African agricultural technology startup, offers satellite-enabled pasture optimisation and herd management to cattle farmers.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/starlink-spacexs-new-internet-service-could-be-a-gamechanger-in-africa-200746">Starlink: SpaceX's new internet service could be a gamechanger in Africa</a>
</strong>
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<p>Being a signatory also enables a country to participate at events where decisions on outer space are made.</p>
<p>African space nations can use their advantageous position in the Accords to advance national interests in the space industry. They can weigh in on issues like militarisation, spy and reconnaissance satellites, space trash, and the right to use resources. Nigeria and Rwanda could get help from other signatories in the event of space related attacks. Nigeria could join forces with global giants for wider and more effective broadband coverage, and invite experts from Artemis partner nations to collaborate on initiatives like the National Centre for Artificial Intelligence and Robotics. </p>
<p>Nigeria and Rwanda’s accession to the Artemis Accords could have a positive impact on Africa as a whole and address the gap between Africa and other regions in terms of space exploration and use. </p>
<p>The Accords require partners to make their scientific data available to the public. With access to this data, Nigeria and Rwanda will not need to reinvent the wheel when they are ready to launch their satellites or engage in space travel.</p>
<p>The principles result in reduced costs for space activity. </p>
<p>Artemis acknowledges that member states can use space resources, but there is no obligation to do so in a way that benefits all member states. African nations must push for a sharing formula for mined space resources to be shared among signatories to the Accords.</p>
<p>Finally, Nigeria and Rwanda could in due course become partners in the effort to return astronauts to the Moon and eventually to Mars. The African continent has yet to send an astronaut into space. </p>
<h2>Does membership present any challenges?</h2>
<p>The <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introliability-convention.html">Outer Space Treaty and Liability Convention</a>, a UN backed law, requires a launching state – a country responsible for launching a particular space craft – to be held internationally liable for damage caused by their space objects. </p>
<p>The Artemis Accord allows states to acquire the status of a launching state for any space object launched by other signatory states for the purposes of the Artemis programme. So African states could find themselves liable for damage done by another partner nation. </p>
<p>African countries should also prepare for financial and other consequences in the event of US cancellation or withdrawal from the Accords.</p>
<p>Some nations have <a href="https://theconversation.com/artemis-accords-why-many-countries-are-refusing-to-sign-moon-exploration-agreement-148134">opposed</a> the Artemis Accords. Russia and China argue that they are overly focused on American and commercial interests and amount to a power grab by the US and its allies. This may affect Nigeria’s and Rwanda’s interests and foreign relationships as they relate to China. </p>
<p>China has made large financial and infrastructural investments in numerous African nations. It has for several years collaborated with Nigeria and <a href="https://apnews.com/article/ethiopia-abiy-ahmed-environment-east-africa-china-37baf3f65b352e8b6480b43246ccbf77">Ethiopia</a> on building practical satellite projects. African nations must be careful not to be perceived as being ungrateful or overly aligned with the US, as they have indeed benefited largely from China.</p><img src="https://counter.theconversation.com/content/203202/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anne Uruegi Agi is affiliated with LEARNSPACE FOUNDATION </span></em></p>As signatories, Nigeria and Rwanda are demonstrating their commitment to safe, sustainable use of outer space. This should have multiple benefits.Anne Uruegi Agi, Law lecturer , University of Calabar Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2022042023-04-05T19:18:01Z2023-04-05T19:18:01ZHow can we make the space sector more sustainable?<figure><img src="https://images.theconversation.com/files/518447/original/file-20230330-17-2bzlma.jpeg?ixlib=rb-1.1.0&rect=20%2C0%2C1897%2C1474&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An artist's impression of the 30,000 or so space debris orbiting around the Earth.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/hopeful_in_nj/3273279798">Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>When talking about space, one might think about the stars one sees at night or a good sci-fi film. But space is also crowded with satellites, spacecrafts and astronauts, whose missions can last anywhere from several days to months. Meanwhile, <a href="https://www.geospatialworld.net/prime/how-many-satellites-orbiting-earth/">8,216 unmanned satellites</a> revolve around Earth’s orbits to improve our daily lives. Communication satellites contribute to enhancing Internet access in regions deprived of infrastructure (so-called “white areas”); meteorology satellites have become essential for weather forecasts, while navigation satellites (including GPS) are crucial for current and future transportation needs such as automatic driving vehicles.</p>
