tag:theconversation.com,2011:/nz/topics/european-space-agency-esa-8592/articlesEuropean Space Agency (ESA) – The Conversation2024-02-08T13:21:28Ztag:theconversation.com,2011:article/2223072024-02-08T13:21:28Z2024-02-08T13:21:28ZA new generation of spaceplanes is taking advantage of the latest in technology<figure><img src="https://images.theconversation.com/files/572455/original/file-20240131-25-t35ou5.jpeg?ixlib=rb-1.1.0&rect=5%2C0%2C1911%2C1281&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dream Chaser would ferry cargo, and eventually crew, to low-Earth orbit.</span> <span class="attribution"><a class="source" href="https://images.nasa.gov/details/AFRC2017-0124-015">Ken Ulbrich / NASA</a></span></figcaption></figure><p><a href="https://www.nasa.gov/space-shuttle/">Nasa’s space shuttle</a> operated in low-Earth orbit for 30 years before its retirement in 2011. However, the US space agency’s <a href="https://www.nasa.gov/humans-in-space/orion-spacecraft/">replacement for this vehicle, Orion</a>, returned to the conical capsule design familiar from the Apollo missions. This was because Nasa intended that this newer craft be used for exploring targets in deep space, such as the Moon.</p>
<p>But in recent years, we have seen a return of the spaceplane design. <a href="http://news.bbc.co.uk/1/hi/sci/tech/8601172.stm">Since 2010</a>, the US Space Force (and formerly the US Air Force) has been <a href="https://www.spaceforce.mil/News/Article-Display/Article/3628417/united-states-space-force-launches-seventh-x-37b-mission/#:%7E:text=KENNEDY%20SPACE%20CENTER%2C%20Fla.,Space%20Center%20Launch%20Complex%2039A.">launching a robotic spaceplane called the X-37B</a> into low Earth orbit on classified missions. China has its own <a href="https://www.space.com/china-space-plane-depoyed-mystery-objects">military spaceplane called Shenlong</a>. </p>
<p>This year could see a test flight of the company Sierra Space’s <a href="https://www.sierraspace.com/dream-chaser-spaceplane/">Dream Chaser</a> – the first commercial spaceplane capable of orbital flight. If all goes well, the vehicle could be used to resupply the International Space Station (ISS) with cargo and, eventually, crew. </p>
<p>Spaceplanes can fly or glide in the Earth’s atmosphere and land on runways rather than using parachutes to land in water or flat ground like capsules. They’re also more manoeuvrable as the spacecraft reenters the atmosphere, increasing the area of the Earth’s surface where landing is possible from a specific re-entry point. </p>
<p>Spaceplanes also allow a gentler but longer flight path during re-entry and a softer landing, which is easier on crew and cargo than capsules, which can land with a thump. A runway also allows ground support crews and infrastructure to be ready at the landing location.</p>
<h2>Cost and complexity</h2>
<p>But spaceplanes are more complex and heavier than an equivalent capsule. The winged body shape poses a particular challenge for designing thermal protection systems (TPS) – the heat-resistant materials that protect the craft from scorching temperatures on re-entry. These additional costs mean it’s impractical to design a spaceplane for a single flight. They need to be used again and again to be viable.</p>
<figure class="align-center ">
<img alt="X-37B." src="https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The US Space Force’s X-37B carries no crew, and its missions are classified.</span>
<span class="attribution"><a class="source" href="https://www.spaceforce.mil/Multimedia/Photos/igphoto/2003113618/">Staff Sgt. Adam Shanks / US Space Force</a></span>
</figcaption>
</figure>
<p>There has been interest in spaceplanes from the earliest days of human spaceflight. A military spaceplane project called <a href="https://apps.dtic.mil/sti/citations/ADA303832">Dyna-Soar</a> was started in the US in 1957, then cancelled just after construction started. The vehicle was sophisticated for its time, built using a metal alloy that is able to withstand high temperatures and featuring a heat shield on the front that could be detached after it returned from space, so that the pilot could see clearly as he was landing.</p>
<p>The space shuttle, which entered service in 1981, was the first operational spaceplane. It was supposed to launch more often than it did and have <a href="https://www.popularmechanics.com/space/rockets/a36304153/nasa-space-shuttle/">greater reusability</a> but it turned out that extensive refurbishment was required between launches. It did, however, demonstrate the ability to return astronauts and large cargo from orbit.</p>
<p>Other space agencies invested in the 1980s and 1990s, in Europe, with <a href="https://www.esa.int/About_Us/ESA_history/History_Hermes_spaceplane_1987">the Hermes spaceplane</a>, and Japan, with <a href="https://www.flightglobal.com/japan-stops-work-on-hope-x-spaceplane-/33798.article">the HOPE vehicle</a>. Both programmes were cancelled in large part because of cost. The Soviet Union developed its own <a href="https://airandspace.si.edu/stories/editorial/soviet-buran-shuttle-one-flight-long-history">shuttle-like vehicle called Buran</a>, which successfully flew to space once in 1988. The programme was cancelled after the collapse of the Soviet Union.</p>
<h2>Feeling the heat</h2>
<p>Spaceplanes have specific requirements for the final part of their journeys – as they return from space. <a href="https://www.faa.gov/sites/faa.gov/files/about/office_org/headquarters_offices/avs/III.4.1.7_Returning_from_Space.pdf">During atmospheric re-entry</a>, they are heated to over one thousand degrees Celsius as they travel at hypersonic speeds of over seven kilometres per second – more than 20 times the speed of sound. A blunt nose design (where the edge of the spacecraft is rounded) is an ideal shape because it reduces build-up of heat at the foremost part of the vehicle.</p>
<figure class="align-center ">
<img alt="Space shuttle, STS-132" src="https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">On launch, the space shuttle was attached to the side of a large external propellant tank.</span>
<span class="attribution"><a class="source" href="https://images.nasa.gov/details/sts132-s-047">NASA / JSC</a></span>
</figcaption>
</figure>
<p>Even so, the expected temperatures experienced by the craft can still be as high as 1600°C, necessitating a thermal protection system on the outside of the vehicle. <a href="https://www.centennialofflight.net/essay/Evolution_of_Technology/TPS/Tech41.htm">The space shuttle TPS</a> included ceramic tiles that were especially heat resistant and a reinforced carbon-carbon matrix that was capable of withstanding temperatures as high as 2400°C. </p>
<p>The <a href="https://www.nasa.gov/history/20-years-ago-remembering-columbia-and-her-crew/">loss of the Columbia shuttle</a> during re-entry in 2003, causing the deaths of seven astronauts, was the result of a breach in the TPS on the leading edge of the wing. This resulted from a piece of insulating foam flying off the shuttle’s external tank during Columbia’s launch and hitting the wing. </p>
<p>This foam issue was recurrent with the shuttle because of the way it launched on the side of the external propellant tank. But newer spaceplane designs will fly atop conventional rockets, where falling foam isn’t a problem.</p>
<p>An effective TPS remains vital for the <a href="https://www.nasa.gov/wp-content/uploads/2016/08/2015_nasa_technology_roadmaps_ta_9_entry_descent_landing_final.pdf">future success of spaceplanes</a>, as are systems that monitor the TPS performance in real time.</p>
<h2>Current vehicles</h2>
<p>There are currently two operating spaceplanes, one Chinese and one American, that can reach orbit. Little information is available on China’s Shenlong, but <a href="https://www.boeing.com/defense/autonomous-systems/x37b">the US military’s X-37B</a> is better known. Weighing close to five tonnes at launch, the nine metre-long, uncrewed vehicle is launched using a conventional rocket and lands autonomously on a runway at the end of its mission. </p>
<p>The X-37B’s TPS uses tiles similar to the shuttle over the lower surface with a lower-cost alternative to reinforced <a href="https://en.wikipedia.org/wiki/Reinforced_carbon%E2%80%93carbon">carbon-carbon</a> called Tufroc, developed for the X37B, on the nose and leading edges.</p>
<p>They should soon be joined by Dream Chaser, which was was developed by the company to carry both cargo and astronauts, but Nasa wants to prove its safety before carrying people by using it to carry cargo to the space station first. The ability to return comparatively fragile cargo to the surface because of a softer landing is a key capability. The tiles that protect Dream Chaser are made from silica, and <a href="https://www.nasaspaceflight.com/2023/09/dream-chaser-tps/">each has a unique shape</a> matched to the area on the vehicle they are designed to protect.</p>
<figure class="align-center ">
<img alt="Dream Chaser" src="https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Dream Chaser undergoing evaluation at Nasa’s Neil Armstrong Test Facility.</span>
<span class="attribution"><a class="source" href="https://twitter.com/NASAglenn/status/1753108059004825754/photo/1">NASA</a></span>
</figcaption>
</figure>
<h2>Future developments</h2>
<p>There is continued interest in spaceplanes because of their ability to return crew and cargo to a runway. The demand for this capability is limited now. But if the costs of launching to space continue falling and an expansion of industry in space raises demand, they will become an increasingly viable alternative to capsules.</p>
<p>Longer term, there is also potential for spaceplanes capable of reaching orbit after taking off from a runway. The challenges of developing these single-stage-to-orbit (SSTO) vehicles is considerable. However, <a href="https://www.colorado.edu/faculty/kantha/sites/default/files/attached-files/70494-96876_-_kyle_borg_-_may_8_2015_853_am_-_borg_matula_skylon_report.pdf">concepts such as the Skylon vehicle</a> are leading to technical developments that could eventually support development of an SSTO craft.</p>
<p>For the foreseeable future, spaceplanes look promising for the following reasons: new design techniques, improved materials for the TPS, advanced computer modelling and simulation tools for optimising different aspects of design and flight parameters and continuous improvements in propulsion systems. </p>
<p>Given that several governments, space agencies, and private companies worldwide are investing heavily in spaceplane research and development, we could see a future where flights with these vehicles become routine.</p><img src="https://counter.theconversation.com/content/222307/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>Spaceplanes seemed out of favour when the shuttle was retired in 2011; they now seem to be making a comeback.Oluwamayokun Adetoro, Senior Lecturer, Mechanical and Aerospace Engineering, Brunel University LondonJames Campbell, Reader, Brunel University LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2221732024-01-29T16:38:10Z2024-01-29T16:38:10ZNasa’s Mars helicopter Ingenuity has ended its mission – its success paves the way for more flying vehicles on other planets and moons<figure><img src="https://images.theconversation.com/files/571847/original/file-20240129-15-v0glwl.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2270%2C1360&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Ingenuity helicopter on Mars.</span> <span class="attribution"><a class="source" href="https://mars.nasa.gov/resources/27421/ingenuity-at-two-years-on-mars/">NASA/JPL-Caltech/ASU/MSSS</a></span></figcaption></figure><p>It is difficult to emphasise the significance of the milestone surpassed by Nasa’s Mars helicopter, Ingenuity. </p>
<p>The little (1.8kg) helicopter <a href="https://mars.nasa.gov/resources/25608/nasas-perseverance-rover-lands-successfully-on-mars/">touched down with the Perseverance rover in 2021</a>. On 25 January, Nasa announced that the flying vehicle <a href="https://www.nasa.gov/news-release/after-three-years-on-mars-nasas-ingenuity-helicopter-mission-ends/">had to perform an emergency landing</a> which damaged one of its rotors and ended its mission. </p>
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<p>This reminds us that space exploration is still difficult to do. But Ingenuity’s three years on Mars proved that powered, controlled flight on Mars was possible. </p>
<p>The little helicopter lasted for far longer than had been planned and flew higher and further than many had envisaged. Beyond this Martian experiment, the rotorcraft’s success paves the way for other missions using flying vehicles to explore planets and moons.</p>
<p>The first landings on the Moon were static. The year 1969 was probably the most important one for space exploration, when <a href="https://www.nasa.gov/mission/apollo-11/">Apollo 11</a> and <a href="https://www.nasa.gov/mission/apollo-12/">Apollo 12</a> brought astronauts to the lunar surface, but 1970 was the year for planetary exploration. </p>
<p>In 1970, we had the <a href="https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1970-060A">first soft landing on another planet</a>, Venus. The first robotic sample delivered to Earth from the Moon. And the first robot rover to drive around another body (also the Moon). </p>
<p>Since then, following over 50 years of planetary exploration and technology development, there have only been a small number of successful surface missions, and even fewer were able to move. Venus was visited by a dozen static landers between 1970 and 1985, and never again. </p>
<h2>From rovers to helicopters</h2>
<p>Mars was only successfully landed on three times between 1971 and 1976 before the <a href="https://mars.nasa.gov/mars-exploration/missions/pathfinder/">Pathfinder lander</a> and Sojourner rover arrived in 1997. The European Huygens spacecraft then landed on Titan, the moon of Saturn, in 2005. </p>
<p>These attempts at reaching the surface are rare, extremely difficult, and, historically, the landers were hardly ever mobile. Yet the Nasa <a href="https://mars.nasa.gov/mer/mission/overview/">Mars rovers Spirit, Opportunity</a>, <a href="https://mars.nasa.gov/msl/home/">Curiosity</a>, and <a href="https://mars.nasa.gov/mars2020/">Perseverance</a> have all exceeded their designs and travelled further and further.</p>
<p>And Ingenuity flew.</p>
<p>It wasn’t the first spacecraft to fly. Those would be the balloons deployed by the <a href="https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1984-128F">Soviet Vega 1 and 2 missions</a>, which floated over Venus in 1985. But Ingenuity had control, cameras, and connectivity. It took photos of its rover and of Mars from an entirely new perspective. It commanded the world’s attention and captured our hearts.</p>
<p>In Moscow, I had the chance to see models and replicas of the Vega balloons and the first lunar rover. They made a stronger impression on me than the Mars rover twins being used at Nasa’s Jet Propulsion Laboratory (JPL) in California. The Soviet missions were more audacious and different, and they were from generations ago, before my time and long before my career as a planetary scientist.</p>
<p>Ingenuity was audacious, original and completely new. The photos it took, of Perseverance, finding technology discarded from the descent module that carried it down to Mars and of the Martian vistas from a bird’s eye view, were breathtaking. Meanwhile, Perseverance also took videos of Ingenuity flying in the air. Nothing like it had ever seen before.</p>
<figure class="align-center ">
<img alt="CGI image of a silver drone with eight propellers over the Martian surface" src="https://images.theconversation.com/files/571881/original/file-20240129-23-b4r2m2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/571881/original/file-20240129-23-b4r2m2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=380&fit=crop&dpr=1 600w, https://images.theconversation.com/files/571881/original/file-20240129-23-b4r2m2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=380&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/571881/original/file-20240129-23-b4r2m2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=380&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/571881/original/file-20240129-23-b4r2m2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=478&fit=crop&dpr=1 754w, https://images.theconversation.com/files/571881/original/file-20240129-23-b4r2m2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=478&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/571881/original/file-20240129-23-b4r2m2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=478&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">An artist’s impression of the Dragonfly spacecraft in flight.</span>
<span class="attribution"><a class="source" href="https://dragonfly.jhuapl.edu/Gallery/">NASA/Johns Hopkins APL/Steve Gribben</a></span>
</figcaption>
</figure>
<h2>Future flights</h2>
<p>Ingenuity had a rough ride getting there, however. The entire Mars 2020 mission (of Perseverance, Ingenuity and their transport systems) was sudden. </p>
<p>Following Nasa’s withdrawal from the joint European Space Agency ExoMars programme, which included a Mars rover mission, the US space agency started developing one on its own. This rover, later named Perseverance, went from announcement to concept to development and launch in just seven-and-a-half years.</p>
<p>And Ingenuity wasn’t included onboard at first. As an idea, it was proposed late in the development phase of Mars 2020, and faced serious opposition. It added extra complexity, cost, risk and new failure modes. It was also driven by an engineering objective, with the possibility of a little outreach – the opportunity to communicate the mission’s science and engineering to the public – on the side.</p>
<p>Ingenuity wasn’t intended to last for very long. It was designed to prove helicopter flight in the thin Mars atmosphere. It targeted five short flights over a month. Possible outcomes included hard landings, toppling over, losing power if its solar panels were covered in dust, or losing communication when it was far from the rover (this happened several times). </p>
<figure class="align-center ">
<img alt="Large silver balloon being launched in the desert." src="https://images.theconversation.com/files/571874/original/file-20240129-25-1d0l8.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/571874/original/file-20240129-25-1d0l8.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/571874/original/file-20240129-25-1d0l8.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/571874/original/file-20240129-25-1d0l8.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/571874/original/file-20240129-25-1d0l8.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=425&fit=crop&dpr=1 754w, https://images.theconversation.com/files/571874/original/file-20240129-25-1d0l8.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=425&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/571874/original/file-20240129-25-1d0l8.jpeg?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">
<figcaption>
<span class="caption">Aerial robotic balloons, or aerobots, like this Nasa prototype, could one day explore Venus.</span>
<span class="attribution"><a class="source" href="https://www.jpl.nasa.gov/news/jpls-venus-aerial-robotic-balloon-prototype-aces-test-flights">Nasa / JPL-Caltech</a></span>
</figcaption>
</figure>
<p>But it went way beyond expectations, surviving three years on the Martian surface, even through a dusty season, and making 72 flights. Much of its success was aided by the communication network that now exists at Mars. </p>
<p>Ingenuity receives instructions and transmits data to Perseverance, which communicates with a fleet of satellites that include the European ExoMars Trace Gas Orbiter, Nasa’s Maven spacecraft, and the Mars Reconnaissance Orbiter. These, in turn, communicate with two deep space networks on Earth, systems of radio antennas around the world that command and track spacecraft. </p>
<p>It took 50 years of planetary exploration to get here, but already we can see the impact on future exploration that Ingenuity’s mission is having. The next interplanetary rotorcraft will be the <a href="https://dragonfly.jhuapl.edu/">Dragonfly mission to Saturn’s moon Titan</a>. </p>
<p>It will be a very different from Ingenuity. It will weigh about a ton and fly with eight rotors. It is a huge vehicle designed to fly in Titan’s thick atmosphere. </p>
<p>One of the next Red Planet missions will be Mars Sample Return, aiming to collect sample containers of Martian soil being prepared and cached by Perseverance. This has been planned to be carried out with use of a rover, but the success of Ingenuity has led to the idea – and now the development – of <a href="https://mars.nasa.gov/msr/spacecraft/sample-recovery-helicopters/">a helicopter</a> to do that. </p>
<p>The future that Ingenuity has opened up for us is exciting. We’ll see helicopters on Mars and Venus, more balloons on Venus, swimming vehicles under the icy moons of Jupiter and Saturn, and maybe even an aeroplane or two.</p><img src="https://counter.theconversation.com/content/222173/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kevin Olsen in an employee of the University of Oxford and receives funding from the UK Space Agency in support of Mars science.</span></em></p>Among the missions being planned is a huge helicopter drone to explore Saturn’s moon Titan.Kevin Olsen, UKSA Mars Science Fellow, Department of Physics, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2180002023-12-26T19:41:32Z2023-12-26T19:41:32ZFrom the Moon’s south pole to an ice-covered ocean world, several exciting space missions are slated for launch in 2024<figure><img src="https://images.theconversation.com/files/565859/original/file-20231214-25-glo8i8.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4498%2C3003&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">NASA isn't the only space agency with exciting missions to watch for in 2024. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/d5633dd767384229af78233cd6dccb06?ext=true">AP Photo/John Raoux</a></span></figcaption></figure><p>The year 2023 proved to be an important one for space missions, with NASA’s OSIRIS-REx mission <a href="https://www.pbs.org/newshour/science/watch-live-ancient-asteroid-sample-lands-on-earth-in-last-leg-of-nasa-osiris-rex-mission">returning a sample from an asteroid</a> and India’s Chandrayaan-3 mission <a href="https://www.space.com/chandrayaan-3-moon-temperature-lunar-south-pole-first-time">exploring the lunar south pole</a>, and 2024 is shaping up to be another exciting year for space exploration.</p>