<p>Technological advances in the sector have unlocked many new business opportunities. The industry can now launch constellations of thousand satellites to reach corners of the earth as it had never before (e.g., <a href="https://theconversation.com/space-junk-astronomers-worry-as-private-companies-push-ahead-with-satellite-launches-137572">Starlink</a>), while new markets such as space mining and space tourism are steadily growing. National champions (including the <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2022/09/09">United States</a> and <a href="https://www.elysee.fr/elysee/module/19326/fr">France</a>) have also framed the space sector as a top economic priority. It is thought the technological benefits accrued by companies such as SpaceX, Blue Origin or OneWeb, launched by billionaires such as Elon Musk, will also be able to trickle down to non-space sectors such as the energy or freight industries.</p>
<h2>Issues for sustainable space</h2>
<p>For all these benefits, civil society appears increasingly concerned about the sector’s ecological footprint.</p>
<p>The first main issue to tackle is <a href="https://theconversation.com/space-debris-what-can-we-do-with-unwanted-satellites-40736">space debris</a> which are defunct human-made objects in Earth orbit that no longer serve a useful function. These objects include non-operating satellites, abandoned parts of launch vehicles, which carry satellites or spacecraft into space, decommissioned satellites, and even debris resulting from the collision between space objects. In practice, this means more than <a href="https://www.esa.int/Space_Safety/Space_Debris/ESA_s_Space_Environment_Report_2022">30,000 harmful space debris</a> and 3,364 non-operating satellites could collide into an estimated 4,859 active operating satellites, with catastrophic implications for our daily lives in sectors spanning transport and security to finance.</p>
<p>Some space activities could also impact the Earth’s environment, including air, water and soil pollution, and outer-space contaminations. Take, for example, the rising popularity of space tourism. Given <a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021EF002612">soot from spacecrafts currently warms up the Earth</a> at a rate that is 500 times greater than that released by planes, there is growing anxiety over the sector’s associated greenhouse gas emissions and toxic substances. As a result, the debate over space activities cannot be the prerogative of the space community alone.</p>
<p>In an attempt to resolve these issues, our <a href="https://intellectdiscover.com/content/journals/10.1386/tmsd_00063_1">recent research</a> has identified three promising working avenues:</p>
<ul>
<li><p>Collaboration</p></li>
<li><p>Green space technology</p></li>
<li><p>Policies aiming at sustainable development</p></li>
</ul>
<h2>Tailor solutions for sustainable space</h2>
<p>The collaboration needs to be carried out <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/radm.1254">between five key parties</a>: governments, academia, the industry, civil society, and environmental players such as NGOs. Nevertheless, while the industry has already developed an awareness of the issues at stake, the input of academic institutions has yet to be clarified. In particular, academia could provide new ideas in the areas of debris identification and removal, space traffic management, space situational awareness, and in-orbit servicing.</p>
<p>The second solution consists in developing green space technology that would emit less greenhouse gas emissions and other hazardous chemical substances. According to <a href="https://www.esa.int/Space_Safety/Clean_Space/Green_technologies">the European Space Agency</a>, these green technologies could minimise the energy consumption throughout the entire life-cycle of a space mission, save up on resources, while also minimising toxic substances to protect human well-being and biodiversity.</p>
<p>Green space solutions to investigate include space traffic management, in-orbit servicing and active debris removal on the one hand. When it comes to the spacecrafts themselves, scientists should also start to imagine greener propulsion, cleaner fuels, and alternatives to toxic material. For example, following the path of SpaceX, all launch vehicle manufacturers are also considering reusable launchers that will reduce CO<sub>2</sub> gas emission in a life cycle.</p>
<p>The final solution consists in developing policies that can at once encourage space commercialisation and enhance sustainable policy regime. One instance of this are green innovation policies assisting low-carbon small and medium enterprises. It will be important to align these policies with the <a href="https://www.un.org/sustainabledevelopment/">17 pillars of Sustainable Development Goals (SDGs) established by the United Nations</a>. To achieve this agenda, some indicators are emerging such as space sustainability rating and ESG (environment, social and governance).</p>
<p>We think that we are still on time to solve the two main issues in sustainable space: space debris and the sector’s overall ecological impact on Earth. However, space organisations cannot remain idle awaiting that “space shame” – a space version of <em>flight shame</em> (from the original Swedish concept of <a href="https://theconversation.com/flight-shaming-how-to-spread-the-campaign-that-made-swedes-give-up-flying-for-good-133842"><em>flygskam</em></a>) in the aviation sector – propels them into action.</p><img src="https://counter.theconversation.com/content/202204/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nonthapat Pulsiri has received funding from the SIRIUS Chair.</span></em></p><p class="fine-print"><em><span>Victor Dos Santos Paulino has received funding from the SIRIUS Chair.</span></em></p>How might the space industry reduce its ecological footprint and better manage the debris it leaves in its wake?Nonthapat Pulsiri, Chercheur post-doctorant en stratégie, innovation et entrepreneuriat, Chaire Sirius, TBS EducationVictor Dos Santos Paulino, Professeur associé en management de l'innovation et stratégie, Chaire Sirius, TBS EducationLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2024002023-03-29T19:26:53Z2023-03-29T19:26:53ZAirplanes face a growing risk of being hit by uncontrolled re-entries of rockets used to launch satellites<figure><img src="https://images.theconversation.com/files/517907/original/file-20230328-21-a6pz02.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3996%2C1944&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A SpaceX Falcon 9 rocket carrying Starlink satellites launches on Aug. 19, 2022. The Falcon 9 is a reusable rocket and its re-entry is controlled after launch, reducing debris.</span> <span class="attribution"><span class="source">(Malcolm Denemark/Florida Today via AP)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/airplanes-face-a-growing-risk-of-being-hit-by-uncontrolled-re-entries-of-rockets-used-to-launch-satellites" width="100%" height="400"></iframe>
<p>On May 11, 2020 a deadly threat flew from Los Angeles to New York City in under nine minutes. It was a <a href="https://www.nbcnews.com/science/space/chinese-rocket-debris-passed-over-n-y-c-l-it-n1206311">20-tonne Chinese Long March 5B rocket body passing around 60 miles overhead</a>. </p>
<p>Just 15 minutes later, the rocket body re-entered the atmosphere and broke into pieces, including a <a href="https://www.forbes.com/sites/jonathanocallaghan/2020/05/12/parts-of-a-chinese-rocket-may-have-fallen-on-an-african-village/">12-metre-long pipe that crashed into a village in the Ivory Coast</a>.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1260222397350887425"}"></div></p>
<p>The rocket body had completed its mission and been abandoned in orbit, left to return to the surface in an uncontrolled way. It posed an indiscriminate threat to people across the globe — on the ground, at sea, and in aircraft in flight. <a href="https://www.newscientist.com/article/2327922-10-per-cent-chance-falling-rockets-will-hit-someone-in-next-decade/">The probability of a lethal impact was very small</a>, but the consequences could have been severe.</p>
<h2>Weighing cost against risk</h2>
<p>At the time, the Federal Aviation Administration (FAA) decided not to close U.S. airspace — denying planes permission to fly within a designated area — along the rocket body’s path. The timeframe for making such a decision was very short and fraught with uncertainty, while the economic costs to airlines and passengers were certain and large.</p>
<p>In circumstances like these, decision-makers have to weigh the economic costs against taking no action but accepting a small probability of casualties. The FAA chose the latter.</p>
<p>On Nov. 4, 2022, Spain and France closed parts of their airspace for 40 and 60 minutes respectively, as <a href="https://www.theguardian.com/world/2022/nov/04/spanish-airspace-partially-closed-as-chinese-rocket-debris-falls-to-earth">another Chinese Long March 5B rocket body was due to re-enter the atmosphere uncontrolled</a>. The rocket body passed harmlessly overhead, before breaking up over the Pacific Ocean. </p>
<p><a href="https://spacenews.com/long-march-5b-stage-reenters-over-pacific-ocean-after-forcing-airspace-closures-in-europe/">More than 300 flights were disrupted</a> by the Spanish airspace closure alone, costing airlines and passengers millions of Euros.</p>
<p>Which approach was correct? Nobody likes delays, yet we all expect airlines and regulators to put safety first. Nevertheless, why are aviation agencies being forced to make these decisions at all?</p>
<h2>No confirmed instances</h2>
<p>An aircraft in flight could be seriously damaged by just 300 grams of space debris impacting an engine, windshield or other critical surface. Although there are no confirmed instances of space debris hitting an aircraft in flight, in 1996 the windscreen of a Boeing 757 was cracked by <a href="https://aerospaceamerica.aiaa.org/features/dodging-debris/">an unknown object while flying at 31,500 feet</a>. </p>
<p>In 2013, another Boeing 757 had one side of <a href="https://www.independent.co.uk/news/world/asia/chinese-passenger-jet-makes-emergency-landing-after-being-hit-by-ufo-unidentified-foreign-object-at-26-000-feet-8654040.html">its nose-cone punched in by an unidentified object while flying at 26,000 feet</a>. Bird strikes were unlikely in these instances.</p>
<p>There’s no need for any of us to worry. The probability of an airplane being struck by space debris is extremely small — much smaller than a <a href="https://www.faa.gov/airports/airport_safety/wildlife/faq">bird strike</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a photograph showing a rocket taking off in the distance while a crowd of people watch" src="https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.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">People watch the Long March 5B Y3 carrier rocket lift off from the Wenchang Space Launch Center in southern China on July 24, 2022. Authorities warned of potential danger to aircraft and ships.</span>
<span class="attribution"><span class="source">(Zhang Liyun/Xinhua via AP, File)</span></span>
</figcaption>
</figure>
<p>But even very small probabilities can have severe consequences that justify regulatory action. In 2021, the AstraZeneca COVID-19 vaccine was linked to <a href="https://www.ema.europa.eu/en/news/astrazenecas-covid-19-vaccine-ema-finds-possible-link-very-rare-cases-unusual-blood-clots-low-blood">a very small risk of blood clots — a total of 222 cases among 34 million people</a>, or 0.0007 per cent. </p>
<p>A number of countries responded by curtailing and, in the case of the U.S., not licensing the use of AstraZeneca, <a href="https://www.yalemedicine.org/news/coronavirus-vaccine-blood-clots">thus favoring more expensive MRNA vaccines</a> .</p>
<p>Today, two factors combine to increase the probability of an airplane being struck by space debris: increasing air traffic and increasing uses of space. COVID-19 aside, <a href="https://www.icao.int/about-icao/Pages/annual-reports.aspx">the number of airline flights each year has doubled since the millennium</a>. </p>