<p>Several new missions under NASA’s <a href="https://www.nasa.gov/specials/artemis/">Artemis plan</a> and <a href="https://www.nasa.gov/commercial-lunar-payload-services/">Commercial Lunar Payload Services initiative</a> will target the Moon.</p>
<p>The latter half of the year will feature several exciting launches, with the launch of the Martian Moons eXploration mission in September, Europa Clipper and Hera in October and Artemis II and VIPER to the Moon in November – if everything goes as planned.</p>
<p><a href="https://www.eaps.purdue.edu/people/profile/bramsona.html">I’m a planetary scientist</a>, and here are six of the space missions I’m most excited to follow in 2024.</p>
<h2>1. Europa Clipper</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A spacecraft with two large rectangular panels coming off a small cylinder flies above a brown and white moon, with a brown striped planet in the background." src="https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/563177/original/file-20231204-15-5dr2r5.jpeg?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">Illustration of what the Europa Clipper spacecraft will look like flying by Europa, a moon of Jupiter.</span>
<span class="attribution"><a class="source" href="https://www.jpl.nasa.gov/images/pia24321-europa-clipper-spacecraft-illustration">NASA/JPL-Caltech</a></span>
</figcaption>
</figure>
<p>NASA will launch <a href="https://europa.nasa.gov/">Europa Clipper</a>, which will explore <a href="https://science.nasa.gov/jupiter/moons/europa/">one of Jupiter’s largest moons, Europa</a>. Europa is slightly smaller than Earth’s Moon, with a surface made of ice. Beneath its icy shell, Europa likely harbors a saltwater ocean, which scientists expect contains over twice as much water as all the <a href="https://europa.nasa.gov/why-europa/ingredients-for-life">oceans here on Earth combined</a>.</p>
<p>With Europa Clipper, scientists want to investigate whether Europa’s ocean could be <a href="https://europa.nasa.gov/mission/about/#pre-project-planning-pre-phase-a">a suitable habitat for extraterrestrial life</a>.</p>
<p>The mission plans to do this by flying past Europa <a href="https://www.astronomy.com/science/ask-astro-why-will-europa-clipper-orbit-jupiter-instead-of-europa/">nearly 50 times</a> to study the moon’s icy shell, its surface’s geology <a href="https://doi.org/10.1038/s41467-020-15160-9">and its subsurface ocean</a>. The mission will also look for <a href="https://europa.nasa.gov/news/40/are-water-plumes-spraying-from-europa-nasas-europa-clipper-is-on-the-case/">active geysers</a> spewing out from Europa.</p>
<p>This mission will change the game for <a href="https://theconversation.com/jupiters-moons-hide-giant-subsurface-oceans-two-missions-are-sending-spacecraft-to-see-if-these-moons-could-support-life-203207">scientists hoping to understand ocean worlds</a> like Europa. </p>
<p>The launch window – the period when the mission could launch and achieve its planned route – <a href="https://europa.nasa.gov/mission/timeline/">opens Oct. 10, 2024</a>, and lasts 21 days. The spacecraft will <a href="https://www.nasa.gov/news-release/nasa-awards-launch-services-contract-for-europa-clipper-mission/">launch on a SpaceX Falcon Heavy rocket</a> and arrive at the Jupiter system in 2030.</p>
<h2>2. Artemis II launch</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four people in orange spacesuits stand in a small white room." src="https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/563207/original/file-20231204-17-459f6.jpeg?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 Artemis II astronauts at the launchpad during a ground systems test in September 2023 at Kennedy Space Center.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/general/first-artemis-crew-trains-for-mission-around-moon/">NASA</a></span>
</figcaption>
</figure>
<p>The Artemis program, <a href="https://theconversation.com/who-is-artemis-nasas-latest-mission-to-the-moon-is-named-after-an-ancient-lunar-goddess-turned-feminist-icon-189504">named after Apollo’s twin sister</a> in Greek mythology, is <a href="https://www.nasa.gov/humans-in-space/artemis/">NASA’s plan to go back to the Moon</a>. It will send humans to the Moon for the first time since 1972, including the <a href="https://www.nasa.gov/general/what-is-artemis/">first woman and the first person of color</a>. Artemis also includes plans for <a href="https://www.space.com/rebooting-moon-nasa-artemis-sustainability">a longer-term, sustained presence in space</a> that will prepare NASA for eventually sending people even farther – <a href="https://www.nasa.gov/news-release/new-program-office-leads-nasas-path-forward-for-moon-mars/">to Mars</a>.</p>
<p>Artemis II is the first crewed step in this plan, with <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">four astronauts</a> planned to be on board during the 10-day mission.</p>
<p>The mission builds upon <a href="https://www.nasa.gov/mission/artemis-i/">Artemis I</a>, which sent an uncrewed <a href="https://www.nasa.gov/humans-in-space/orion-spacecraft/">capsule</a> into orbit around the Moon in late 2022.</p>
<p>Artemis II will put the astronauts into orbit around the Moon before returning them home. It is currently planned for <a href="https://phys.org/news/2023-03-nasa-artemis-mission-moon-november.html">launch as early as November 2024</a>. But there is a chance it will get pushed back to 2025, depending on whether all the necessary gear, such as spacesuits and oxygen equipment, <a href="https://www.space.com/artemis-2-humans-moon-orbit">is ready</a>.</p>
<h2>3. VIPER to search for water on the Moon</h2>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/S9Y6n1G5hhc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The VIPER rover to survey water at the south pole of the Moon.</span></figcaption>
</figure>
<p><a href="https://science.nasa.gov/mission/viper/">VIPER</a>, which stands for Volatiles Investigating Polar Exploration Rover, is a robot the size of a golf cart that NASA will use to explore the Moon’s <a href="https://www.nasa.gov/news-release/nasas-artemis-rover-to-land-near-nobile-region-of-moons-south-pole/">south pole</a> in late 2024. </p>
<p><a href="https://www.nasa.gov/solar-system/nasa-replans-clps-delivery-of-viper-to-2024-to-reduce-risk-2/">Originally scheduled for launch in 2023</a>, NASA pushed the mission back to complete more tests on the lander system, which <a href="https://www.astrobotic.com/">Astrobotic</a>, a private company, developed as part of the <a href="https://www.nasa.gov/commercial-lunar-payload-services/">Commercial Lunar Payload Services</a> program.</p>
<p>This robotic mission is designed to search for <a href="https://www.planetary.org/space-missions/viper">volatiles</a>, which are molecules that easily vaporize, like water and carbon dioxide, at lunar temperatures. These materials could provide resources for <a href="https://theconversation.com/scientists-suspect-theres-ice-hiding-on-the-moon-and-a-host-of-missions-from-the-us-and-beyond-are-searching-for-it-216060">future human exploration</a> on the Moon.</p>
<p>The VIPER robot will rely on batteries, heat pipes and radiators throughout its <a href="https://science.nasa.gov/mission/viper/in-depth/">100-day mission</a>, as it navigates everything from the extreme heat of lunar daylight – when temperatures can reach 224 degrees Fahrenheit (107 degrees Celsius) – to the Moon’s <a href="https://www.smithsonianmag.com/science-nature/five-things-to-know-about-nasas-lunar-rover-viper-180978787/">frigid shadowed regions</a> that can reach a mind-boggling -400 F (-240 C).</p>
<p>VIPER’s launch and delivery to the lunar surface is scheduled for <a href="https://www.nasa.gov/solar-system/nasa-replans-clps-delivery-of-viper-to-2024-to-reduce-risk-2/">November 2024</a>.</p>
<h2>4. Lunar Trailblazer and PRIME-1 missions</h2>
<p>NASA has recently invested in a class of small, low-cost planetary missions called <a href="https://soma.larc.nasa.gov/simplex/">SIMPLEx</a>, which stands for Small, Innovative Missions for PLanetary Exploration. These missions save costs by tagging along on other launches as what is called a rideshare, or secondary payload. </p>
<p>One example is the <a href="https://www.planetary.org/space-missions/lunar-trailblazer">Lunar Trailblazer</a>. Like VIPER, Lunar Trailblazer will look for water on the Moon. </p>
<p>But while VIPER will land on the Moon’s surface, studying a specific area near the south pole in detail, Lunar Trailblazer will orbit the Moon, measuring the temperature of the surface and <a href="https://trailblazer.caltech.edu/objectives.html">mapping out the locations of water molecules</a> across the globe. </p>
<p>Currently, Lunar Trailblazer is on track <a href="https://trailblazer.caltech.edu/index.html">to be ready by early 2024</a>.</p>
<p>However, because it is a secondary payload, Lunar Trailblazer’s launch timing depends on the primary payload’s launch readiness. The <a href="https://www.nasa.gov/mission/polar-resources-ice-mining-experiment-1-prime-1">PRIME-1</a> mission, <a href="https://nextspaceflight.com/launches/details/6828">scheduled for a mid-2024 launch</a>, is Lunar Trailblazer’s ride.</p>
<p>PRIME-1 will drill into the Moon – it’s a test run for the kind of drill <a href="https://www.nasa.gov/centers-and-facilities/kennedy/apollo-to-artemis-drilling-on-the-moon/">that VIPER will use</a>. But its launch date will likely depend on whether earlier launches go on time. </p>
<p>An earlier Commercial Lunar Payload Services mission with the <a href="https://www.space.com/intuitive-machines">same landing partner</a> was <a href="https://www.intuitivemachines.com/post/intuitive-machines-im-1-lunar-mission-launch-update">pushed back to February 2024 at the earliest</a>, and further delays could push back PRIME-1 and Lunar Trailblazer.</p>
<h2>5. JAXA’s Martian Moon eXploration mission</h2>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/yiS6NdpEL2A?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The JAXA MMX mission concept to study Phobos and Deimos, Mars’ moons.</span></figcaption>
</figure>
<p>While Earth’s Moon has many visitors – big and small, robotic and crewed – planned for 2024, Mars’ moons Phobos and Deimos will soon be getting a visitor as well. The Japanese Aerospace Exploration Agency, or JAXA, has a robotic mission in development called the <a href="https://www.mmx.jaxa.jp/en/">Martian Moon eXploration, or MMX,</a> planned for launch around September 2024. </p>
<p>The mission’s main science objective is to determine the origin of Mars’ moons. Scientists aren’t sure whether Phobos and Deimos are <a href="https://doi.org/10.1126/science.199.4324.64">former asteroids that Mars captured into orbit with its gravity</a> or if they <a href="https://doi.org/10.1007/s00159-011-0044-6">formed out of debris</a> that was already in orbit around Mars.</p>
<p>The spacecraft will spend three years around Mars conducting <a href="https://doi.org/10.1186/s40623-021-01546-6">science operations</a> to observe Phobos and Deimos. MMX will also land on Phobos’ surface and <a href="https://doi.org/10.1186/s40623-021-01545-7">collect a sample</a> before returning to Earth. </p>
<h2>6. ESA’s Hera mission</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An illustration of two gray asteroids, next to a gold box with two large rectangular panels on either side, and two smaller crafts." src="https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565308/original/file-20231212-25-dpf9ef.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An artist’s conception of the Hera mission to literally measure the impact of NASA’s DART mission in 2022.</span>
<span class="attribution"><a class="source" href="https://www.heramission.space/press-room">ESA</a></span>
</figcaption>
</figure>
<p><a href="https://www.heramission.space/">Hera</a> is a mission by the European Space Agency to return to the Didymos-Dimorphos asteroid system that NASA’s <a href="https://science.nasa.gov/mission/dart/">DART mission</a> visited in 2022.</p>
<p>But DART didn’t just visit these asteroids, <a href="https://theconversation.com/in-a-world-first-nasas-dart-mission-is-about-to-smash-into-an-asteroid-what-will-we-learn-189391">it collided with one of them</a> to test a <a href="https://www.space.com/planetary-defense-explained">planetary defense</a> technique called “kinetic impact.” DART hit Dimorphos with such force that <a href="https://www.nasa.gov/news-release/nasa-confirms-dart-mission-impact-changed-asteroids-motion-in-space/">it actually changed its orbit</a>.</p>
<p>The kinetic impact technique smashes something into an object in order to alter its path. This could prove useful if humanity ever finds a <a href="https://www.livescience.com/what-are-potentially-hazardous-asteroids">potentially hazardous object</a> on a collision course with Earth and needs to redirect it.</p>
<p>Hera will launch in <a href="https://www.esa.int/Space_Safety/Hera">October 2024</a>, making its way in late 2026 to Didymos and Dimorphos, where it will study <a href="https://doi.org/10.3847/PSJ/ac6f52">physical properties of the asteroids</a>.</p><img src="https://counter.theconversation.com/content/218000/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ali M. Bramson receives funding from NASA. </span></em></p>Expect lots of space missions to launch this coming year, with exciting new science to follow.Ali M. Bramson, Assistant Professor of Earth, Atmospheric, and Planetary Sciences, Purdue UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2160332023-11-27T17:08:16Z2023-11-27T17:08:16ZUltratrails, deep dives, outer space: how extraordinary personalities adapt to extreme conditions<p>`Kilian Jornet won the 2022 Ultra-Trail du Mont Blanc (distance 170 kilometres, elevation gain 10,000 metres) in 19 hours 49 minutes and 30 seconds. Stéphanie Gicquel skied 2,045 kilometres in 74 days, crossing Antarctica to reach the South Pole in temperatures as low as -50°. Thomas Pesquet completed a spacewalk lasting 6 hours and 54 minutes, 400 kilometres above the Earth.</p>
<p>These extreme sports athletes deploy excessive efforts to adapt to environmental conditions or exceptional solicitations. Pushing humans beyond their limits is not trivial on a behavioural or psychological level.</p>
<p>So, are these people, who achieve such feats, different from ordinary mortals?</p>
<h2>Environment and extreme performance</h2>
<p>Intense exercise at high altitude, while deep diving, in a polar station, or during a space flight or running an ultra-trail are all extreme activities that are stressful for both the body and the mind.</p>
<p>Indeed, these environments are often characterised by adverse natural conditions (hypoxia, hyperbaria, weightlessness, cold, heat, darkness, etc.), and while environmental factors are the main source of stress, certain situations are also accompanied by social requirements. For example, in Arctic stations or during manned space flights, people live together for several months and are exposed to other forms of “stressors”: prolonged isolation, confinement, boredom, lack of privacy, limited pleasures, interpersonal relationships, and the list goes on. Valery Ryumin, a Russian cosmonaut, <a href="https://www.researchgate.net/publication/348564933_L%E2%80%99humain_dans_l%E2%80%99espace_defis_psychologiques">described these extreme conditions as</a>:</p>
<blockquote>
<p>“All the necessary conditions to perpetrate a murder are met by locking two men in a cabin of 18 by 20 feet… for two months.”</p>
</blockquote>
<p>Depending on the nature of the environment, people can develop different symptoms. At high altitude, for example, some people develop acute mountain sickness, a symptomatology specific to high altitude, characterised by physiological, psychological, behavioural, cognitive, and emotional disorders induced by the hypoxic environmental conditions. This syndrome is linked to both <a href="https://www.researchgate.net/publication/14819979_Effects_of_Altitude_on_Mood_Behaviour_and_Cognitive_Functioning">altitude level and speed of ascent</a> and varies between individuals.</p>
<p>Adapting to these multiple constraints is a challenge, and some people adapt better than others, and sometimes more quickly.</p>
<h2>Influence of personality</h2>
<p>Studies have shown that <a href="https://hal.univ-lorraine.fr/hal-04219768">personality plays an important role in how people adapt to extreme situations</a>.</p>
<p>Moreover, adaptation has been at the heart of the definition of Allport’s personality since the early 20th century. Since the 2000s, personality has even been defined as a characteristic model of adaptation in the habitual way of thinking (cognition), feeling (emotions), and behaving or reacting (behaviour), which tends to remain relatively stable across situations and time.</p>
<p>During a simulated ascent of Everest in a hypobaric chamber, <a href="https://hal.science/hal-04220346">“reserved” and “opportunistic” subjects</a> proved better able to meet the challenge of hypoxia than “open” and “conscientious” subjects.</p>
<p>In professional diving, the assessment of anxiety levels of 16 divers showed that three presented a clinical level of anxiety during the dive. Analysis of their personality showed that they had difficulty controlling themselves and an emotional instability often concomitant with depressive and anxious moods.</p>
<p>The comparison of the personality of a diver who developed <a href="https://api.istex.fr/ark:/67375/WNG-FH738ZLB-J/fulltext.pdf?sid=clickandread">severe anxiety reactions</a>, following the observation of a diver in narcosis, with that of a diver who had no reaction showed that the first was an extrovert with a risk of <a href="https://en.wikipedia.org/wiki/Somatization">somatisation</a>.</p>
<p>In microgravity, the subjects who adapt best to the <a href="https://hal.science/hal-02314127">demanding conditions of a parabolic flight</a> (alternation of hypergravity and microgravity phases) are those who do not like monotony or repetitive or routine tasks. They are more <a href="https://hal.science/hal-03725559">dynamic and proactive in their sensation seeking</a>.</p>
<p>These few studies demonstrate that personality has become a recognised factor which plays a role in adaptation processes in extreme environments.</p>
<h2>Special role of emotional intelligence</h2>
<p><a href="https://doi.org/10.1177/175407391665049">Emotional intelligence</a> can be viewed as a personality characteristic that provides an interesting framework for assessing individual differences in how individuals identify, express, understand, regulate, and use <a href="https://www.cairn.info/les-interventions-en-psychologie-de-la-sante--9782100587780.htm">their own emotions</a> – and those of others.</p>
<p>Extreme sports offer a particularly relevant situation to <a href="https://www.researchgate.net/profile/Michel_Nicolas2">examine this personality trait</a>. Mountain ultra-trails, such as the UTMB (Ultra Trail du Mont Blanc) and the Tor des Géants, are listed among the most gruelling races in the world.</p>
<p>We have demonstrated that athletes with higher emotional intelligence scores reported <a href="https://www.researchgate.net/publication/362372464_Emotional_Intelligence_in_Ultra-Marathon_Runners_Implications_for_Recovery_Strategy_and_Stress_Responses_during_an_Ultra-Endurance_Race">higher recovery rates than athletes with lower scores</a>. The results confirm the positive role of emotional intelligence on an individual’s <a href="https://www.researchgate.net/publication/332359025_Time_courses_of_emotions_experienced_after_a_mountain_ultra-marathon_Does_emotional_intelligence_matter">ability to cope with difficult situations</a> by “recovering” more (resources) to improve their psychological adaptation to these extreme sports. In this perspective, this personality characteristic could protect against stress and improve mental preparation before a competition.</p>
<p>Various studies have suggested that dispositional characteristics, such as the personality of individuals attracted to extreme situations, vary from one environment to another (e.g., Arctic stations, space missions) and can influence adaptation processes. Identifying these personality characteristics could help improve the selection and preparation of individuals to improve their adaptation. By knowing the personality profile, the psychologist can personalise preparation based on the person’s characteristics. For example, some individuals give <a href="https://hal.univ-lorraine.fr/hal-02012277/file/Art%20JP%202%20-%20HAL.pdf">more importance to certain sensory information</a> when choosing how to act. These individuals could be trained to use other sensory modalities to increase their abilities and performance. Another example would be to develop emotional intelligence in extreme sports athletes to help them regulate their emotions and manage their stress in order to maintain or improve performance.</p>