<p>In just the last four years the number of active and defunct satellites in low Earth orbit has also doubled, <a href="https://planet4589.org/space/gcat/data/derived/currentcat.html">from approximately 3,000 to more than 8,000</a>.</p>
<h2>Controlled versus uncontrolled</h2>
<p>Satellites are launched using rockets, and while some rocket bodies are brought back to Earth in a controlled manner, <a href="https://doi.org/10.1016/j.actaastro.2021.03.030">many are simply abandoned in orbit</a>.</p>
<p>Uncontrolled re-entries occur because objects orbiting at low enough altitudes still feel the effects of the uppermost portions of Earth’s atmosphere, creating a drag that ensures an eventual re-entry. Predicting these re-entries is very difficult due to a <a href="http://iaass.space-safety.org/wp-content/uploads/sites/24/2021/12/Making-Space-Safe-and-Sustainable-A4-v1-3.pdf">myriad of factors</a> that include variations in the atmosphere itself.</p>
<p>In contrast, a controlled re-entry is performed by using an engine burn that directs the rocket body to a remote area of ocean or a recovery zone. Some fuel must be retained in the rocket body for this purpose, and the engines must be able to reignite.</p>
<p>Yet many operators still <a href="https://doi.org/10.1016/j.jsse.2019.02.001">choose to use uncontrolled re-entries</a>, presumably to avoid the additional costs associated with technological upgrades and extra fuel. </p>
<p>Even SpaceX, an industry leader in technology development, sometimes abandons <a href="https://everydayastronaut.com/ses-18-ses-19-falcon-9-block-5/">the second stages of its rockets after lifting satellites destined for geosynchronous orbit</a>. In 2016, two pressure vessels — each the size of a washing machine — from one such stage reached the ground intact, <a href="https://spaceflight101.com/falcon-9-jcsat-16/spacex-rocket-parts-rain-down-over-indonesia/">landing in Indonesia</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/OhBw5yaR_SU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A controlled re-entry of the European Space Agency’s automated transfer vehicle Jules Verne in Sept. 2008.</span></figcaption>
</figure>
<p>Aviation bodies are taking notice, <a href="https://www.icao.int/secretariat/SecretaryGeneral/Documents/Addresses%20and%20Messages/20230217_SG-SPEECH-SpaceDerbisWorkshop.pdf">including the International Civil Aviation Organization</a> and <a href="https://www.alpa.org/-/media/ALPA/Files/pdfs/news-events/letters/2021/0514-icao-fang-liu-rocket.pdf?la=en">the Air Line Pilots Association</a>. </p>
<p>In March 2023, the <a href="http://outerspaceinstitute.ca/">Montréal Recommendations on Aviation Safety and Uncontrolled Space Object Reentries</a> were released. The recommendations were compiled by international experts, including the Inspector General of the French Space Agency and the Chief of Space Safety in the U.S. Department of the Air Force.</p>
<p>Recognizing that the “use of space by any single state has global implications, with risks potentially exported from launching states to other states,” the recommendations call on states to “establish requirements to avoid uncontrolled re-entries of space objects.”</p>
<p>Will it take a major accident, such as a catastrophic strike to an airplane, before public concern forces governments to require that all rocket bodies be brought back to Earth in a controlled manner?</p>
<h2>Successful policies</h2>
<p>We’ve been here before. In the 1970s, a growing risk to oceans from oil spills led <a href="https://www.jstor.org/stable/24113126">to calls for a requirement for double hulls on tankers</a>. The shipping industry, concerned about increased costs, was able to stifle these efforts — until 1989, when <a href="https://darrp.noaa.gov/oil-spills/exxon-valdez">the Exxon Valdez spilled roughly 11 million gallons of oil into Alaska’s Prince William Sound</a>.</p>
<p>Suddenly, the issue of oil spills was a matter of public concern, and after the National Transportation Safety Board concluded that a double hull would <a href="https://www.ntsb.gov/investigations/AccidentReports/Reports/MAR9004.pdf">have substantially reduced if not eliminated the spill</a>, the U.S. government required <a href="https://response.restoration.noaa.gov/about/media/final-farewell-oil-tankers-single-hulls.html">all new tankers calling at U.S. ports to have double hulls</a>. </p>
<p>This unilateral move prompted the International Maritime Organization to amend the International Convention for the Prevention of Pollution from Ships in 1992 to require double hulls on new tankers. And, through further amendments in 2001 and 2003, to <a href="http://www.imo.org/en/OurWork/Environment/Pages/constructionrequirements.aspx">accelerate the retirement of single-hulled tankers</a>. </p>
<p>The 1992 amendment has since been ratified by 150 nations <a href="http://www.imo.org/en/About/Conventions/Pages/StatusOfConventions.aspx">representing 98 per cent of the world’s shipping tonnage</a>.</p>
<p>One of the most informative aspects of this precedent is that the U.S. adopted a double-hull requirement before any other nation, and this move then prompted successful multilateral law-making.</p>
<p>Today, uncontrolled rocket body re-entries are another international safety issue where the U.S. could lead.</p>
<p>The FAA licenses the majority of the world’s space launches and regulates one of the largest aviation industries. It is perfectly positioned to spur international change — before an airplane full of passengers is struck from the sky.</p>
<p><em>This is a corrected version of a story originally published on March 29. The earlier story said that the Montréal Recommendations on Aviation Safety and Uncontrolled Space Object Reentries was published in 2022 instead of 2023.</em></p><img src="https://counter.theconversation.com/content/202400/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Byers receives funding from the Canada Research Chairs Program, Social Sciences and Humanities Research Council of Canada, Natural Sciences and Engineering Research Council of Canada, New Frontiers in Research Fund, and the Department of National Defence. He is affiliated with the Outer Space Institute and the Salt Spring Forum. </span></em></p><p class="fine-print"><em><span>Aaron Boley receives funding from the Canada Research Chairs Program, Natural Sciences and Engineering Research Council of Canada, New Frontiers in Research Fund, and the Department of National Defence. He is affiliated with the Outer Space Institute. </span></em></p>Rockets used to launch satellites fall back to Earth, and as their number grows, the risk faced by people living on the ground — or flying in airplanes — increases.Michael Byers, Professor, Political Science, University of British ColumbiaAaron Boley, Associate Professor, Physics and Astronomy, University of British ColumbiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2020472023-03-20T19:23:17Z2023-03-20T19:23:17ZSatellites and space junk may make dark night skies brighter, hindering astronomy and hiding stars from our view<figure><img src="https://images.theconversation.com/files/516258/original/file-20230320-183-8rlygz.jpg?ixlib=rb-1.1.0&rect=15%2C0%2C1680%2C1050&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.esa.int/ESA_Multimedia/Images/2013/04/Distribution_of_debris">ESA</a></span></figcaption></figure><p>Since time immemorial, humans around the world have gazed up in wonder at the night sky. The starry night sky has not only inspired countless works of music, art and poetry, but has also played an important role in timekeeping, navigation and agricultural practices in <a href="https://doi.org/10.1017/s1743921310004783">many traditions</a>.</p>
<p>For many cultures, the night sky, with its stars, planets and the Milky Way, is considered <a href="https://doi.org/10.1016/j.polgeo.2020.102218">just as important</a> a part of the natural environment as the forests, lakes and mountains below. Countless people around the world gaze at the night sky: not only amateur and professional astronomers, but also casual observers who enjoy looking up at the stars to contemplate our place in the cosmos.</p>
<p>However, the night sky is changing. Not only is ground-based light pollution <a href="https://theconversation.com/night-skies-are-getting-9-6-brighter-every-year-as-light-pollution-erases-stars-for-everyone-199383">increasing rapidly</a>, but <a href="https://astronomy.com/magazine/news/2023/03/megaconstellations-are-changing-the-night-sky">growing numbers of satellites</a> and space debris in orbit around Earth are also impacting the night sky.</p>
<p><a href="https://academic.oup.com/mnrasl/article/504/1/L40/6188393">Earlier research</a> showed that satellites and space debris may increase the overall brightness of the night sky. In <a href="https://www.nature.com/articles/s41550-023-01904-2">a new paper</a> in Nature Astronomy, my colleagues and I applied this knowledge to predicting the performance of a major astronomical sky survey. We found this phenomenon may make the survey 7.5% less efficient and US$21.8 million more expensive.</p>
<h2>A brighter sky</h2>
<p>As a cultural astronomer, I am interested in the role of the night sky in <a href="https://tpt.pbslearningmedia.org/resource/cultural-cosmos-a-cultural-astronomers-view-video/northern-nights-starry-skies/">cultural traditions</a> around the world. In particular, I am interested in how <a href="http://spica.org.uk/index.php/2019/11/09/the-night-sky-in-the-lives-of-amateur-and-professional-astronomers/">light pollution</a> and increasing satellite numbers affect different communities.</p>
<p>The number of satellites in orbit is growing rapidly. Since 2019, the number of functional satellites in orbit has <a href="https://www.ucsusa.org/resources/satellite-database">more than doubled</a> to <a href="https://www.space-track.org/auth/login">around 7,600</a>. The increase is mostly due to SpaceX and other companies <a href="https://www.science.org/content/article/satellite-swarms-are-threatening-night-sky-creating-new-zone-environmental-conflict">launching large groups of satellites</a> to provide high-speed internet communications around the world. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/516260/original/file-20230320-16-z160am.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Starlink satellites already leave streaks on astronomical photographs – but growth in satellites and debris will make the whole sky brighter.</span>
<span class="attribution"><a class="source" href="https://noirlab.edu/public/images/ann21021c/">Rafael Schmall / NOIRLab</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>By the end of this decade, we estimate, there may be 100,000 satellites in orbit around the Earth. Collisions that generate space debris are <a href="https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/JA083iA06p02637">more likely</a> as space fills with new satellites. Other sources of debris include the <a href="https://doi.org/10.1016/j.actaastro.2023.02.043">intentional destruction of satellites</a> in space warfare tests. </p>
<p>Increasing numbers of satellites and space debris reflect ever more sunlight towards the night side of Earth. This will almost certainly change the appearance of the night sky and <a href="https://aas.org/sites/default/files/2020-08/SATCON1-Report.pdf">make it harder for astronomers</a> to do research.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/thousands-of-satellites-are-polluting-australian-skies-and-threatening-ancient-indigenous-astronomy-practices-173840">Thousands of satellites are polluting Australian skies, and threatening ancient Indigenous astronomy practices</a>