<p>Most studies in extreme environments focus on adjustment disorders and attempt to identify personality characteristics to improve participant selection and training. But from Thomas Pesquet to Kilian Jornet and Stéphanie Gicquel, there is no doubt that extreme sports athletes have exceptional personality characteristics.</p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/485612/original/file-20220920-3440-4oxruu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/485612/original/file-20220920-3440-4oxruu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=250&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485612/original/file-20220920-3440-4oxruu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=250&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485612/original/file-20220920-3440-4oxruu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=250&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485612/original/file-20220920-3440-4oxruu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=314&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485612/original/file-20220920-3440-4oxruu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=314&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485612/original/file-20220920-3440-4oxruu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=314&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em>This article has been published for the <a href="https://www.fetedelascience.fr/">Fête de la Science</a> (which took place on 6-16 October 2023 in mainland France and 10-27 November 2023 in overseas France and internationally) organised in partnership with The Conversation France. This year’s event had the theme “sport and science”.</em></p><img src="https://counter.theconversation.com/content/216033/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Benoît Bolmont has received funding from the Centre National d'Etudes Spatiales.</span></em></p><p class="fine-print"><em><span>Michel Nicolas ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'a déclaré aucune autre affiliation que son organisme de recherche.</span></em></p>Do extreme-sport athletes and explorers have personality traits in common that help them adapt to difficult and surprising conditions?Benoît Bolmont, Professeur en STAPS, Université de LorraineMichel Nicolas, Psychologie, Université de Bourgogne – UBFCLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2140802023-09-21T19:31:10Z2023-09-21T19:31:10ZA Nasa spacecraft is on course to deliver material from an asteroid to Earth – here’s what we could learn<figure><img src="https://images.theconversation.com/files/549564/original/file-20230921-21-76lpa0.png?ixlib=rb-1.1.0&rect=7%2C0%2C2470%2C1406&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.nasa.gov/image-feature/osiris-rex-artists-concept">Nasa/GSFC</a></span></figcaption></figure><p>Around 15 years ago, I was on a <a href="https://www.esa.int/">European Space Agency</a> (Esa) committee, looking at Esa’s strategy for proposed forthcoming space missions. Under consideration was a mission to an asteroid. Over dinner, one of the committee members, an astrophysicist, quizzed me on why we needed to visit one of these objects. </p>
<p>“Nasa has already been to one and the Japanese Space Agency to another. Why do you need to go to another one? They’re all the same aren’t they, just lumps of rock?” My deliberately less-than-polite response was: “Why do astronomers keep wanting to launch more telescopes into space to look at stars? They’re all the same aren’t they, just balls of burning gas?” Our meal continued in frosty silence.</p>
<p>The misconception that asteroids are “just lumps of rock” doesn’t stand up to scrutiny, given the rich harvest of information about asteroid diversity that has come from studying meteorites. Meteorites have taught us about the origin and evolution of the Solar System.</p>
<p>We can measure the ages of meteorites and identify the volatiles – water- and carbon-containing chemicals – that some contain. Volatiles are important for understanding how the building blocks of life were delivered to Earth.</p>
<p>But there are gaps in our knowledge, so we need to study samples directly taken from asteroids – in part because meteorites are often contaminated with compounds from Earth’s environment. This means we can’t always be sure that the volatiles in them came from the asteroid itself, or from Earth. </p>
<p>We also don’t fully understand the relationship of specific meteorite types to different classes of asteroids. This affects our understanding of how volatiles were distributed in the early Solar System and therefore what types of objects could have delivered life’s building blocks to Earth. Hence the need for sample return missions.</p>
<p>On Sunday 24 September, a Nasa spacecraft called Osiris-Rex will fly past Earth and release a capsule containing a haul of dust and rock, which it collected from the surface of the asteroid Bennu in 2020. <a href="https://www.nasa.gov/nasalive">Under the watching eyes</a> of nervous scientists, the capsule will parachute down to a test range in Utah, where it will be retrieved and taken to a sample-curation facility in Houston.</p>
<h2>A rich heritage</h2>
<p>The previous missions mentioned by my astrophysicist colleague were <a href="https://solarsystem.nasa.gov/missions/near-shoemaker/in-depth/#:%7E:text=NASA's%20NEAR%20was%20the%20first,Moon%2C%20Mars%2C%20and%20Venus.">Nasa’s Near-Shoemaker spacecraft</a>, which operated from 1996 to 2001, and the <a href="https://www.isas.jaxa.jp/en/missions/spacecraft/past/hayabusa.html">Japanese space agency’s (Jaxa) Hayabusa mission</a>, which lasted from 2003 to 2005.</p>
<p>Hayabusa brought a few milligrams of material to Earth from the asteroid Itokawa. This allowed us, for the first time, to <a href="https://www.nature.com/articles/s41598-018-30192-4">measure an asteroid’s age</a> –- an important first step in understanding relationships between asteroids and meteorites. </p>
<p>The two most recent asteroid missions are <a href="https://www.isas.jaxa.jp/en/missions/spacecraft/current/hayabusa2.html">Jaxa’s Hayabusa2 mission</a> to the asteroid Ryugu and <a href="https://www.nasa.gov/osiris-rex">Nasa’s Osiris-Rex mission</a> to Bennu. The missions both orbited carbonaceous asteroids, which are rich in volatiles. The orbiting spacecraft helped confirm that Ryugu and Bennu are both water-rich asteroids, with abundant clay and carbonate minerals.</p>
<p>The asteroids have very low densities, suggesting they are objects called “rubble piles”. These contain significant amounts of empty space beneath the surface. Rubble piles formed from debris thrown into space when their bigger parent bodies were hit by another object. The rubble eventually came together to form an asteroid of its own.</p>
<h2>Watery history</h2>
<p>Results from analysis of samples from Ryugu were published in <a href="https://www.nature.com/articles/s41550-021-01550-6">December 2021</a>. They showed that the Ryugu material is very similar in composition to what we call CI meteorites. This is important because CI-related materials are extremely fragile and easily weathered. </p>
<p>As a result, few survive their passage through the Earth’s atmosphere. Now that we can link these rare meteorites more definitively to the class of asteroids Ryugu belongs to, we can expand our understanding of the processes that asteroids went through as they evolved.</p>
<p>In the past, temperatures on some asteroids were just high enough for liquid water to exist. The reaction of the original minerals with water transformed them into more complex mixtures. <a href="https://www.nature.com/articles/s41550-022-01863-0">Evidence suggests the</a> parent asteroid for Ryugu was altered by water between two million and five million years after the Solar System formed.</p>
<p>An important aim of Hayabusa2 was to analyse organics (carbon-containing chemicals) in the sample. There’s overlap between organics and volatiles. Both categories include compounds that could have been important for the origin of life.</p>
<figure class="align-center ">
<img alt="Bennu" src="https://images.theconversation.com/files/549599/original/file-20230921-25-rz88v4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/549599/original/file-20230921-25-rz88v4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/549599/original/file-20230921-25-rz88v4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/549599/original/file-20230921-25-rz88v4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/549599/original/file-20230921-25-rz88v4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/549599/original/file-20230921-25-rz88v4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/549599/original/file-20230921-25-rz88v4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Bennu has been likened to a spinning top in space.</span>
<span class="attribution"><a class="source" href="https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=4857">Nasa's Scientific Visualization Studio</a></span>
</figcaption>
</figure>
<p>There were around 20,000 species (types) of <a href="https://www.science.org/doi/10.1126/science.abn9033">organic compound present in the Ryugu material</a>. This opened our eyes to the sheer complexity of organic compounds in primitive asteroids. </p>
<p>So what’s still left to learn from Bennu? For a start, Osiris-Rex observed bright regions on Bennu’s surface. These were interpreted as <a href="https://www.science.org/doi/full/10.1126/science.abc3557">thick veins of the mineral carbonate</a>. </p>
<p>These were not seen on Ryugu’s surface, although individual grains were found during <a href="https://www.nature.com/articles/s41561-023-01226-y">lab analysis of the samples</a>. This could suggest that alteration by water took place under different conditions on Bennu.</p>
<p>If the ages of alteration by water are different between Ryugu and Bennu, it could mean one of the asteroids underwent a longer process of alteration. This would suggest that their parent bodies formed in different parts of the Solar System.</p>
<p>Like Ryugu, Bennu is very dark. <a href="https://www.science.org/doi/10.1126/science.aaw0422">Analysis of Ryugu from orbit</a> suggested that a process called space weathering may have helped darken and dehydrate the asteroid’s surface. However, lab analysis of the Ryugu sample revealed the presence of clay minerals, showing that water was in fact <a href="https://theconversation.com/material-from-asteroid-ryugu-starts-to-give-up-secrets-of-early-solar-system-173884">abundant on the asteroid</a>. If the same effect is observed for Bennu, there are implications for the search for water on asteroids.</p>
<p>Bennu is recognised as a potentially hazardous asteroid, meaning there is a one in 3,000 chance of it hitting us in 150-200 years’ time.</p>
<p>By the time the global community of planetary scientists has analysed all the available material from Bennu, it is unlikely that any aspect of its formation, evolution and orbital history, composition and components will be unknown, allowing an effective “Earth
rescue” <a href="https://theconversation.com/nasa-is-crashing-a-spacecraft-into-an-asteroid-to-test-a-plan-that-could-one-day-save-earth-from-catastrophe-190888">mission to be launched</a>.</p><img src="https://counter.theconversation.com/content/214080/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Monica Grady is Professor of Planetary and Space Sciences at The Open University. She is Chancellor of Liverpool Hope University and Senior Research Fellow at the Natural History Museum. She receives funding from the Science and Technology Facilities Council and the UK Space Agency. She tweets @MonicaGrady and orbits the Sun as Asteroid (4731) Monicagrady</span></em></p>Missions to asteroids are opening up the secrets of the Solar SystemMonica Grady, Professor of Planetary and Space Sciences, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2107612023-09-19T12:20:32Z2023-09-19T12:20:32ZSpending time in space can harm the human body − but scientists are working to mitigate these risks before sending people to Mars<figure><img src="https://images.theconversation.com/files/545125/original/file-20230828-27-8wodoh.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3649%2C2434&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">With NASA planning more missions to space in the future, scientists are studying how to mitigate health hazards that come with space flight. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/RocketLaunch/45d363b2268349d4a85f5c9f112757e1/photo?Query=space%20launch&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=732&currentItemNo=12&vs=true">AP Photo/John Raoux</a></span></figcaption></figure><p>When <a href="https://www.space.com/record-17-people-in-earth-orbit-at-once">17 people</a> were in orbit around the Earth all at the same time on May 30, 2023, it set a record. With NASA and other federal space agencies planning more manned missions and commercial companies bringing people to space, opportunities for human space travel are rapidly expanding. </p>
<p>However, traveling to space poses risks to the human body. Since NASA wants to send a manned <a href="https://www.nasa.gov/topics/moon-to-mars">mission to Mars</a> in the 2030s, scientists need to find solutions for these hazards sooner rather than later.</p>
<p>As a kinesiologist who works with astronauts, I’ve spent years <a href="https://scholar.google.com/citations?user=KaVh79oAAAAJ&hl=en">studying the effects</a> space can have on the body and brain. I’m also involved in a NASA project that aims to <a href="https://www.nasa.gov/hrp/5-hazards-of-human-spaceflight">mitigate the health hazards</a> that participants of a future mission to Mars might face.</p>
<h2>Space radiation</h2>
<p>The Earth has a protective shield called a <a href="https://science.nasa.gov/heliophysics/focus-areas/magnetosphere-ionosphere">magnetosphere</a>, which is the area of space around a planet that is <a href="https://science.nasa.gov/heliophysics/focus-areas/magnetosphere-ionosphere">controlled by its magnetic field</a>. This shield filters out <a href="https://www.nrc.gov/reading-rm/basic-ref/glossary/cosmic-radiation.html">cosmic radiation</a>. However, astronauts traveling farther than the International Space Station will face continuous exposure to this radiation – equivalent to between <a href="https://www.nasa.gov/analogs/nsrl/why-space-radiation-matters">150 and 6,000 chest X-rays</a>.</p>
<p>This radiation can harm the <a href="https://doi.org/10.1080/26896583.2021.1891825">nervous and cardiovascular systems</a> including <a href="https://doi.org/10.1080/26896583.2021.1891825">heart and arteries</a>, leading to cardiovascular disease. In addition, it can <a href="https://doi.org/10.1080/26896583.2021.1885283">make the blood-brain barrier leak</a>. This can expose the brain to chemicals and proteins that are harmful to it – compounds that are safe in the blood but toxic to the brain.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/e9sN9gOEdG4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The blood-brain barrier keeps compounds flowing through your circulatory system out of your brain.</span></figcaption>
</figure>
<p>NASA is developing technology that can shield travelers on a Mars mission from radiation by building deflecting materials such as Kevlar and polyethylene into <a href="https://www.lockheedmartin.com/en-us/products/astrorad---what-you-wear-in-space-could-save-your-life.html">space vehicles and spacesuits</a>. Certain diets and supplements <a href="https://enterade.com/">such as enterade</a> may also minimize the effects of radiation. Supplements like this, also used in cancer patients on Earth during radiation therapy, can alleviate gastrointestinal side effects of radiation exposure.</p>
<h2>Gravitational changes</h2>
<p>Astronauts have to exercise in space to minimize the muscle loss they’ll face after a long mission. Missions that go as far as Mars will have to make sure <a href="https://www.nasa.gov/mission_pages/station/research/benefits/bone_loss.html">astronauts have supplements</a> such as <a href="https://my.clevelandclinic.org/health/treatments/24753-bisphosphonates">bisphosphonate</a>, which is used to prevent bone breakdown in osteoporosis. These supplements should keep their muscles and bones in good condition over long periods of time spent without the <a href="https://doi.org/10.1038/s41526-021-00158-4">effects of Earth’s gravity</a>. </p>
<p>Microgravity also affects the nervous and circulatory systems. On Earth, your heart pumps blood upward, and specialized valves in your circulatory system keep bodily fluids from pooling at your feet. In the absence of gravity, <a href="https://doi.org/10.3390/life4040621">fluids shift</a> toward the head.</p>
<p>My work and that of others has shown that this results in an expansion of fluid-filled spaces in the middle of the brain. Having extra fluid in the skull and no gravity to “hold the brain down” causes the <a href="https://doi.org/10.1016/j.neubiorev.2020.11.017">brain to sit higher in the skull</a>, compressing the top of the brain against the inside of the skull.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man wearing a white headset and a suit which has many wires coming out of it and a plastic panel connected to a laptop." src="https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=901&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=901&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=901&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1133&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1133&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1133&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">NASA astronaut Scott Kelly, pictured here, is wearing the Chibis lower body negative pressure suit, which may help counteract the negative effects of gravity-caused fluid shifts in the body.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/mission_pages/station/research/news/b4h-3rd/hh-dressing-astronauts-for-return">NASA</a></span>
</figcaption>
</figure>
<p>These fluid shifts may contribute to <a href="https://doi.org/10.1038/s41526-020-0097-9">spaceflight associated neuro-ocular syndrome</a>, a condition experienced by many astronauts that affects the <a href="https://doi.org/10.1136/bjo-2022-322892">structure and function of the eyes</a>. The back of the eye can become flattened, and the nerves that carry visual information from the eye to the brain swell and bend. Astronauts can still see, though visual function may worsen for some. Though it hasn’t been well studied yet, <a href="https://doi.org/10.1038/s41526-020-0097-9">case studies suggest</a> this condition may persist even a few years after returning to Earth. </p>
<p>Scientists may be able to shift the fluids back toward the lower body using <a href="https://www.nasa.gov/mission_pages/station/research/news/b4h-3rd/hh-dressing-astronauts-for-return">specialized “pants</a>” that pull fluids back down toward the lower body like a vacuum. These pants could be used to redistribute the body’s fluids in a way that is more similar to what occurs on Earth.</p>
<h2>Mental health and isolation</h2>
<p>While space travel can damage the body, the isolating nature of space travel can also have <a href="https://www.doi.org/10.36131/cnfioritieditore20210502">profound effects on the mind</a>. </p>
<p>Imagine having to live and work with the same small group of people, without being able to see your family or friends for months on end. To learn to manage extreme environments and maintain communication and leadership dynamics, astronauts first undergo team training on Earth. </p>
<p>They spend weeks in either <a href="https://www.nasa.gov/mission_pages/NEEMO/index.html">NASA’s Extreme Environment Mission Operations</a> at the <a href="https://www.nasa.gov/mission_pages/NEEMO/facilities.html">Aquarius Research Station</a>, <a href="https://theconversation.com/how-nine-days-underwater-helps-scientists-understand-what-life-on-a-moon-base-will-be-like-121079">found underwater</a> off the Florida Keys, or mapping and exploring caves with the European Space Agency’s <a href="https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/CAVES_and_Pangaea/What_is_CAVES">CAVES program</a>. These programs help astronauts build camaraderie with their teammates and learn how to manage stress and loneliness in a hostile, faraway environment.</p>
<p>Researchers are studying how to best monitor and support <a href="https://www.nasa.gov/feature/conquering-the-challenge-of-isolation-in-space-nasa-s-human-research-program-director">behavioral mental health</a> under these extreme and isolating conditions. </p>
<p>While space travel comes with stressors and the potential for loneliness, astronauts describe experiencing an <a href="https://doi.org/10.1037/cns0000086">overview effect</a>: a sense of awe and connectedness with all humankind. This often happens when viewing Earth from the International Space Station. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The Earth, half-obscured by shadow, as seen hanging in darkness, from the Moon." src="https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Earthrise, a famous image taken during an Apollo mission, shows the Earth from space. While seeing the Earth from afar, many astronauts report feeling an awed ‘overview effect.’</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Earthrise#/media/File:NASA-Apollo8-Dec24-Earthrise.jpg">NASA</a></span>
</figcaption>
</figure>
<p>Learning how to support human health and physiology in space also has numerous <a href="https://technology.nasa.gov/">benefits for life on Earth</a>. For example, products that shield astronauts from space radiation and counter its harmful effects on our body can also treat cancer patients receiving radiation treatments. </p>
<p>Understanding how to protect our bones and muscles in microgravity could improve how doctors treat the frailty that often accompanies aging. And space exploration has led to many technological achievements advancing <a href="https://www.nasa.gov/mission_pages/station/research/benefits/water_purification.html">water purification</a> and <a href="https://theconversation.com/landsat-turns-50-how-satellites-revolutionized-the-way-we-see-and-protect-the-natural-world-186986">satellite systems</a>. </p>
<p>Researchers like me who study ways to preserve astronaut health expect our work will benefit people both in space and here at home.</p><img src="https://counter.theconversation.com/content/210761/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rachael Seidler receives funding from the National Aeronautics and Space Administration, the Translational Research Institue for Space Health, the National Science Foundation, the National Institutes of Health, and the Office of Naval Research.</span></em></p>Space can damage everything from your cardiovascular and nervous systems to your mental health – long voyages can feel isolating for many.Rachael Seidler, Professor of Applied Physiology & Kinesiology, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2133942023-09-13T13:57:15Z2023-09-13T13:57:15ZPossible hints of life found on distant planet – how excited should we be?<figure><img src="https://images.theconversation.com/files/547762/original/file-20230912-19-lzosd4.jpeg?ixlib=rb-1.1.0&rect=5%2C0%2C3811%2C2160&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The exoplanet K2-18b might host a water ocean.</span> <span class="attribution"><a class="source" href="https://www.nasa.gov/goddard/2023/webb-discovers-methane-carbon-dioxide-in-atmosphere-of-k2-18b">Credits: Illustration: NASA, CSA, ESA, J. Olmsted (STScI), Science: N. Madhusudhan (Cambridge University)</a></span></figcaption></figure><p>Data from the <a href="https://webb.nasa.gov/">James Webb Space Telescope</a> (JWST) has shown that an exoplanet around a star in the constellation Leo has some of the chemical markers that, on Earth, are associated with living organisms. But these are vague indications. So how likely is it that this exoplanet harbours alien life?</p>
<p>Exoplanets are worlds that orbit stars other than the Sun. The planet in question is named <a href="http://www.exoplanetkyoto.org/exohtml/K2-18.html">K2-18b</a>. It’s so named because it was the first planet found to orbit the red dwarf star K2-18. There is a K2-18c as well – the second planet to be discovered. The star itself is dimmer and cooler than the Sun, meaning that, to get the same level of light as we do on Earth, the planet would need to be much closer to its star than we are. </p>
<p>The system is roughly 124 light years away, which is close in astronomical terms. So what are conditions like on this exoplanet? This is a difficult question to answer. We have telescopes and techniques powerful enough to tell us what the star is like, and how far away the exoplanet is, but we can’t capture direct images of the planet. We can work out a few basics, however. </p>
<p>Working out how much light hits K2-18b is important for assessing the planet’s potential for life. K2-18b orbits closer to its star than Earth does: it’s at roughly 16% of the distance from Earth to the Sun. Another measurement we need is the star’s power output: the total amount of energy it radiates per second. K2-18’s power output is 2.3% that of the Sun. </p>
<p>Using geometry, we can work out that K2-18b receives about 1.22 kilowatts (kW) in solar power per square metre. <a href="https://www.sws.bom.gov.au/Educational/2/1/12">This is similar</a> to the 1.36 kW of incoming light we receive on Earth. Although there’s less energy coming from K2-18, it evens out because the planet is closer. So far, so good. However, the incoming light calculation doesn’t take into account clouds or how reflective the planet’s surface is.</p>
<figure class="align-center ">
<img alt="JWST" src="https://images.theconversation.com/files/548036/original/file-20230913-19-odwob3.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548036/original/file-20230913-19-odwob3.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548036/original/file-20230913-19-odwob3.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548036/original/file-20230913-19-odwob3.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548036/original/file-20230913-19-odwob3.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548036/original/file-20230913-19-odwob3.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548036/original/file-20230913-19-odwob3.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">Artist’s impression of the James Webb Space Telescope (JWST).</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/feature/ames/webb">NASA</a></span>
</figcaption>
</figure>
<p>When we consider life on other planets, a popular term to use is the <a href="https://exoplanets.nasa.gov/search-for-life/habitable-zone/">habitable zone</a>, which means that at an average surface temperature, water will be in a liquid state – as this condition is considered essential for life. In 2019, the Hubble Space Telescope determined that K2-18b showed signs of <a href="https://www.nature.com/articles/s41550-019-0878-9#change-history">water vapour</a>, suggesting that liquid water would be present on the surface. It is currently thought that there are large oceans on the planet.</p>
<p>This caused a ripple of excitement at the time, but without further evidence it was just an interesting result. Now we have reports that JWST has identified carbon dioxide, methane and – possibly – the compound dimethyl sulfide (DMS) <a href="https://www.nasa.gov/goddard/2023/webb-discovers-methane-carbon-dioxide-in-atmosphere-of-k2-18b">in the atmosphere</a>. The tentative detection of DMS is significant because it is only produced on Earth by <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/dimethyl-sulfide">algae</a>. We currently know of no way it can be naturally produced without a life-form.</p>
<h2>Is there life on K2-18b?</h2>
<p>All these indications seem to suggest that K2-18b might be the place to go to find alien life. It is not quite as simple as that, though, as we have no idea how accurate the results are. The method used to determine what is in the atmosphere of an exoplanet involves light from a different source (usually a star or galaxy) passing through the edge of the atmosphere that is then observed by us. Any chemical compounds will <a href="https://webbtelescope.org/contents/media/images/01FEE26XVSM851DHPVCE1KB4S2">absorb light in specific wavelengths</a> which can then be identified. </p>
<p>Imagine it as looking at a light bulb through a glass tumbler. You can see through it perfectly when empty. If you fill it with water, you can still see through pretty well, but there are some optical effects and colouration, which are the equivalent of hydrogen and dust clouds in space. Now imagine you poured in red food dye – this might be the equivalent of the main chemical constituent in a planet’s atmosphere. </p>
<p>But most atmospheres are made up of many chemicals. The equivalent of looking for any one of them would be like pouring 50 – likely many more – coloured food dyes, in different amounts, into your tumbler and trying to identify how much of one particular colour is present. It is an incredibly difficult task with plenty of room for subjective assessment and errors. In addition, the light going through the atmosphere contains a signal of the star’s chemical constituents – further complicating the analysis.</p>
<figure class="align-center ">
<img alt="Atmospheric composition of K2-18 b." src="https://images.theconversation.com/files/547763/original/file-20230912-17-ds12z4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/547763/original/file-20230912-17-ds12z4.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/547763/original/file-20230912-17-ds12z4.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/547763/original/file-20230912-17-ds12z4.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/547763/original/file-20230912-17-ds12z4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/547763/original/file-20230912-17-ds12z4.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/547763/original/file-20230912-17-ds12z4.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The chemical composition of K2-18b’s atmosphere.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/goddard/2023/webb-discovers-methane-carbon-dioxide-in-atmosphere-of-k2-18b">Credits: Illustration: NASA, CSA, ESA, R. Crawford (STScI), J. Olmsted (STScI), Science: N. Madhusudhan (Cambridge University)</a></span>
</figcaption>
</figure>
<p>Only a few years ago there was a surge of interest in <a href="https://www.nytimes.com/2020/09/14/science/venus-life-clouds.html">whether life existed on Venus</a>, as observations had indicated the presence of phosphine gas, which can be produced by microbes. </p>
<p>However, this finding was later successfully refuted by <a href="https://arxiv.org/pdf/2010.09761.pdf">several studies</a>. If there can be confusion about what is in the atmosphere of a planet that’s just next door, in astronomical terms, it’s easy to see why analysing a planet that’s many times further away is a difficult task.</p>
<h2>What can we take from this?</h2>
<p>The chances of life on exoplanet K2-18b are low but not impossible. These results will likely not change anybody’s opinions or beliefs about extraterrestrial life. Instead, they do demonstrate the advancing ability to look into worlds that are not our own and find more information. </p>
<figure class="align-center ">
<img alt="Rho Ophiuchi" src="https://images.theconversation.com/files/548021/original/file-20230913-21-su4cro.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548021/original/file-20230913-21-su4cro.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=562&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548021/original/file-20230913-21-su4cro.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=562&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548021/original/file-20230913-21-su4cro.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=562&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548021/original/file-20230913-21-su4cro.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=706&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548021/original/file-20230913-21-su4cro.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=706&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548021/original/file-20230913-21-su4cro.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=706&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">JWST image of Rho Ophiuchi, the closest star-forming region to Earth.</span>
<span class="attribution"><a class="source" href="https://webbtelescope.org/contents/media/images/2023/128/01H449193V5Q4Q6GFBKXAZ3S03?news=true">NASA, ESA, CSA, STScI, Klaus Pontoppidan (STScI)</a></span>
</figcaption>
</figure>
<p>The power of JWST is not only in producing incredible pictures, but in providing <a href="https://webbtelescope.org/contents/news-releases/2023/news-2023-103.html">more detailed</a> and accurate data on celestial objects themselves. Knowing which exoplanets host water and which do not could provide information on how the Earth formed. </p>
<p>Studying the atmospheres of gas giant exoplanets can inform the study of similar worlds in the Solar System, such as Jupiter and Saturn. And identifying levels of CO2 indicates how an extreme greenhouse effect might affect a planet. This is the real power of studying the composition of planetary atmospheres.</p><img src="https://counter.theconversation.com/content/213394/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ian Whittaker 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 results are intriguing, but analysing the atmospheres of exoplanets is no easy task.Ian Whittaker, Senior Lecturer in Physics, Nottingham Trent UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2083202023-06-27T15:49:23Z2023-06-27T15:49:23ZEuclid space mission is set for launch – here’s how it will test alternative theories of gravity<figure><img src="https://images.theconversation.com/files/533759/original/file-20230623-27-zpv5wg.jpeg?ixlib=rb-1.1.0&rect=0%2C1%2C769%2C429&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">NASA</span></span></figcaption></figure><p>The European Space Agency’s (Esa) <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid_overview">Euclid mission</a> will launch into space on a Falcon9 rocket from SpaceX on July 1, or soon after. Many of us who have worked on it will be in Florida to watch the nail-biting event.</p>
<p>The mission is specifically <a href="https://theconversation.com/the-euclid-spacecraft-will-transform-how-we-view-the-dark-universe-204245">designed to study</a> the dark universe, probing both “<a href="https://theconversation.com/dark-matter-should-we-be-so-sure-it-exists-heres-how-philosophy-can-help-184109">dark matter</a>” and “<a href="https://theconversation.com/the-experiments-trying-to-crack-physics-biggest-question-what-is-dark-energy-52917">dark energy</a>” – unknown substances thought to make up 95% of the energy density of the universe.</p>
<p>But it will also be able to test some strange, <a href="https://theconversation.com/new-theory-of-general-relativity-casts-doubt-on-dark-matter-16446">alternative models</a> of gravity – potentially challenging Albert Einstein’s great <a href="https://theconversation.com/how-einsteins-general-theory-of-relativity-killed-off-common-sense-physics-50042">theory of general relativity</a>.</p>
<p>Scientists have known about the existence of dark matter for nearly a century now. It was proposed after astronomers noted that galaxies in clusters had mysteriously high speeds. Such speeds should cause the clusters to evaporate unless there was some extra mass holding them together. As this matter wasn’t shining in the same way as the visible galaxies, it was dubbed dark matter. </p>
<p>Gravitational lensing is <a href="https://theconversation.com/method-to-weigh-galaxy-clusters-could-help-us-understand-mysterious-dark-matter-structures-85023">a new tool</a> to see this dark material. This effect relies on our understanding of general relativity. As light travels to us from distant galaxies, its path is bent by large clumps of matter (dark or bright) in the foreground – changing their appearance (and location). </p>
<p>This change is easily seen near the cores of massive clusters (see image below) – with galaxies stretched into arcs, appearing to be long, thin and curved. We can use this warping to determine the amount of matter in the foreground cluster. And that confirms again that much of the mass in these clusters is indeed dark.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Gravitational lensing in the galaxy cluster Abell 1689." src="https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=623&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=623&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=623&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=783&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=783&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533742/original/file-20230623-25-xfx4d6.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=783&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Gravitational lensing in the galaxy cluster Abell 1689.</span>
<span class="attribution"><span class="source">NASA/CXC/MIT/E.-H Peng et al; Optical: NASA/STScI</span></span>
</figcaption>
</figure>
<p>But what <a href="https://theconversation.com/from-machos-to-wimps-meet-the-top-five-candidates-for-dark-matter-51516">could it be made of</a>? Many physicists believe it is an unknown elementary particle. A popular candidate, which is yet to be detected, is axions, which were originally introduced to explain why certain fundamental symmetries of nature appear to be broken.</p>
<p>However, there are other possibilities. Rather than postulating the need for dark matter, one can probe gravity. The strength of gravity may become weaker than predicted on the scale of galaxies and beyond. On these scales, there are some alternative models of gravity that <a href="https://theconversation.com/dark-matter-our-review-suggests-its-time-to-ditch-it-in-favour-of-a-new-theory-of-gravity-186344">can explain galaxy rotation curves</a> without assuming there’s any dark matter. The challenge for any of these alternatives is to do so consistently on all scales. </p>
<p>While there are several Earth-based searches for dark matter particles, they have so far not found significant evidence. Therefore, astronomical observations of galaxy clusters remain our best option for testing the various theories that can explain dark matter. This is where Euclid will excel due to its outstanding resolution, providing a sharpness similar to the Hubble space telescope (see image) across a third of the sky. By comparison, Hubble has observed only 5% of the whole sky. </p>
<p>The number of images we will obtain of clusters will increase a hundred-fold with Euclid, allowing us to study in detail the distribution of dark matter within such clusters to high precision. How the dark matter is distributed may be key to its origin and mass, ruling out a range of possible candidate particles and gravity theories along the way. </p>
<h2>Dark energy and gravity</h2>
<p>Dark matter is potentially easy to understand compared to <a href="https://theconversation.com/the-experiments-trying-to-crack-physics-biggest-question-what-is-dark-energy-52917">dark energy</a>, which was proposed to explain the discovery that the expansion of the universe is accelerating – at odds with the prediction from Einstein’s theory of gravity. This strange substance is vexing to physicists and cosmologists, with the simplest idea being that dark energy is just <a href="https://theconversation.com/what-is-nothing-martin-rees-qanda-101498">the energy of empty space</a> (“vacuum energy”). </p>
<p>Essentially, as we gain more space in an expanding universe, we gain more vacuum energy, which then drives the observed acceleration. </p>
<p>This simple explanation is reasonable except for the uncomfortable truth that the observed density of dark energy is many orders of magnitude lower than predicted by quantum theory, which rules the universe on the smallest of scales. In short, this simple explanation asks more questions than it answers.</p>
<p>As with dark matter, an alternative explanation for dark energy is that it isn’t really a substance or form of energy at all, but again a sign that gravity is behaving differently on the largest scales. </p>
<p>This has led to a flurry of new ideas that extend our theory of gravity beyond general relativity. For example, could gravity exist in <a href="https://arxiv.org/abs/hep-th/0005016">more than the four dimensions</a> (three spatial dimensions plus time) that the rest of the universe experiences? Are there <a href="https://arxiv.org/abs/1901.07183">new fundamental fields</a> that we don’t know about yet, which interact with gravity? </p>
<p>Or perhaps Einstein’s theory is valid for the weak gravitational fields we experience on Earth, but becomes radically <a href="https://iopscience.iop.org/article/10.1088/0264-9381/32/24/243001">different in extremely strong gravitational fields</a>, like those near the event horizons of black holes.</p>
<p>The challenge for all these alternative gravity models is to work together, for both dark matter and dark energy. Ideally, they should work on all scales and masses, as a single theory. Physicists believe strongly in Occam’s razor – that the best theories have the least number of assumptions.</p>
<p>Euclid will help us test these exotic gravity models by mapping the positions of millions of galaxies over vast regions of the universe. This allows us to trace the “<a href="https://theconversation.com/scientists-start-mapping-the-hidden-web-that-scaffolds-the-universe-124616">cosmic web</a>”, a sponge-like structure of filaments and voids in space. These seem to be laid down first in dark matter and then sprinkled with galaxies. </p>
<p>This cosmic web is formed by billions of years of gravitational collapse, meaning its structure and statistics are sensitive to the laws of gravity at work on cosmological scales. By measuring its properties, we can determine whether a new theory of gravity would fit the data better than Einstein’s theory. </p>
<p>As we return to Earth, there is much excitement in the astrophysics community about what Euclid will do. This is the first time we’ve had a <a href="https://theconversation.com/the-euclid-spacecraft-will-transform-how-we-view-the-dark-universe-204245">satellite dedicated to</a> mapping dark matter and dark energy. </p>
<p>The Euclid data will last a lifetime and generations of cosmologists will spend their careers studying it. As we watch Euclid launch into the Florida sky, we will be one step closer to answering some of the most fundamental questions in science.</p><img src="https://counter.theconversation.com/content/208320/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robert Nichol has received funding in the past for his work on Euclid and remains a member of the Euclid Consortium Board.</span></em></p><p class="fine-print"><em><span>Tessa Baker receives funding from the Royal Society and the European Research Council. </span></em></p>The Euclid mission is preparing to launch on July 1.Robert Nichol, Pro Vice-Chancellor and Executive Dean, University of SurreyTessa Baker, Royal Society University Research Fellow, Reader in Cosmology, Queen Mary University of LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2032042023-04-12T17:18:09Z2023-04-12T17:18:09ZScientists launch JUICE mission to explore Jupiter’s icy moons<figure><img src="https://images.theconversation.com/files/520598/original/file-20230412-24-axm9rh.jpeg?ixlib=rb-1.1.0&rect=0%2C20%2C1920%2C1057&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Jupiter has more than 80 moons, the largest of which were discovered by Galileo. Many will be studied in depth by the scientific instruments of ESA's JUICE mission.</span> <span class="attribution"><span class="source">ESA, NASA, JPL, ATG, DLR, University of Arizona, University of Leicester</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Could we discover conditions necessary for life outside the Earth in the solar system?</p>
<p>This is one of the mysteries that the space mission <a href="https://www.esa.int/Science_Exploration/Space_Science/Juice_factsheet">JUICE</a> (for <em>JUpiter ICy moons Explorer</em>) will look to elucidate. Initially set to be launched from Kourou, French Guiana, in the early afternoon of Thursday 13 April 2023, the spacecraft will now be <a href="https://www.rfi.fr/en/international/20230413-bad-weather-forces-postponement-of-jupiter-space-mission-juice">leaving on Friday</a> due to bad weather.</p>
<p>To propel this mission to a planet located more than 600 million kilometres away, the <a href="https://esamultimedia.esa.int/docs/corporate/This_is_ESA_FR_LR.pdf">European Space Agency</a> (ESA) has brought together no fewer than 13 European countries, as well as the United States, Japan, and Israel. Through this mission, the agency has also managed the feat of placing JUICE on the launch pad only 11 years after the project was greenlit. While the Covid pandemic slowed down the process, the delay was only nine months. France’s team, of which I am a part, also <a href="https://www.cnrs.fr/fr/cnrsinfo/cnrs-cnes-lespace-main-dans-la-main">helped develop</a> six of JUICE’s ten state-of-the-art scientific instruments. The probe is expected to arrive in the Jovian system in 2031.</p>