</strong>
</em>
</p>
<hr>
<p>One way satellites impact astronomy is by appearing as moving points of light, which show up as streaks across astronomers’ images. Another is by increasing <a href="https://academic.oup.com/mnrasl/article/504/1/L40/6188393">diffuse night sky brightness</a>. This means all the satellites that are too dim or small to be seen individually, as well as all the small bits of space debris, still reflect sunlight, and their collective effect is to make the night sky appear less dark.</p>
<h2>Hard times for astronomers</h2>
<p>In <a href="https://doi.org/10.1038/s41550-023-01904-2">our research</a>, we present the first published calculations of the aggregate effects of satellites and space debris in low-Earth orbit on major ground-based astronomy research facilities. </p>
<p>We looked at the effect on the planned <a href="https://www.lsst.org/science">large-scale survey of the night sky</a> to be carried out at the Vera Rubin Observatory starting in 2024. We found that, by 2030, reflected light from objects in low-Earth orbit will likely increase the diffuse background brightness for this survey by at least 7.5% compared to an unpolluted sky.</p>
<p>This would diminish the efficiency of this survey by 7.5% as well. Over the ten-year lifetime of the survey, we estimate this would add some US$21.8 million to the total project cost. </p>
<hr>
<p>
<em>
<strong>
Read more:
<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">Starlink, Amazon and others are racing to fill the sky with bigger satellites to deliver mobile coverage everywhere on Earth</a>
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<p>Brighter night skies mean longer exposures through telescopes are needed to see distant objects in the cosmos. This will mean that for projects with a fixed amount of observing time, less science will be accomplished, and there will be increased competition for telescope access.</p>
<p>In addition, brighter night skies will also reduce the detection limits of sky surveys, and dimmer objects may not be detected, resulting in missed research opportunities. </p>
<p>Some astrophysical events are rare and if researchers are unable to view them when they occur, there might not be an opportunity to easily see a given event again during a survey’s operational period. One example of faint objects is near-Earth objects – comets and asteroids in orbits close to Earth. Brighter night skies make it more likely such potentially hazardous objects may remain undetected.</p>
<h2>A dramatic and unprecedented tranformation</h2>
<p>Increases in diffuse night sky brightness will also change how we see the night sky with the unaided eye. As the human eye cannot resolve individual small objects as well as a telescope can, an increase in satellites and space debris will create an even greater increase in the apparent brightness of the night sky. (When using a telescope or binoculars, one would be able to make out more of the dimmer satellites individually.)</p>
<p>The projected increase in night sky brightness will make it increasingly difficult to see fainter stars and the Milky Way, both of which are important in <a href="https://doi.org/10.48550/ARXIV.2008.05266">various cultural traditions</a>. Unlike “ground-based” light pollution (which tends to be the worst near large cities and heavily populated areas), the changes to the sky will be visible from essentially everywhere on Earth’s surface.</p>
<figure class="align-center zoomable">
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<figcaption>
<span class="caption">There may be 100,000 satellites in orbit around Earth by 2030.</span>
<span class="attribution"><a class="source" href="https://noirlab.edu/public/images/ann22005a/">M Lewinsky / NOIRLab</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Our models give us a conservative lower limit for a likely increase in night sky brightness. If numbers of satellites and space debris continue to grow at the expected rate, the impacts will be even more pronounced.</p>
<p>As we note in our paper, “we are witnessing a dramatic, fundamental, and perhaps semi-permanent transformation of the night sky without historical precedent and with limited oversight”. Such a transformation will have profound consequences for professional astronomy as well as for anyone who wishes to view an unpolluted night sky.</p><img src="https://counter.theconversation.com/content/202047/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jessica Heim 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>Tens of thousands of satellites orbiting Earth will hamper astronomers’ efforts to study the Universe and spot dangerous asteroids, as well as brightening the sky and hiding stars from the rest of us.Jessica Heim, PhD researcher, University of Southern QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1981402023-03-14T12:24:44Z2023-03-14T12:24:44ZHow to use free satellite data to monitor natural disasters and environmental changes<figure><img src="https://images.theconversation.com/files/514756/original/file-20230310-14-ffq8d1.jpg?ixlib=rb-1.1.0&rect=851%2C251%2C1541%2C1099&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Over 8,000 satellites are orbiting Earth today, capturing images like this, of the Louisiana coast.</span> <span class="attribution"><a class="source" href="https://earthobservatory.nasa.gov/world-of-change/WaxLake">NASA Earth Observatory</a></span></figcaption></figure><p>If you want to track changes in the Amazon rainforest, see the full expanse of a hurricane or figure out where people need help after a disaster, it’s much easier to do with the view from a satellite orbiting a <a href="https://aerospace.csis.org/aerospace101/earth-orbit-101">few hundred miles above Earth</a>.</p>