<h2>Stretching science’s boundaries</h2>
<p>Jupiter is both the largest planet in our solar system and the one with the most moons. To date, estimates of their number hover between <a href="https://fr.wikipedia.org/wiki/Satellites_naturels_de_Jupiter">82 and 95</a>, most of which have been discovered in the last two decades.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Swirling clouds on the surface of Jupiter" src="https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=270&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=270&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=270&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=340&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=340&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519068/original/file-20230403-16-777o7x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=340&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Jupiter’s turbulent atmosphere.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/image-feature/jpl/churning-texture-in-jupiter-s-atmosphere">NASA/JPL-Caltech/SwRI/MSSS, Kevin M. Gill</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>JUICE is the first mission to receive more than 1 billion euros of funding as part of the ESA’s <a href="https://www.esa.int/Science_Exploration/Space_Science/ESA_s_Cosmic_Vision">Cosmic Vision</a> programme. It seeks to address four main questions:</p>
<ul>
<li><p>How do planets come to form and life to emerge?</p></li>
<li><p>How does the Solar System work?</p></li>
<li><p>What are the fundamental laws of physics in the universe?</p></li>
<li><p>How did the present universe come into being and what is it made of?</p></li>
</ul>
<p>JUICE was chosen ahead of other proposed missions because it was designed to address the first and last of these questions.</p>
<p>The <a href="https://theconversation.com/how-the-hubble-space-telescope-opened-our-eyes-to-the-first-galaxies-of-the-universe-133877">Hubble Space Telescope</a> and NASA’s space probes <a href="https://theconversation.com/what-the-voyager-space-probes-can-teach-humanity-about-immortality-and-legacy-as-they-sail-through-space-for-trillions-of-years-177513">Voyager</a>, <a href="https://www.jpl.nasa.gov/missions/galileo">Galileo</a>, <a href="https://www.nasa.gov/mission_pages/juno/main/index.html">Juno</a> have already picked up some clues either by direct observation or deduction.</p>
<h2>“Ocean moons” containing more water than the Earth</h2>
<p>NASA’s Galileo was the first to discover <a href="https://history.nasa.gov/sp4231.pdf">water on the moons</a> in 1995. Data captured by the space probe revealed gigantic liquid oceans not only under the crusts of its three icy moons, Callisto, Europa and Ganymede, but also on its <a href="https://theconversation.com/dou-viennent-les-aurores-boreales-et-pourquoi-sont-elles-si-differentes-sur-jupiter-186776">volcanic</a> moon, Io.</p>
<p>In 2014, the Hubble Space Telescope discovered geysers in Europa. Their bases appeared to be caked with <a href="https://planet-terre.ens-lyon.fr/planetterre/objets/Images/vie-Europe-Jupiter-2014/vie-Europe-satellite-Jupiter.pdf">salts</a>, including carbonates. It is therefore likely Europa could meet the <a href="https://planet-terre.ens-lyon.fr/ressource/habitabilite-vie-systeme-solaire.xml">four criteria</a> for habitability:</p>
<ul>
<li><p>The famous quartet of <a href="https://en.wikipedia.org/wiki/CHON">carbon, hydrogen, oxygen, nitrogen</a> (CHON), symbols of the main chemical elements that constitute living beings.</p></li>
<li><p>Liquid water that acts as a solvent.</p></li>
<li><p>Energy to enable the development of life.</p></li>
<li><p>A stable environment (orbits, rotation, average temperatures…)</p></li>
</ul>
<p>The Galilean moons further enjoy the gravitational energy of Jupiter, creating significant tidal effects and allowing the last two conditions above to be met.</p>
<h2>Why Ganymede is the main objective</h2>
<p>Ganymede is set to studied in much more depth by JUICE than Callisto and Europa. This is not only because it is the largest moon in the Solar System, but also an ocean moon with its own magnetic field. Similarly to the Earth’s magnetosphere, Ganymede’s has the potential to protect life by diverting the flow of cosmic rays and radiative particles from Jupiter’s <a href="https://fr.wikipedia.org/wiki/Ceinture_de_radiations">radiation belts</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Ganymede’s northern lights" src="https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=503&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=503&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=503&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=631&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=631&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519078/original/file-20230403-22-1np1wb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=631&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Ganymede’s northern lights belts appear bathed in Jupiter’s magnetic field. When Jupiter’s magnetic field changes, the auroras sway – and this swaying motion indicates that a huge amount of salt water would be present under the crust of Ganymede, affecting its own magnetic field.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/sites/default/files/thumbnails/image/15-33i2.png">NASA/ESA</a></span>
</figcaption>
</figure>
<h2>JUICE, a probe of the extreme</h2>
<p>JUICE’s itinerary to the Jovian system will not be following a straight line. Instead, the spacecraft will fly by four different planets and moons that will alter and speed its trajectory, enabling it to save fuel as well – a trick also known as a <a href="https://en.wikipedia.org/wiki/Gravity_assist">gravity assist manoeuvre</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="timeline" src="https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=188&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=188&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=188&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=236&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=236&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519081/original/file-20230403-28-amat5c.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=236&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">JUICE’s long journey to the Jovian system.</span>
<span class="attribution"><a class="source" href="https://esamultimedia.esa.int/docs/science/Juice-LaunchKit_FR.pdf">ESA</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Along the way, JUICE will have to contend with the Solar System’s highest radiation levels. This means that its electronic modules have to be housed in lead-shielded cavities and <a href="https://fr.wikipedia.org/wiki/Durcissement_(%C3%A9electronics)">components have to be “hardened”</a> to help them resist the harsh environment.</p>
<p>JUICE will also have to cope with extreme temperatures, ranging from +250°C as it flies by Venus to -230°C in the Jovian system. To maintain a stable internal temperature, the spacecraft has been coated with a <a href="https://en.wikipedia.org/wiki/Multi-layer_insulation">multilayer thermal insulation</a> made out of grey silicon aluminium alloy, earning the probe the nickname “silver beauty”.</p>
<h2>An energy problem</h2>
<p>Around Jupiter, which is five times further from the Sun than Earth, the satellite will receive 25 times less solar energy than it would around Earth. The spacecraft does not carry a <a href="https://fr.wikipedia.org/wiki/G%C3%A9n%C3%A9rateur_thermo%C3%A9lectrique_%C3%A0_radioisotope">radioactive battery</a> because Europe is not yet able to produce them industrially, unlike the <a href="https://nuke.fas.org/space/bennett0706.pdf">United States</a>, Russia and China.</p>
<p>To enable the equipment and instruments to function with 1000W (the power of a small hairdryer), the craft will rely on huge solar panels – their surface area totals 85m2 – that have been tested to withstand the radiation and temperature variations.</p>
<figure class="align-center ">
<img alt="photo of the JUICE panels" src="https://images.theconversation.com/files/519083/original/file-20230403-20-ocb3ob.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519083/original/file-20230403-20-ocb3ob.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519083/original/file-20230403-20-ocb3ob.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519083/original/file-20230403-20-ocb3ob.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519083/original/file-20230403-20-ocb3ob.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519083/original/file-20230403-20-ocb3ob.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519083/original/file-20230403-20-ocb3ob.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Test deployment of JUICE’s solar panels, whose two wings comprise five panels of 2.5 times 3.5 metres each, arranged in a cross pattern.</span>
<span class="attribution"><a class="source" href="https://www.esa.int/ESA_Multimedia/Images/2022/06/Juice_solar_array_deployment_test2"> Airbus</a>, <span class="license">Fourni par l'auteur</span></span>
</figcaption>
</figure>
<p>Built by 80 European companies under the direction of EADS Toulouse, the JUICE probe has a wingspan of 28 metres (the length of a basketball court), a 2.5-metre long communications antenna (needed because of Jupiter’s distance from the Earth). It weighs nearly 6 tonnes at liftoff (most of which is propellant that will be consumed in manoeuvring the probe) and carries ten instruments (in all, less than 280 kg).</p>
<h2>Ten scientific instruments on board</h2>
<p>Of these instruments, France – with assistance from Italy – chiefly engineered the <a href="https://www.insu.cnrs.fr/fr/cnrsinfo/majis-un-spectro-imageur-pour-explorer-jupiter-et-ses-lunes">Moons and Jupiter Imaging Spectrometer</a> (MAJIS). It is the instrument that will allow the spacecraft to determine the physico-chemical compositions of the moons’ surfaces as it flies over them and thus detect the CHON associated with potential habitability.</p>
<p>MAJIS will also study their ice sheets and liquid water. This will enable us to identify landing sites for future <em>in situ</em> exploration, and evaluate the structure and dynamics of Jupiter’s atmosphere.</p>
<p>With an accuracy 10,000 times higher than the equivalent instrument on Galileo, the spatial resolution of MAJIS ranges between <a href="https://lejournal.cnrs.fr/articles/objectif-jupiter">100 metres and several kilometres</a> depending on the probe’s altitude at the time.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/zkKt9pyseQg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">JUICE mission: Ask about the moons! (CNES).</span></figcaption>
</figure>
<p>Finally, it should be noted that JUICE’s plans may be revised based on the latest results from NASA’s Juno mission. Juno is still orbiting Jupiter and has been flying over its poles since 2016. Juno’s nominal mission has been extended to fly past each of Jupiter’s Galilean moons, starting with Ganymede in June 2021, and Europa in early 2023. These observations and subsequent data analysis will allow JUICE scientists to better target the observations they make – 12 years after Juno and 30 years after Galileo.</p>
<hr>
<p><em>The French laboratories involved in the development of JUICE are <a href="https://www.ias.u-psud.fr/fr">IAS</a>, <a href="https://astrophy.u-bordeaux.fr/">LAB</a>, <a href="https://www3.latmos.ipsl.fr/index.php/fr/">LATMOS</a>, <a href="https://ipag.osug.fr/">IPAG</a>, <a href="https://www.irap.omp.eu/">IRAP</a>, <a href="https://lerma.obspm.fr/">LERMA</a>, <a href="https://lesia.obspm.fr/">LESIA</a>, <a href="https://www.lpc2e.cnrs.fr/">LPC2E</a> and <a href="https://www.lpp.polytechnique.fr/">LPP</a>.</em></p><img src="https://counter.theconversation.com/content/203204/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Carole Larigauderie is a member of WIA (Women In Aerospace) and a sponsor within "Elles bougent".</span></em></p>One of Jupiter’s moons, Ganymede, could contain more water than the Earth.Carole Larigauderie, Sous-directrice adjointe des Projets en Sciences de l’Univers et Cheffe de Projet des contributions françaises à JUICE, Centre national d’études spatiales (CNES)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2032072023-04-10T12:10:25Z2023-04-10T12:10:25ZJupiter’s moons hide giant subsurface oceans – two missions are sending spacecraft to see if these moons could support life<figure><img src="https://images.theconversation.com/files/519960/original/file-20230407-28-6r7tcb.jpg?ixlib=rb-1.1.0&rect=51%2C27%2C2224%2C1425&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The surface of Europa – one of Jupiter's moons – is a thick layer of solid ice.</span> <span class="attribution"><a class="source" href="https://solarsystem.nasa.gov/resources/204/europas-stunning-surface/?category=moons/jupiter-moons_europa">NASA/JPL-Caltech/SETI Institute</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>On April 13, 2023, the European Space Agency launched a rocket carrying a spacecraft destined for Jupiter. The <a href="https://www.esa.int/Science_Exploration/Space_Science/Juice">Jupiter Icy Moons Explorer</a> – or JUICE – will spend at least three years on Jupiter’s moons after it arrives in 2031. In October 2024, NASA is also planning to launch a robotic spacecraft named <a href="https://europa.nasa.gov/">Europa Clipper</a> to the Jovian moons, highlighting an increased interest in these distant, but fascinating, places in the solar system.</p>
<p><a href="https://www.michaelmsori.com/">I’m a planetary scientist</a> who studies the <a href="https://scholar.google.com/citations?user=NLWIrYoAAAAJ&hl=en&oi=ao">structure and evolution of solid planets and moons</a> in the solar system. </p>
<p>There are many reasons my colleagues and I are looking forward to getting the data that JUICE and Europa Clipper will hopefully be sending back to Earth in the 2030s. But perhaps the most exciting information will have to do with water. Three of Jupiter’s moons – Europa, Ganymede and Callisto – are home to large, underground oceans of liquid water that could support life.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four moons next to a large red spot on the surface of Jupiter." src="https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=857&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=857&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=857&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1077&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1077&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519961/original/file-20230407-16-27nqat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1077&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This composite image shows, from top to bottom, Io, Europa, Ganymede and Callisto next to Jupiter.</span>
<span class="attribution"><a class="source" href="https://solarsystem.nasa.gov/resources/2662/family-portrait-of-the-jovian-system/?category=moons/jupiter-moons_europa">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Meet Io, Europa, Ganymede and Callisto</h2>
<p>Jupiter has dozens of moons. Four of them in particular are of interest to planetary scientists.</p>
<p>Io, Europa, Ganymede and Callisto are, like Earth’s Moon, relatively large, spherical complex worlds. Two previous NASA missions have sent spacecraft to orbit the Jupiter system and collected data on these moons. The <a href="https://solarsystem.nasa.gov/missions/galileo/overview/">Galileo mission</a> orbited Jupiter from 1995 to 2003 and led to geological discoveries on all four large moons. The <a href="https://www.nasa.gov/mission_pages/juno/main/index.html">Juno mission</a> is still orbiting Jupiter today and has provided scientists with an unprecedented view into Jupiter’s composition, structure and space environment. </p>
<p>These missions and other observations revealed that Io, the closest of the four to its host planet, is <a href="https://doi.org/10.1146/annurev.earth.31.100901.145428">abuzz with</a> <a href="https://doi.org/10.1038/nature22339">geological activity</a>, including lava lakes, volcanic eruptions and tectonically formed mountains. But it is not home to large amounts of water.</p>
<p>Europa, Ganymede and Callisto, in contrast, have icy landscapes. Europa’s surface is a frozen wonderland with a young but complex history, <a href="https://doi.org/10.1038/ngeo2245">possibly including icy analogs</a> of plate tectonics and volcanoes. Ganymede, the largest moon in the entire solar system, is bigger than Mercury and has its own magnetic field <a href="https://doi.org/10.1038/384544a0">generated internally from a liquid metal core</a>. Callisto appears somewhat inert compared to the others, but serves as a valuable time capsule of an ancient past that is no longer accessible on the youthful surfaces of Europa and Io.</p>
<p>Most exciting of all: Europa, Ganymede and Callisto all almost certainly possess <a href="https://www.nasa.gov/specials/ocean-worlds/">underground oceans of liquid water</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing a cutaway of Europa." src="https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=570&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=570&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=570&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=716&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=716&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519962/original/file-20230407-16-ddggzn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=716&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Warmth from Europa’s interior and tidal energy from Jupiter likely maintain a massive liquid ocean beneath the moon’s icy surface.</span>
<span class="attribution"><a class="source" href="https://photojournal.jpl.nasa.gov/jpeg/PIA24477.jpg">NASA/JPL-Caltech/Michael Carroll</a></span>
</figcaption>
</figure>
<h2>Ocean worlds</h2>
<p>Europa, Ganymede and Callisto have chilly surfaces that are <a href="https://europa.nasa.gov/resources/114/daytime-temperatures-on-europa/">hundreds of degrees below zero</a>. At these temperatures, ice behaves like solid rock. </p>
<p>But <a href="https://theconversation.com/how-has-the-inside-of-the-earth-stayed-as-hot-as-the-suns-surface-for-billions-of-years-193277">just like Earth</a>, the deeper underground you go on these moons, the hotter it gets. Go down far enough and you eventually reach the temperature where ice melts into water. Exactly how far down this transition occurs on each of the moons is a <a href="https://doi.org/10.1016/j.icarus.2005.03.013">subject of debate</a> that scientists hope to resolve with JUICE and Europa Clipper. While the exact depths are still uncertain, scientists are confident that these oceans exist. </p>
<p>The best evidence of these oceans comes from Jupiter’s magnetic field. Saltwater is electrically conductive. So as these moons travel through Jupiter’s magnetic field, they <a href="https://doi.org/10.1126/science.289.5483.1340">generate a secondary, smaller magnetic field</a> that signals to researchers the presence of an underground ocean. Using this technique, planetary scientists have been able to show that the three <a href="https://doi.org/10.1038/27394">moons contain underground oceans</a>. And these oceans are not small – Europa’s ocean alone might have more than <a href="https://solarsystem.nasa.gov/moons/jupiter-moons/europa/overview/">double the water</a> of all of Earth’s oceans combined.</p>
<p>An obvious and tantalizing next question is whether these oceans can support extraterrestrial life. Liquid water is an important piece of what makes for a habitable world, but far from the only requirement for life. Life also needs <a href="https://astrobiology.nasa.gov/education/primer/">energy and certain chemical compounds</a> in addition to water to flourish. Because these oceans are hidden beneath miles of solid ice, <a href="https://doi.org/10.1126/science.1060081">sunlight and photosynthesis are out</a>. But it’s possible other sources could provide the needed ingredients.</p>
<p>On Europa, for example, the liquid water ocean <a href="https://solarsystem.nasa.gov/moons/jupiter-moons/europa/overview/">overlays a rocky interior</a>. That rocky seafloor could provide energy and chemicals through underwater volcanoes that could make Europa’s ocean habitable. But it is also possible that Europa’s ocean is a sterile, inhospitable place – scientists need more data to answer these questions. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Artist's impression of the JUICE spacecraft approaching Jupiter and the jovian moons." src="https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=339&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=339&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=339&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=426&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=426&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519967/original/file-20230407-16-sd1vga.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=426&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Jupiter Icy Moons Explorer spacecraft will travel for eight years before reaching Jupiter.</span>
<span class="attribution"><a class="source" href="https://sci.esa.int/web/juice/-/59334-exploring-jupiter">ESA/ATG medialab/NASA/JPL/University of Arizona/J. Nichols</a></span>
</figcaption>
</figure>
<h2>Upcoming missions from ESA and NASA</h2>
<p>JUICE and Europa Clipper are set up to give scientists game-changing information about the potential habitability of Jupiter’s moons. While both missions will gather data on multiple moons, JUICE will spend time orbiting and focusing on Ganymede, and Europa Clipper will make dozens of close flybys of Europa.</p>
<p>Both of the spacecraft will carry a suite of scientific instruments built specifically to investigate the oceans. Onboard radar will allow JUICE and Europa Clipper <a href="https://rslab.disi.unitn.it/rime/">to probe into the moons’</a> <a href="https://europa.nasa.gov/spacecraft/instruments/reason/">outer layers of solid ice</a>. Radar could reveal any small pockets of liquid water in the ice, or, in the case of Europa, which has a thinner outer ice layer than Ganymede and Callisto, <a href="https://doi.org/10.1016/j.icarus.2016.08.014">hopefully detect the larger ocean</a>. </p>