<p>Traditionally, access to satellite data has been limited to researchers and professionals with expertise in remote sensing and image processing. However, the increasing availability of open-access data from government satellites such as <a href="https://landsat.gsfc.nasa.gov/">Landsat</a> and <a href="https://sentinels.copernicus.eu/">Sentinel</a>, and free cloud-computing resources such as <a href="https://aws.amazon.com/earth/">Amazon Web Services</a>, <a href="https://earthengine.google.com/">Google Earth Engine</a> and <a href="https://planetarycomputer.microsoft.com/">Microsoft Planetary Computer</a>, have made it possible for just about anyone to gain insight into environmental changes underway. </p>
<p>I <a href="https://wetlands.io/">work with geospatial big data</a> as a professor. Here’s a quick tour of where you can find satellite images, plus some free, fairly simple tools that anyone can use to create time-lapse animations from satellite images.</p>
<p>For example, state and urban planners – or people considering a new home – can watch over time <a href="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif">how rivers have moved</a>, construction crept into wildland areas or <a href="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif">a coastline eroded</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A squiggly river moves surprisingly quickly over time." src="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=352&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=352&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=352&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=442&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=442&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508816/original/file-20230208-16-ktgkpl.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=442&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Landsat time-lapse animations show the river dynamics in Pucallpa, Peru.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NASA Landsat</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Animation shows the shoreline shrinking." src="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=349&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=349&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=349&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=439&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=439&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508818/original/file-20230208-15-lbcw9x.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=439&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A Landsat time-lapse shows the shoreline retreat in the Parc Natural del Delta, Spain.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NASA Landsat</span></span>
</figcaption>
</figure>
<p>Environmental groups can monitor deforestation, the effects of climate change on ecosystems, and how other human activities like irrigation are <a href="https://images.theconversation.com/files/508817/original/file-20230208-23-o026h9.gif">shrinking bodies of water</a> like <a href="https://earthobservatory.nasa.gov/world-of-change/AralSea">Central Asia’s Aral Sea</a>. And disaster managers, aid groups, scientists and anyone interested can monitor natural disasters such as <a href="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif">volcanic eruptions</a> and <a href="https://images.theconversation.com/files/508822/original/file-20230208-14-3xtadg.gif">wildfires</a>.</p>
<figure class="align-center ">
<img alt="The lake, created by damming the river, has shrunk over time." src="https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=367&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=367&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=367&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=461&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=461&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514741/original/file-20230310-142-kyqos5.gif?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">GOES images show the decline of the crucial Colorado River reservoir Lake Mead since the 1980s and the growth of neighboring Las Vegas.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NOAA GOES</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A volcanic eruption bursts into view." src="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=352&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=352&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=352&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=442&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=442&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508821/original/file-20230208-16-151a1t.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=442&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 GOES satellite time-lapse shows the Hunga Tonga volcanic eruption on Jan. 15, 2022.</span>
<span class="attribution"><span class="source">Qiusheng Wu, NOAA GOES</span></span>
</figcaption>
</figure>
<h2>Putting Landsat and Sentinel to work</h2>
<p>There are over <a href="https://www.geospatialworld.net/prime/business-and-industry-trends/how-many-satellites-orbiting-earth">8,000 satellites orbiting the Earth</a> today. You can see a live map of them at <a href="https://www.keeptrack.space/">keeptrack.space</a>.</p>
<p>Some transmit and receive radio signals for communications. Others provide global positioning system (GPS) services for navigation. The ones we’re interested in are Earth observation satellites, which collect images of the Earth, day and night.</p>
<p><strong>Landsat:</strong> The longest-running Earth satellite mission, <a href="https://landsat.gsfc.nasa.gov/">Landsat</a>, has been collecting imagery of the Earth since 1972. The latest satellite in the series, <a href="https://www.usgs.gov/landsat-missions/landsat-9">Landsat 9</a>, was launched by NASA in September 2021.</p>
<p>In general, Landsat satellite data has a spatial resolution of about 100 feet (about 30 meters). If you think of pixels on a zoomed-in photo, each pixel would be 100 feet by 100 feet. Landsat has a temporal resolution of 16 days, meaning the same location on Earth is imaged approximately once every 16 days. With both Landsat 8 and 9 in orbit, we can get a global coverage of the Earth <a href="https://www.mdpi.com/1424-8220/20/22/6631">once every eight days</a>. That makes comparisons easier.</p>
<p><a href="https://www.usgs.gov/landsat-missions/landsat-data-access">Landsat data</a> has been freely available to the public since 2008. During the <a href="https://en.wikipedia.org/wiki/2022_Pakistan_floods">Pakistan flood of 2022</a>, scientists used Landsat data and free cloud-computing resources to determine the flood extent and <a href="https://share.gishub.org/pakistan_floods/">estimated the total flooded area</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Images show how the flood covered about a third of Pakistan." src="https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=489&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=489&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508723/original/file-20230207-31-kvunlf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=489&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Landsat satellite images showing a side-by-side comparison of southern Pakistan in August 2021 (one year before the floods) and August 2022 (right)</span>
<span class="attribution"><span class="source">Qiusheng Wu, NASA Landsat</span></span>
</figcaption>
</figure>
<p><strong>Sentinel:</strong> <a href="https://sentinels.copernicus.eu/">Sentinel</a> Earth observation satellites were launched by the European Space Agency (ESA) as part of the <a href="https://www.copernicus.eu/en">Copernicus program</a>. Sentinel-2 satellites have been collecting optical imagery of the Earth since 2015 at a spatial resolution of 10 meters (33 feet) and a temporal resolution of 10 days.</p>
<p><strong>GOES:</strong> The images you’ll see most often in U.S. weather forecasting come from NOAA’s Geostationary Operational Environmental Satellites, or <a href="https://www.goes.noaa.gov/">GOES</a>. They orbit above the equator at the <a href="https://www.nesdis.noaa.gov/current-satellite-missions/currently-flying/geostationary-satellites">same speed Earth rotates</a>, so they can provide continuous monitoring of Earth’s atmosphere and surface, giving detailed information on weather, climate, and other environmental conditions. <a href="https://www.goes-r.gov/multimedia/dataAndImageryImagesGoes-16.html">GOES-16</a> and <a href="https://www.goes-r.gov/multimedia/dataAndImageryImagesGoes-17.html">GOES-17</a> can image the Earth at a spatial resolution of about 1.2 miles (2 kilometers) and a temporal resolution of five to 10 minutes.</p>
<figure class="align-center ">
<img alt="Animation showing swirling clouds off the coast and the long river of moisture headed for California." src="https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=353&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=353&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=353&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=444&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=444&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514739/original/file-20230310-142-1ln3m3.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=444&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A GOES satellite shows an atmospheric river arriving on the West Coast in 2021.</span>
<span class="attribution"><span class="source">Qiusheng Wu, GOES</span></span>
</figcaption>
</figure>
<h2>How to create your own visualizations</h2>
<p>In the past, creating a Landsat time-lapse animation of a specific area required extensive data processing skills and several hours or even days of work. However, nowadays, free and user-friendly programs are available to enable anyone to create animations with just a few clicks in an internet browser.</p>
<p>For instance, I created an <a href="https://huggingface.co/spaces/giswqs/Streamlit">interactive web app</a> for my students that anyone can use to generate time-lapse animations quickly. The user zooms in on the map to find an area of interest, then draws a rectangle around the area to save it as a GeoJSON file – a file that contains the geographic coordinates of the chosen region. Then the user uploads the GeoJSON file to the web app, chooses the satellite to view from and the dates and submits it. It takes the app about 60 seconds to then produce a time-lapse animation.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/VVRK_-dEjR4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How to create satellite time-lapse animations.</span></figcaption>
</figure>
<p>There are several other useful tools for easily creating satellite animations. Others to try include <a href="https://jdbcode.github.io/Snazzy-EE-TS-GIF/">Snazzy-EE-TS-GIF</a>, an Earth Engine App for creating Landsat animations, and <a href="https://planetarycomputer.microsoft.com/docs/overview/explorer/">Planetary Computer Explorer</a>, an explorer for searching and visualizing satellite imagery interactively.</p><img src="https://counter.theconversation.com/content/198140/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Qiusheng Wu receives funding from NASA. He is an Amazon Visiting Academic and a Google Developer Export (GDE) for Earth Engine. </span></em></p>Time-lapse animations that once took days to create are now easy to build with publicly available satellite images and free online tools.Qiusheng Wu, Assistant Professor of Geography and Sustainability, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.