<p><a href="https://europa.nasa.gov/spacecraft/instruments/ecm/">Magnetometers will also be</a> <a href="https://www.esa.int/Science_Exploration/Space_Science/Juice_factsheet">on both missions</a>. These tools will give scientists the opportunity to study the secondary magnetic fields produced by the interaction of conductive oceans with Jupiter’s field in great detail and will hopefully give researchers clues to salinity and volumes of the oceans. </p>
<p>Scientists will also observe small variations in the moons’ gravitational pulls by tracking subtle movements in both spacecrafts’ orbits, which could help determine if Europa’s seafloor has volcanoes that <a href="https://doi.org/10.1016/j.icarus.2019.02.025">provide the needed energy and chemistry</a> for the ocean to support life.</p>
<p>Finally, both craft will carry a host of cameras and light sensors that will provide unprecedented images of the geology and composition of the moons’ icy surfaces. </p>
<p>Maybe one day, a spacecraft will be able to drill through the miles of solid ice on Europa, Ganymede or Callisto and explore oceans directly. Until then, observations from spacecraft like JUICE and Europa Clipper are scientists’ best bet for learning about these ocean worlds.</p>
<p>When Galileo discovered these moons in 1609, they were the first objects known to directly orbit another planet. Their discovery was the final nail in the coffin of the theory that Earth – and humanity – resides at the center of the universe. Maybe these worlds have another humbling surprise in store.</p><img src="https://counter.theconversation.com/content/203207/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Sori receives funding from NASA. </span></em></p>The Jupiter Icy Moons Explorer and Europa Clipper missions will arrive at Jupiter in the 2030s and provide researchers with unprecedented access to the icy moons orbiting the gas giant.Mike Sori, Assistant Professor of Planetary Science, Purdue UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/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/1993572023-02-06T17:01:03Z2023-02-06T17:01:03ZEarthquake in Turkey and Syria: how satellites can help rescue efforts<p>In disasters like the <a href="https://www.lemonde.fr/international/article/2023/02/06/le-sud-de-la-turquie-frappe-par-un-seisme-de-magnitude-7-8_6160659_3210.html">7.8 magnitude earthquake</a> and <a href="https://earthquake.usgs.gov/earthquakes/map/?currentFeatureId=us6000jlqa&extent=30.41078,25.37842&extent=42.90816,49.98779">7.5-magnitude aftershock</a> that struck Syria and Turkey on February 6, 2023, international cooperation on satellite imaging plays a crucial role in the rescue and recovery efforts.</p>
<p>Such data enables humanitarian aid to better deliver water and food by mapping the condition of roads, bridges, buildings, and – most crucially – identifying populations trying to escape potential aftershocks by gathering in stadiums or other open spaces.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="satellite photo and location of multiple earthquakes that have struck Turkey and Syria" src="https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=301&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=301&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=301&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=378&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=378&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508350/original/file-20230206-31-phy2vy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=378&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Earthquakes that have occurred since Sunday afternoon, February 5, in the region. In blue, the 7.8 magnitude earthquake. In orange, the numerous aftershocks: the size of the disc indicates the magnitude.</span>
<span class="attribution"><a class="source" href="https://earthquake.usgs.gov/earthquakes/map/?currentFeatureId=us6000jllz&extent=23.68477,12.74414&extent=48.54571,61.96289&baseLayer=satellite">USGS</a></span>
</figcaption>
</figure>
<p>To quickly turn the eyes of satellites toward the affected areas, the Turkish Disaster and Emergency Management Authority (<a href="https://en.afad.gov.tr/">AFAD</a>) requested the activation of the international charter on <a href="https://disasterscharter.org/web/guest/home">“Space and Major Disasters”</a> at 7:04 a.m. local time. The United Nations did so for Syria at 11:29 local time.</p>
<p>In the meantime, 11 space agencies got ready to operate the most appropriate optical and radar satellites. For France, these are the optical satellites <a href="https://spot.cnes.fr/fr">Spot</a>, <a href="https://pleiades.cnes.fr/en/PLEIADES/index.htm">Pléaides</a> and <a href="https://earth.esa.int/eogateway/missions/pleiades-neo">Pléiades Neo</a> (medium, high and very high resolution), which will provide the first images as they pass over the area. Radar satellites will complement the optical information, as they also operate at night and through clouds, and can image landslides and even very small changes in altitude.</p>
<p>Every year, millions of people around the world are affected by disasters, whether natural (cyclone, tornado, typhoon, earthquake, landslide, volcanic eruption, tsunami, flood, forest fire, etc.) or man-made (oil pollution, industrial explosions, and more). Unfortunately, the intensity and frequency of these disasters are increasing with climate change, creating more and more victims, damaged homes, and devastated landscapes.</p>
<h2>Anatomy of a disaster</h2>
<p>The international charter on <a href="https://disasterscharter.org/web/guest/home">“Space and Major Disasters”</a> defines a disaster as a large-scale, sudden, unique and uncontrolled event, resulting in loss of life or damage to property and the environment, and requiring urgent action to acquire and provide data.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/466030/original/file-20220530-20-a1wa4d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466030/original/file-20220530-20-a1wa4d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466030/original/file-20220530-20-a1wa4d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466030/original/file-20220530-20-a1wa4d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466030/original/file-20220530-20-a1wa4d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466030/original/file-20220530-20-a1wa4d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466030/original/file-20220530-20-a1wa4d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Landslide in Munnar, India. Access to affected areas is often difficult.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/rakesh/1933161414/">Rakesh Pai/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>The charter was created by the National Space Research Centre and the European Space Agency in 1999, soon joined by the Canadian Space Agency. Today, <a href="https://disasterscharter.org/web/guest/home">17 member space agencies</a> have joined forces to provide free satellite imagery as quickly as possible over the disaster area. Since 2000, the charter has been activated 797 times in more than 154 countries. It has since been complemented by similar initiatives from Europe (<a href="https://emergency.copernicus.eu/">Copernicus Emergency</a>) and Asia (<a href="https://sentinel-asia.org/">Sentinel Asia</a>).</p>
<p>Almost three quarters of the activations of the charter are due to weather phenomena: storms, hurricanes and especially floods, which alone account for half of the activations. In these sometimes unforeseen crisis situations, when the ground is damaged or flooded and roads are impassable, land-based resources are not always able to analyse the extent of the disaster and organise relief and humanitarian aid in the best possible way. By capturing the situation from space, with very high resolution, satellites provide crucial information quickly.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/466035/original/file-20220530-20-mecx69.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466035/original/file-20220530-20-mecx69.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=289&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466035/original/file-20220530-20-mecx69.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=289&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466035/original/file-20220530-20-mecx69.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=289&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466035/original/file-20220530-20-mecx69.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=363&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466035/original/file-20220530-20-mecx69.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=363&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466035/original/file-20220530-20-mecx69.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=363&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Hurricane Harvey caused flooding in Texas in 2018, displacing 30,000 people, and requiring the rescue of 17,000.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/sentinelhub/46200452394/in/album-72157704784948961/">Sentinel Hub/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>In some cases, the charter cannot be activated. This can be because the subject matter is outside the scope of the charter (wars and armed conflicts) or because space imagery is sometimes of little interest (in the case of heat waves and epidemics), or because the phenomenon evolves slowly and over a long time span (droughts).</p>
<h2>Satellite data in response to crises around the world</h2>
<p>As soon as a disaster occurs, satellites are programmed to quickly acquire images over the affected areas. More than 60 satellites, optical or radar, can be mobilised at any given time.</p>
<p>Depending on the type of disaster, different satellites will be mobilised, based on pre-established crisis plans – among them: <a href="https://en.wikipedia.org/wiki/TanDEM-X">TerraSAR-X/Tandem-X</a>, <a href="https://en.wikipedia.org/wiki/QuickBird">QuickBird-2</a>, <a href="https://www.asc-csa.gc.ca/fra/satellites/radarsat/default.asp">Radarsat</a>, <a href="https://en.wikipedia.org/wiki/Programme_Landsat">Landsat-7/8</a>, <a href="https://en.wikipedia.org/wiki/SPOT_(satellite)">SPOT</a>, <a href="https://en.wikipedia.org/wiki/Pl%C3%A9iades_(satellite)">Pleiades</a>, <a href="https://en.wikipedia.org/wiki/Sentinel-2">Sentinel-2</a> among others.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/466033/original/file-20220530-16-b4snga.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466033/original/file-20220530-16-b4snga.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=289&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466033/original/file-20220530-16-b4snga.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=289&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466033/original/file-20220530-16-b4snga.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=289&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466033/original/file-20220530-16-b4snga.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=363&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466033/original/file-20220530-16-b4snga.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=363&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466033/original/file-20220530-16-b4snga.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=363&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Russian forest fires in the Irkutsk region in 2017, caused by lightning.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/sentinelhub/46200453044/in/photostream/">Sentinel Hub/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Optical images are similar to photos seen from space, but <a href="https://theconversation.com/sismo-citoyens-et-chercheurs-du-monde-entier-sallient-pour-comprendre-le-recent-seisme-dha-ti-166787">radar images</a> can be more difficult to interpret by non-experts. So following the disaster, satellite information is reworked to make it easier to understand. For example, the images are transformed into impact or change maps for rescue workers, flood alert maps for the public, and mapping of burnt or flooded areas with damage estimates for decision-makers.</p>
<p>Collaborative work between field users and satellite operators is essential. Progress has been made thanks to innovations in Earth observation technologies (notably the performance of optical resolutions – from 50 to 20 metres and now 30 centimetres) and 3D data processing software, but also thanks to the development of digital tools that can couple satellite and in situ data. The needs of the field have also contributed to the evolution of the charter’s intervention processes in terms of delivery time and quality of the products delivered.</p>
<h2>Reconstruction after disasters</h2>
<p>Emergency management is of course essential, but it is equally vital for all affected countries to consider reconstruction and the future. Indeed, the <a href="https://centredecrise.be/fr/que-font-les-autorites/le-cycle-du-risque">“risk cycle”</a> posits that reconstruction, resilience and risk prevention all play an important role in the return to normality. While disasters cannot be predicted, they can be better prepared for, especially in countries where they are recurrent. For example, residents could benefit from earthquake-resistant construction, the creation of safe gathering places or relocating to living areas to safe locations. Learning survival skills is also crucial.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/466034/original/file-20220530-14-np1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466034/original/file-20220530-14-np1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466034/original/file-20220530-14-np1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466034/original/file-20220530-14-np1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466034/original/file-20220530-14-np1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466034/original/file-20220530-14-np1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466034/original/file-20220530-14-np1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Floods in Gan in Béarn in 2018.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/pezon64/42709789225/">Bernard Pez/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Several initiatives, called <a href="https://www.recovery-observatory.org/drupal/en/node/811">“reconstruction observatories”</a>, have been carried out after major disasters – two examples are Haiti in 2021 and in Beirut after the 2019 port explosion. The aim is to coordinate satellite images to enable a detailed and dynamic assessment of damage to buildings, roads, farms, forests and more in the most affected areas, to monitor reconstruction planning, to reduce risks and to monitor changes over a three- to four-year time horizon.</p><img src="https://counter.theconversation.com/content/199357/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emilie Bronner ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'a déclaré aucune autre affiliation que son organisme de recherche.</span></em></p>Using space imagery can help guide relief efforts to critical areas during a natural disaster.Emilie Bronner, Représentante CNES au Secrétariat Exécutif de la Charte Internationale Espace et Catastrophes Majeures, Centre national d’études spatiales (CNES)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1948392022-12-09T15:49:18Z2022-12-09T15:49:18ZArrakhis: the tiny satellite aiming to reveal what dark matter is made of<figure><img src="https://images.theconversation.com/files/498940/original/file-20221205-25-h665s4.jpg?ixlib=rb-1.1.0&rect=239%2C0%2C5427%2C3494&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Milky Way over sand dunes in Cervantes, Australia.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/reverse-arch-milky-way-on-sand-1072692071">Nik Coli/Shutterstock</a></span></figcaption></figure><p>The European Space Agency (Esa) recently announced a new mission of its <a href="https://www.esa.int/About_Us/Business_with_ESA/Business_Opportunities/Science_Programme">science programme</a>: a small telescope orbiting the Earth dubbed <a href="https://www.cosmos.esa.int/web/call-for-missions-2021/selection-of-f2">Arrakhis</a>. But although its name is inspired by the sci-fi novel <a href="https://en.wikipedia.org/wiki/Dune_(novel)">Dune</a>, it will not be looking for sandworms or “spice” on a desert planet. </p>
<p>Instead, this nimble satellite will punch hugely above its weight and try to track down one of the most elusive and mysterious substances in the universe: <a href="https://theconversation.com/why-do-astronomers-believe-in-dark-matter-122864">dark matter</a>. This is the term given to the hypothetical invisible matter that is thought to be more abundant than normal matter and have a similar gravitational effect on its surroundings.</p>
<p>The mission is classified as fast (F), which means it is smaller, more focused and has a quicker turnaround (less than ten years to launch) than other types of Esa missions. The agency’s previous F-mission, selected in 2019, is called the <a href="https://www.cometinterceptor.space">Comet Interceptor</a>. Already parked at a stable point in the Solar System, this probe is waiting for a comet to show up and fly by it, something that’s due to happen around the time that Arrakhis launches in the early 2030s.</p>
<h2>Follow the light</h2>
<p>Since dark matter <a href="https://theconversation.com/dark-matter-the-mystery-substance-physics-still-cant-identify-that-makes-up-the-majority-of-our-universe-85808">still eludes detection</a>, the mission will target sources of light that are sensitive to it. We expect normal matter – the stuff that actually emits light, such as stars in galaxies – to move primarily under the influence of dark matter, which is more abundant. </p>
<p>We believe entire galaxies are moved to and fro by the underlying dark matter, like beacons spread across an invisible ocean. Their sailing is bumpy though, as dark matter is thought to be distributed unevenly across the universe, forming a <a href="https://theconversation.com/scientists-start-mapping-the-hidden-web-that-scaffolds-the-universe-124616">“cosmic web”</a> over vast distances, and having a more clumpy appearance on galaxy scales. Some of these clumps should be populated with small galaxies called <a href="https://esahubble.org/wordbank/dwarf-galaxy/">dwarf galaxies</a>, while others would be made up entirely of dark matter.</p>
<p>There is also debris left over from those dwarf galaxies that venture too close to the host galaxies they orbit. As the surrounding dark matter rips these galaxies apart through gravitational tides, they start to unravel into long streams of stars that wrap around vast swathes of space. These thin veils of light are another connection with the unseen. By counting and measuring their shapes, we can infer what type of particle dark matter is made of – and ultimately which cosmological model is the most accurate.</p>
<figure class="align-center ">
<img alt="Image of NGC 5907, a galaxy which hosts faint streams of stars that wrap all around it." src="https://images.theconversation.com/files/496311/original/file-20221120-26-cl1krw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/496311/original/file-20221120-26-cl1krw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496311/original/file-20221120-26-cl1krw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496311/original/file-20221120-26-cl1krw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496311/original/file-20221120-26-cl1krw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496311/original/file-20221120-26-cl1krw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496311/original/file-20221120-26-cl1krw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Like the Milky Way, the NGC 5907 galaxy hosts faint streams of stars that wrap all around it.</span>
<span class="attribution"><span class="source">wikipedia/R Jay Gabany (Blackbird Observatory) - collaboration; D.Martinez-Delgado(IAC, MPIA), J.Penarrubia (U.Victoria) I. Trujillo (IAC) S.Majewski (U.Virginia), M.Pohlen (Cardiff)</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The clumpiness in space is a robust prediction of our cosmological models, as it simply represents the outcome of gravity acting on matter. However, our models give conflicting predictions about the number of these clumps, which could be higher or lower depending on <a href="https://www.symmetrymagazine.org/article/is-dark-matter-cold-warm-or-hot">what type of particle or particles</a> we assume dark matter to be made up of. </p>
<p>In the “standard” model of cosmology, dark matter particles are assumed to be <a href="https://astronomynow.com/2020/01/12/hubble-finds-evidence-for-widely-held-cold-dark-matter-theory/">“cold”</a>, meaning they are heavy and slow moving (an example would be “weakly interacting massive particles”, <a href="https://theconversation.com/from-machos-to-wimps-meet-the-top-five-candidates-for-dark-matter-51516">or Wimps</a>). This implies that our Milky Way will contain hundreds of dark matter clumps, some of which will contain dwarf galaxies. But the problem is that we only see a few dozen dwarf galaxies around us, which is very puzzling. It could mean that most of these clumps are made of dark matter.</p>
<p>Cosmologists have other viable ideas though. For example, if dark matter is <a href="https://www.symmetrymagazine.org/article/is-dark-matter-cold-warm-or-hot">“warm”</a> - meaning that particles are much lighter and faster, such as <a href="https://www.symmetrymagazine.org/article/the-search-for-the-sterile-neutrino">sterile neutrinos</a> - there would be far fewer clumps to begin with. Observations can give us the final clue as to which model is right, but to get there, we first need an accurate <a href="https://www.cosmotography.com/images/dwarf_galaxy_dark_matter.html">census of dwarf galaxies</a> orbiting the Milky Way. </p>
<h2>The tip of the iceberg</h2>
<p>There are strong indications that the dwarf galaxies discovered so far near the Milky Way or other large galaxies are just the tip of the iceberg, and that <a href="https://news.fnal.gov/2020/04/the-milky-ways-satellites-help-reveal-link-between-dark-matter-halos-and-galaxy-formation/">many more remain hidden </a> behind the light of their hosts. Arrakhis will be able to discover this missing population even at large distances from us.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Figure of a galaxy simulated with cold dark matter (left) versus warm dark matter (right). There are many more clumps of cold dark matter that can host dwarf galaxies than warm dark matter ones." src="https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=298&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=298&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=298&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=374&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=374&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496320/original/file-20221120-48207-2cj8xd.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=374&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 galaxy simulated with cold dark matter (left) versus warm dark matter (right). There are many more clumps of cold dark matter that can host dwarf galaxies than warm dark matter ones.</span>
<span class="attribution"><span class="source">Aquarius/Virgo/ICC Durham University.</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Observing this faint starlight has proven to be challenging even for the largest telescopes on Earth, since it requires very deep imaging and surveying of large portions of the sky. Besides, the Earth’s atmosphere is a hindrance. Arrakhis will observe from space, with an innovative camera that probes deeper in both the optical and near-infrared part of the spectrum, and with a much wider field of view. (Incidentally, this type of camera can also <a href="https://satlantis.com/isim-170-has-successfully-arrived-at-the-international-space-station/">look back at Earth</a> with excellent resolution.)</p>
<p>The hundred or so Milky Way-like systems that will be observed are about 100 million light-years away, where <a href="https://earthsky.org/space/milky-way-normal-galaxy-outlier-saga/">only a few dwarf galaxies</a> have been discovered so far, and no stellar streams yet. When we know the number of soon-to-be discovered dwarf galaxies and <a href="https://theconversation.com/dance-of-galaxies-challenges-current-thinking-on-cosmology-91097">how they will be seen distributed in space</a>, we should be able to pin down the correct cosmological model. </p>
<p>Arrakhis will find many of the missing pieces in the puzzle that dark matter provides, complementing what we already know from the nearby universe and what we will learn in the future from other upcoming telescopes, such as <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid_overview">Euclid</a> or the <a href="https://www.lsst.org">Vera Rubin Observatory</a>.</p>
<p>The hope is that these detailed, combined observations will finally reveal the dark matter mystery, and help us understand what makes up the majority of matter in the cosmos.</p><img src="https://counter.theconversation.com/content/194839/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andreea Font 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>By spotting and counting tiny galaxies, we can work out how much dark matter is hiding in the cosmos.Andreea Font, Reader in Theoretical Astrophysics, Liverpool John Moores UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1955662022-12-01T23:04:24Z2022-12-01T23:04:24ZThe world finally has its first ‘parastronaut’. Can we expect anyone to be able to go to space one day?<figure><img src="https://images.theconversation.com/files/498420/original/file-20221201-18-1k07g3.jpeg?ixlib=rb-1.1.0&rect=25%2C11%2C1862%2C1238&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">NASA astronaut Winston E. Scott on an EVA in 1996.</span> <span class="attribution"><a class="source" href="https://images.nasa.gov/details-STS072-393-022">NASA JSC</a></span></figcaption></figure><p>The European Space Agency made history last week with the announcement of the first “parastronaut”, 41-year-old UK citizen John McFall.</p>
<p>He is the first candidate selected for the Parastronaut Feasibility project, <a href="https://www.esa.int/About_Us/Careers_at_ESA/ESA_Astronaut_Selection/Parastronaut_feasibility_project">described by ESA as</a> a “serious, dedicated and honest attempt to clear the path to space for a professional astronaut with a physical disability”.</p>
<p>McFall, a former Paralympic sprinter, had his right leg amputated after a motorcycle accident at age 19. </p>
<p>Most of us are familiar with images of gruelling astronaut selection tests and training from movies such as The Right Stuff. ESA seeks to answer the practical question of what changes to training and equipment need to be made for a physically disabled person to travel to space. </p>
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<h2>How are astronauts selected?</h2>
<p>NASA first selected astronauts, <a href="https://www.life.com/history/mercury-seven-photos-of-nasa-astronauts-in-training/">the Mercury Seven</a>, in 1959. Recruitment was limited to male military test pilots less than 40 years old, in excellent physical and mental health, and less than 1.8m tall (the Mercury capsule was tiny).</p>
<p>Today, NASA uses a similar basic eligibility screening. Applicants must have 20/20 vision (corrective lenses and laser eye surgery are okay) with blood pressure under 140/90 when seated and a height between 1.49 and 1.93m (to fit <a href="https://theconversation.com/what-does-it-take-to-do-a-spacewalk-skill-courage-and-being-able-to-wear-a-mens-size-medium-163256">available spacesuits</a>). </p>
<p>However, this is the easy part. Candidates endure several rounds of interviews and testing, and if lucky enough to be selected will need to pass the long-duration flight astronaut physical. It’s a gruelling week-long test of physical abilities necessary for space, such as agility and hand-eye coordination, as well as tolerance of extreme pressure and inertial (rotating) environments.</p>
<p>This is followed by a two-year training period mastering complex space hardware and software, performing simulated EVAs (spacewalks) in Houston’s <a href="https://www.nasa.gov/centers/johnson/pdf/167748main_FS_NBL508c.pdf">Neutral Buoyancy Laboratory</a>, and experiencing weightlessness during <a href="https://www.nasa.gov/analogs/parabolic-flight">parabolic flight</a>.</p>
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</strong>
</em>
</p>
<hr>
<p>Although I have described the NASA process here, similar programs are used across space agencies. Determining what adaptations to training are required to allow participation by physically disabled candidates will be one outcome of the parastronaut project.</p>
<h2>Astronaut diversity is improving</h2>
<p>Culturally, astronaut selection criteria have slowly evolved since the first all-male, all-military cohorts. The first female (and civilian) in space, Soviet cosmonaut <a href="https://starchild.gsfc.nasa.gov/docs/StarChild/whos_who_level2/tereshkova.html">Valentina Tereshkova</a>, flew on the Vostok 6 capsule in 1963.</p>
<p>It was another 15 years before NASA selected female astronauts, and a further five before <a href="https://www.nasa.gov/feature/sally-ride-first-american-woman-in-space/">Sally Ride</a> became the first US woman in space aboard the shuttle Challenger in 1983. The first NASA astronaut of colour, <a href="https://www.nasa.gov/subject/11054/guy-bluford/">Guion “Guy” Bluford</a>, flew in the same year.</p>
<p>The 2021 NASA astronaut class of ten candidates, <a href="https://www.nasa.gov/press-release/nasa-selects-new-astronaut-recruits-to-train-for-future-missions">Group 23</a>, included four women and several candidates from culturally diverse backgrounds. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A group of ten diverse people in dark blue jumpsuits standing outdoors on a sunny day" src="https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=382&fit=crop&dpr=1 600w, https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=382&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=382&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=480&fit=crop&dpr=1 754w, https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=480&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/498415/original/file-20221201-22-z07hr6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=480&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">NASA’s 2021 astronaut candidate class.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/press-release/nasa-selects-new-astronaut-recruits-to-train-for-future-missions">NASA</a></span>
</figcaption>
</figure>
<p>It would appear that diversity in astronaut selection has lagged behind society, and ESA has made a bold step with the parastronaut project. </p>
<h2>Levelling the playing field</h2>
<p>ESA has initially focused on candidates with a lower-limb disability. Astronauts primarily use their upper body to get around in weightlessness, and a lower-limb disability is unlikely to impair movement. In this respect, zero-g presents a level playing field. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Portrait of a smiling white man in a black and white polo shirt looking at the camera" src="https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=901&fit=crop&dpr=1 600w, https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=901&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=901&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1132&fit=crop&dpr=1 754w, https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1132&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/498417/original/file-20221201-24-isootg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1132&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">British doctor and Paralympian John McFall is a member of the ESA Astronaut Class of 2022.</span>
<span class="attribution"><a class="source" href="https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Astronauts/John_McFall">ESA - P. Sebirot</a></span>
</figcaption>
</figure>
<p>Issues are likely to arise when operating existing space hardware. The parastronaut study aims to determine what modifications to launch vehicles, spacesuits and other space systems would be necessary to allow a physically disabled astronaut to live and work in space. </p>
<p>There is precedent for an astronaut with a progressively disabling condition flying in space. NASA astronaut <a href="https://spacecenter.org/remembering-nasa-astronaut-rich-clifford/">Rich Clifford</a> was diagnosed with Parkinson’s disease in 1994 after noticing a lack of movement in his right arm when walking, shortly before his third scheduled shuttle flight.</p>
<p>NASA not only allowed him to launch aboard Atlantis in 1996 for his final mission, but scheduled Clifford for a six-hour EVA on the exterior of the Mir space station.</p>
<p>Although his experience was largely positive, Clifford did note he had difficulty donning his spacesuit due to limited motion of his right arm. The human-machine interface may present the biggest challenge for future parastronauts.</p>
<h2>Space is still risky and extreme</h2>
<p>In November 2021 we passed the milestone of <a href="https://www.npr.org/2021/11/10/1054575533/spacex-launch">600 humans having gone to space</a>. Compare that to the 674 <em>million</em> passengers who flew on US airlines in 2021 alone.</p>
<p>If we could travel back in time to when only 600 people had flown in aeroplanes, we would find the risk of flying considerably higher than today. This is where we are with spaceflight.</p>
<p>It remains a high-risk venture to an extreme environment with significant physical and mental challenges. We are still a long way from anyone being able to travel to space, although hopefully we won’t have to wait until billions of people have launched to reach a level of safety comparable to modern commercial aviation. </p>
<p>Our knowledge of the physical, mental and operational risks associated with spaceflight is still incomplete. Of the 600+ space travellers to date, only 70 have been female, and an understanding of gender difference in space health is only just beginning to emerge.</p>
<p>How would a physical disability affect an astronaut’s performance in space? We don’t know, but ESA is taking the first step in finding out. It would appear that space truly is the last frontier.</p><img src="https://counter.theconversation.com/content/195566/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steven Moore has received research funding from NASA and ESA. </span></em></p>The European Space Agency has recruited the world’s first-ever disabled astronaut. But we’re still a long way from space being accessible to all.Steven Moore, Professor, School of Engineering and Technology, CQUniversity AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1848182022-07-11T18:37:15Z2022-07-11T18:37:15ZSpace agriculture boldly grows food where no one has grown before<figure><img src="https://images.theconversation.com/files/473090/original/file-20220707-26-kg2bsz.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C1908%2C1916&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Satellite imagery monitors environmental changes to inform agricultural decisions. Agricultural patterns are distinctly visible in this near-vertical false colour infrared photography of farmland south of Khartoum, Sudan.</span> <span class="attribution"><a class="source" href="https://images.nasa.gov/details-sts066-84-038">(JSC/NASA)</a></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/space-agriculture-boldly-grows-food-where-no-one-has-grown-before" width="100%" height="400"></iframe>
<p>Whether to spend money on outer space exploration or to apply it to solve serious problems on Earth, like climate change and food shortages, is a contentious debate. But one argument in favour of space exploration highlights benefits that do, in fact, help study, monitor and address serious concerns like climate change and food production.</p>
<p>As access to space increases, the potential for terrestrial benefits directly tied to space exploration grow exponentially.</p>
<p>For example, agriculture has been improved significantly through the application of space-based advances to terrestrial challenges. It is now increasingly likely that food items have been produced with the assistance of space-based technologies, <a href="https://spinoff.nasa.gov/Spinoff2020/cg_2.html">like freeze-dried foods</a>, or through the use of <a href="https://nasaharvest.org/news/measuring-crop-characteristics-space">crop monitoring from space-based observatories</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a hand holds a growing small plant with a chart behind it" src="https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473089/original/file-20220707-20-4q2cod.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dwarf wheat photographed aboard the International Space Station in April 2002.</span>
<span class="attribution"><a class="source" href="https://images.nasa.gov/details-0300227">(NASA/MSFC)</a></span>
</figcaption>
</figure>
<h2>Monitoring farmlands</h2>
<p><a href="https://doi.org/10.1007/978-3-319-33438-7">Satellite monitoring</a> is arguably the most realized benefit of space for farming. Like mindful eyes in the sky, satellites watch over the farmlands across the globe day and night. Specialized sensors on relevant satellites (for example, <a href="https://landsat.gsfc.nasa.gov/data/">NASA’s Landsat</a>, <a href="https://www.esa.int/Enabling_Support/Operations/Envisat">the European Space Agency’s Envisat</a> and <a href="https://www.asc-csa.gc.ca/eng/satellites/radarsat/">the Canadian Space Agency’s RADARSAT</a>) monitor various parameters relevant to agriculture. </p>
<p>Sensors monitoring soil moisture can tell us when and how fast soils are drying, helping direct more efficient irrigation on a regional scale. Weather satellites help predict <a href="http://www.nasa.gov/feature/goddard/2021/nasa-at-your-table-the-space-agency-s-surprising-role-in-agriculture">drought, floods, precipitation patterns and plant disease outbreaks</a>. </p>
<p>Satellite data helps us <a href="https://www.smithsonianmag.com/innovation/predict-famine-before-strikes-180954945/">predict food insecurity threats or crop failures</a>.</p>
<h2>Plant science</h2>
<p>It’s not only lifeless machines that dwell in space. Humans have managed to survive and <a href="https://astrobotany.com/a-brief-history-of-plant-habitats-in-space/">grow plants in low-Earth orbit aboard several spacecraft and stations</a>. Space is the ultimate “<a href="https://www.esa.int/Science_Exploration/Space_Science/Extreme_space/Surviving_extreme_conditions_in_space">harsh environment</a>” for life to exist in, including plants, due to such novel stressors as cosmic radiation and lack of gravity.</p>
<p>Space biologist Anna-Lisa Paul describes plants as being able to “reach into their genetic toolbox and remake the tools they need” to adapt to the novel environment of space. The new tools and behaviours <a href="https://doi.org/10.1016/j.isci.2022.104687">expressed by plants under spaceflight conditions</a> could be used to solve challenges facing crops in Earth’s changing climate.</p>
<p>Researchers at NASA sent cotton seeds to the International Space Station to understand how cotton roots grow in the absence of gravity. The findings of the research will help develop <a href="https://www.agriculture.com/crops/growing-cotton-in-space-helps-identify-sustainable-production-practices">cotton plant varieties with a deeper root system to access and absorb water more efficiently from soil in drought-prone areas</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/LwwDIP36eb8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Space biologist Anna-Lisa Paul describes how plants respond to stress, and what that can teach us.</span></figcaption>
</figure>
<h2>Farming technologies</h2>
<p>Soon, humans will go to <a href="https://www.nasa.gov/specials/60counting/future.html">the moon</a> and <a href="https://www.nasa.gov/directorates/spacetech/6_Technologies_NASA_is_Advancing_to_Send_Humans_to_Mars">eventually to Mars</a>. While there, astronauts will have to grow their own food. </p>
<p>Space agencies have been working on specialized systems that provide the conditions necessary for plant cultivation in space. These systems are containers that can control the internal environment and grow plants without soil under LED lights. NASA’s research in <a href="https://spinoff.nasa.gov/indoor-farming">controlled environment systems to grow plants was foundational in developing the modern-day vertical farm sector</a> — indoor farms that grow crops in stacks without soil under the purple haze of LEDs.</p>
<p>Now a burgeoning industry, vertical farms are churning out enormous volumes of fresh and healthy leafy crops with a fraction of the water and nutrients that would be used in land-based farm systems. Vertical farms can be set up within cities, right where the demand lies, thereby cutting the need for long-distance transport. </p>
<p>As crops are grown indoors in controlled environments, vertical farms can substantially reduce the reliance on herbicides and pesticides, while recycling water and preventing nutrient runoff.</p>
<h2>Space agriculture, Earth benefits</h2>
<p>Considering the constraints of space, crop production techniques need to be more energy-efficient and require minimal human input. Crops need to also be nutrition-rich, with the ability to withstand high-stress environments. These features are also desirable for crops on Earth.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="plants grow in stacked rows under purple uv light" src="https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473080/original/file-20220707-26-zkqyrs.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">Hydroponic and vertical farming was developed to allow crops to grow without soil or sunshine.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Scientists are developing a more <a href="https://doi.org/10.1038/s41467-021-26238-3">resource-efficient potato crop where the whole plant can be consumed, including roots, shoots and fruits</a>. Such crops will play a pivotal role in addressing food and nutritional security on Earth and in space.</p>
<p>Space exploration has served as a major driver for technological advances. The renewed interest in space can only benefit agriculture here on Earth by providing new opportunities to improve agriculture. Innovations that are quite literally out-of-this-world can provide us tools to tackle food production under the looming threats posed by global climate change.</p><img src="https://counter.theconversation.com/content/184818/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Thomas Graham receives funding from OMAFRA, NSERC, Canadian Space Agency, Commercial partners on government grants. </span></em></p><p class="fine-print"><em><span>Ajwal Dsouza 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>Technologies being developed for growing food in space have contributed to advances in agriculture and crops on Earth.Ajwal Dsouza, PhD Candidate, Environmental Sciences, University of GuelphThomas Graham, Assistant Professor, Environmental Sciences, University of GuelphLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1847732022-06-13T12:00:59Z2022-06-13T12:00:59ZGaia mission: five insights astronomers could glean from its latest data<figure><img src="https://images.theconversation.com/files/468179/original/file-20220610-35158-mfvhp4.jpg?ixlib=rb-1.1.0&rect=27%2C32%2C3076%2C2003&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Gaia mapping the stars of the Milky Way.</span> <span class="attribution"><span class="source">ESA/ATG medialab; background: ESO/S. Brunier</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>The European Space Agency’s (Esa) <a href="https://theconversation.com/gaia-mission-releases-map-of-more-than-a-billion-stars-heres-what-it-can-teach-us-95602">Gaia mission</a> has just released new data. The Gaia satellite was launched in 2013, with the aim of measuring the precise positions of a billion stars. In addition to measuring the stars’ positions, speeds and brightness, the satellite has collected data on a huge range of other objects.</p>
<p>There’s a lot to <a href="https://theconversation.com/how-were-helping-the-gaia-mission-map-a-billion-stars-to-unparalleled-precision-65602">make astronomers excited</a>. Here are five of our favourite insights that the data might provide.</p>
<h2>1. Secrets of our galaxy’s past and future</h2>
<p>Everything in space is moving, and the stars are no exception. The latest release of data contains the largest three-dimensional map of the Milky Way ever produced - showing how the stars in our galaxy are travelling. Previous data included the motions of stars in two dimensions: up-down and left-right (known collectively as stars’ <a href="https://sci.esa.int/web/gaia/-/60224-parallax-and-proper-motion-on-the-sky">proper motions</a>). But the latest data also shows how quickly stars are moving away from us or towards us, something we call the stars’ radial velocities.</p>
<p>By combining the radial velocity with the proper motions, we can find out how quickly stars are moving in three dimensions as they orbit the Milky Way. This means we now have not only the best map of where the galaxy’s stars are now, but we can track their motions forward to see how things will change, and backward to see how things used to be. </p>
<p>This can tell us things about our galaxy’s history, such as which stars may have come from other galaxies and merged with our own in the past. Radial velocity measurements can also help us find hidden objects, such as planets and <a href="https://theconversation.com/exoplanet-discovery-blurs-the-line-between-large-planets-and-small-stars-124150">brown dwarfs</a> (extremely faint stars with low mass), from the tiny wobbles they cause as they orbit a host star.</p>
<h2>2. Details of how stars die</h2>
<p>Gaia is not just measuring the stars in our own galaxy, it also measures those in the neighbouring Andromeda galaxy. The data includes something called Gaps: <a href="https://www.cosmos.esa.int/web/gaia/newsletter/contents">the Gaia Andromeda photometric survey</a>. A photometric survey measures the brightness of stars and how they change over time. With Gaps, Gaia has measured the brightness over time for every star in the direction of the Andromeda galaxy.</p>
<p>That includes 1.2 million stars. Some of those will be foreground stars in the Milky Way that happened to be in the way, but it should include roughly the brightest 1% of stars in the Andromeda galaxy. This will allow us to study the way that the largest, most luminous stars in Andromeda change in brightness, telling us about their evolution and where they are in their life cycles.</p>
<p>This could tell us more about old stars that are reaching the ends of their lives - some of which could go on to produce supernovas (huge explosions) eventually.</p>
<h2>3. The truth about the universe’s strange expansion</h2>
<p><a href="https://earthsky.org/astronomy-essentials/definition-what-is-a-quasar/">Quasars</a>, extremely energetic cores of galaxies at the edge of the observable universe, are the most luminous objects in the universe and the most distant objects we can see. And the new data includes measurements of 1.1 million of them. Quasars contain supermassive black holes that are caught in a violent feeding frenzy. In addition to these confirmed quasars, Gaia has found a further 6.6 million quasar candidates. </p>
<figure class="align-center ">
<img alt="Schematic image of the universe's expansion." src="https://images.theconversation.com/files/292202/original/file-20190912-190012-1sio7rp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/292202/original/file-20190912-190012-1sio7rp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/292202/original/file-20190912-190012-1sio7rp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/292202/original/file-20190912-190012-1sio7rp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/292202/original/file-20190912-190012-1sio7rp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/292202/original/file-20190912-190012-1sio7rp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/292202/original/file-20190912-190012-1sio7rp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Universe’s expansion.</span>
<span class="attribution"><span class="source">NASA/WMAP</span></span>
</figcaption>
</figure>
<p>This potentially vastly increases the number of known quasars, and that could be very important because they let us measure the distance to the furthest reaches of the universe. This in turn lets us measure how quickly the universe is expanding. Being able to measure that more accurately is important, because we have two <a href="https://theconversation.com/the-universes-rate-of-expansion-is-in-dispute-and-we-may-need-new-physics-to-solve-it-100154">conflicting measurements of the expansion</a>, and we don’t know which one is right – the problem is called “the Hubble tension”.</p>
<h2>4. How many asteroids have moons</h2>
<p>Not everything Gaia is studying is so far from home. The data contains 158,000 objects in our own Solar System. That includes new measurements of 156,000 known asteroids, telling us exactly what paths they follow as they orbit the Sun. </p>
<p>Not only that, but the Gaia team has shown that they are able to find moons orbiting asteroids, based on how the moons make the asteroids wobble. A few hundred asteroids with moons are already known, but Gaia can find asteroid moons even when the moon is too small to see directly. It can also measure the positions of asteroids so accurately that it sees the slight wobble in the position caused by a moon’s gravity. Esa says the latest data contains at least one such new moon, but there could be a lot more.</p>
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<img alt="Image of asteroids around the Sun as seen by Gaia." src="https://images.theconversation.com/files/468396/original/file-20220613-43540-h2o15v.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/468396/original/file-20220613-43540-h2o15v.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=604&fit=crop&dpr=1 600w, https://images.theconversation.com/files/468396/original/file-20220613-43540-h2o15v.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=604&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/468396/original/file-20220613-43540-h2o15v.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=604&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/468396/original/file-20220613-43540-h2o15v.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=759&fit=crop&dpr=1 754w, https://images.theconversation.com/files/468396/original/file-20220613-43540-h2o15v.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=759&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/468396/original/file-20220613-43540-h2o15v.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=759&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Asteroids around the Sun as seen by Gaia. Each asteroid is a segment representing its motion over 10 days (with blue representing the inner solar system).</span>
<span class="attribution"><span class="source">ESA/Gaia/DPAC</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>Gathering better data about asteroids can tell us about the chaos of the early Solar System when the larger planets threw smaller planets and asteroids into new orbits around the Sun and led to the solar system of today.</p>
<h2>5. How stars form and operate</h2>
<p>Our Sun is a solitary star, but many stars have companions – <a href="https://www.atnf.csiro.au/outreach/education/senior/astrophysics/binary_intro.html">orbiting each other around a shared centre</a>. The new data contains the first taste of Gaia’s catalogue of such multiple-star systems. This is an initial list, with the full catalogue to come in a later data release, but it already contains 813,000 binary (two-star) systems.</p>
<p>Binary stars can tell us a lot about how stars work and how they are formed. This is especially true for what are called eclipsing binary systems. These are binary systems that happen to be lined up so that the stars pass in front of each other from our point of view. Eclipsing binaries are special because we can take measurements of them to work out all the physical properties of the system, such as the stars’ masses and sizes, and how far away they are. This allows us to learn far more than we could from studying single stars.</p>
<p>This new data will excite astrophysicists around the world, and we can’t wait to get stuck into it to see what we can find. We might have some of these answers in the next few months, while others might take longer.</p><img src="https://counter.theconversation.com/content/184773/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Adam McMaster receives funding from the Science and Technology Facilities Council, DISCnet, and the Open University Space SRA.</span></em></p><p class="fine-print"><em><span>Andrew Norton does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>New data may settle dispute about the universe’s true expansion rate.Adam McMaster, PhD Candidate, Astronomy, The Open UniversityAndrew Norton, Professor of Astrophysics Education, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1842732022-06-02T18:22:54Z2022-06-02T18:22:54ZUkraine recap: bogged down in the bloody Donbas region<figure><img src="https://images.theconversation.com/files/466659/original/file-20220601-48614-mxke6n.jpg?ixlib=rb-1.1.0&rect=0%2C8%2C5703%2C3608&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">EPA-EFE/stringer</span>, <span class="license">Fourni par l'auteur</span></span></figcaption></figure><p>It’s now over 14 weeks since Vladimir Putin sent Russia’s military machine into Ukraine expecting a relatively easy victory. It’s fair to say that the “special military operation” is not panning out the way the Russian president or his planners had envisaged. </p>
<p>The main focus of the fighting continues to be in the Donbas region in the country’s east, where Russian territorial gains are being met with a terrible butcher’s bill on both sides. Portsmouth University’s military strategist, Frank Ledgwidge, says Russia has <a href="https://theconversation.com/ukraine-war-despite-russias-success-in-donbas-this-is-only-the-end-of-the-beginning-183955">lost more troops</a> killed since February 24 than in ten years of fighting in Afghanistan – implying that well over 40,000 Russian soldiers have been taken out of the game. Ukraine’s casualties, Ledwidge estimates, are also grievous. </p>
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Read more:
<a href="https://theconversation.com/ukraine-war-despite-russias-success-in-donbas-this-is-only-the-end-of-the-beginning-183955">Ukraine war: despite Russia's success in Donbas, this is only the end of the beginning</a>
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<p>Ledwidge’s regular analysis has so far proved remarkably prescient: you may remember he predicted on day two of the conflict that Ukraine’s armed forces would put up stiff resistance and rightly that the battle for the Donbas would be protracted and bloody. </p>
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<p>Meanwhile, the first Russian soldier has been convicted in a war crimes trial and sentenced to life imprisonment. Vadim Shishimarin, 21, was sentenced for the killing of a 62-year-old man who was shot in the head in a village in the northeastern Sumy region in the opening days of the war. </p>
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<img alt="Ukraine Recap weekly email newsletter" src="https://images.theconversation.com/files/449743/original/file-20220303-4351-1xhaozt.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/449743/original/file-20220303-4351-1xhaozt.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/449743/original/file-20220303-4351-1xhaozt.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/449743/original/file-20220303-4351-1xhaozt.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/449743/original/file-20220303-4351-1xhaozt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/449743/original/file-20220303-4351-1xhaozt.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/449743/original/file-20220303-4351-1xhaozt.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><strong><em>This is our weekly recap of expert analysis of the Ukraine conflict.</em></strong>
<em>The Conversation, a not-for-profit news group, works with a wide range of academics across its global network to produce evidence-based analysis. Get these recaps in your inbox every Thursday. <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=WeeklyRecapTop">Subscribe here</a>.</em></p>
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<p>Legal scholar Robert Goldman of American University in Washington – an expert on the law of war – believes that, while Ukraine is entitled to try the young tank commander for the murder, it may <a href="https://theconversation.com/war-crimes-trial-of-russian-soldier-was-perfectly-legal-but-that-doesnt-make-it-wise-183586">not have been wise to pursue the case</a> while the war still rages and in a civilian court. He also cautions that while Ukraine may well have observed due process of law in presenting the prosecution, not that this precedent has been set, there’s no guaranteeing Russia will be so scrupulous.</p>
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Read more:
<a href="https://theconversation.com/war-crimes-trial-of-russian-soldier-was-perfectly-legal-but-that-doesnt-make-it-wise-183586">War crimes trial of Russian soldier was perfectly legal – but that doesn't make it wise</a>
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<p>Another big item on the news agenda at the moment is the cost of living crisis, and war in Ukraine is exacerbating that considerably. The sharp increase in oil and gas prices, as well as riding food prices and shortage, can all – at least in part – be attributed to Putin’s war. </p>
<p>Birmingham University’s Stefan Wolff and his collaborator Tatyana Malyarenko of the National University of Odesa have taken a detailed look at the <a href="https://theconversation.com/ukraine-war-rising-food-prices-are-not-the-only-global-economic-fallout-183577">economic fallout from the conflict</a> and how this is likely to play into global political instability. One largely unforeseen consequence, they write, is the way this is affecting the US relationship with China – which will bear watching in the weeks and months ahead.</p>
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Read more:
<a href="https://theconversation.com/ukraine-war-rising-food-prices-are-not-the-only-global-economic-fallout-183577">Ukraine war: rising food prices are not the only global economic fallout</a>
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<h2>The diplomatic front</h2>
<p>One aspect of China-US relations in the news this week has involved the US stance on Taiwan. US president Joe Biden appeared to be rewriting America’s policy of “strategic ambiguity”, when he made a recent pledge to the effect that the US would take military action to defend Taiwan if China launched an invasion. Russia’s invasion has, as you’d expect, focused White House minds on the possibility that this might indeed come to pass. </p>
<p>Christoph Bluth and Owen Greene, international relations experts at the University of Bradford, believe that in the event of a Chinese invasion of Taiwan, the US will face a <a href="https://theconversation.com/how-ukraine-war-could-boost-tensions-between-us-and-china-over-future-of-taiwan-183745?notice=Article+has+been+updated.">completely different set of challenges</a> to those posed by Putin’s aggression in Ukraine.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/how-ukraine-war-could-boost-tensions-between-us-and-china-over-future-of-taiwan-183745">How Ukraine war could boost tensions between US and China over future of Taiwan</a>
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<p>Closer to home, meanwhile, there has been a spate of intense diplomatic activity sparked by Russia’s aggression. The last Ukraine recap focused on the decision of Finland and Sweden to seek membership of Nato, and this week Owen Greene has taken a closer look at the <a href="https://theconversation.com/sweden-a-history-of-neutrality-ends-after-200-years-183583">history of Swedish neutrality</a> since the Napoleonic wars. This stance began to change after Russia annexed the Crimea when the country began to seek closer defence cooperation with its neighbours and, through Nato members Denmark and Norway, with the North Atlantic alliance itself.</p>
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Read more:
<a href="https://theconversation.com/sweden-a-history-of-neutrality-ends-after-200-years-183583">Sweden: a history of neutrality ends after 200 years</a>
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<p>Denmark is also examining its defensive alliances and is voting on whether to end its opt-out from the European Union’s defence policy. It’s a significant move, as the EU has been bolstering its own defensive capabilities of late, so a vote in favour of ending the opt-out – according to Imelda Maher of University College Dublin and Dermot Hodson of Birkbeck, University of London – would <a href="https://theconversation.com/why-denmark-is-voting-on-its-defence-relationship-with-the-eu-and-what-it-says-about-democracy-in-europe-182732">accelerate that growth</a>.</p>
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Read more:
<a href="https://theconversation.com/why-denmark-is-voting-on-its-defence-relationship-with-the-eu-and-what-it-says-about-democracy-in-europe-182732">Why Denmark is voting on its defence relationship with the EU – and what it says about democracy in Europe</a>
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<h2>Collateral damage</h2>
<p>Just a few months ago, the European Space Agency (Esa) was preparing for the launch of the Rosalind Franklin rover on its trip to Mars, part of the ExoMars mission, a collaboration between Europe and Russia. Russia was to have provided several key components of the mission, including a rocket to launch it on its journey and the radioactive heaters to keep the batteries of the rover warm in the cold Martian nights.</p>
<p>Now, says space scientist Andrew Coates of University College London, Esa will need to <a href="https://theconversation.com/our-mars-rover-mission-was-suspended-because-of-the-ukraine-war-heres-what-were-hoping-for-next-183927">find new partners for the mission</a>. If this turns out to be Nasa, as is widely thought, this will further widen Russia’s rift with the west.</p>
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Read more:
<a href="https://theconversation.com/our-mars-rover-mission-was-suspended-because-of-the-ukraine-war-heres-what-were-hoping-for-next-183927">Our Mars rover mission was suspended because of the Ukraine war – here's what we're hoping for next</a>
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<p>And finally, while you will have seen Russian and Belarus tennis stars competing in the French Open this week, you won’t be seeing these top players at Wimbledon, which has banned all competitors from the two countries. The likes of men’s world number two Daniil Medvedev, men’s number eight Andrey Rublev, and Belarusian former women’s world number two Aryna Sabalenka have been allowed to play as individuals rather than representing their respective countries. </p>
<p>As Leon Davis of Teeside University and Mike Duignan of the University of Surrey – both experts in event management – observe here, any of these players who openly express support for the Russian invasion <a href="https://theconversation.com/french-open-understanding-why-russian-and-belarusian-tennis-players-are-competing-despite-wimbledon-ban-181823">will face sanctions</a> and many of them have won plaudits for openly opposing the war. But, caution Davis and Duignan, even those Russian and Belarusian players who don’t actually live in their birth country any more are likely to have families there who could be endangered if they are too outspoken against the invasion.</p>
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Read more:
<a href="https://theconversation.com/french-open-understanding-why-russian-and-belarusian-tennis-players-are-competing-despite-wimbledon-ban-181823">French Open: understanding why Russian and Belarusian tennis players are competing despite Wimbledon ban</a>
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<p><em>Ukraine Recap is available as a weekly 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/184273/count.gif" alt="The Conversation" width="1" height="1" />
A digest of the week’s coverage of the war against Ukraine.Jonathan Este, Senior International Affairs Editor, Associate EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1839272022-05-26T12:58:03Z2022-05-26T12:58:03ZOur Mars rover mission was suspended because of the Ukraine war – here’s what we’re hoping for next<figure><img src="https://images.theconversation.com/files/465514/original/file-20220526-23-yco451.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C2880%2C1784&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Oxia Planum on Mars – where the rover was set to land.</span> <span class="attribution"><span class="source">Nasa</span></span></figcaption></figure><p>Just a few months ago, we were confidently expecting to launch our rover, Rosalind Franklin, to Mars in September as part of the ExoMars mission, a collaboration between Europe and Russia. The <a href="https://theconversation.com/decades-of-attempts-show-how-hard-it-is-to-land-on-mars-heres-how-we-plan-to-succeed-in-2021-69734">landing was planned</a> for June 2023. Everything was ready: the rover, the operations team and the eager scientists. </p>
<p>The final preparations started in February 21, with part of our team heading to Turin, Italy, to carry out the final alignment and calibration tests. All was going well, though some of the team were slightly delayed by Storm Eunice in the UK. Three days later, they had nevertheless finished the work – leaving some wonderful data, which would help us decide where Rosalind would drill on Mars. The industry team started packing the rover, which was ready to be shipped to the launch site. </p>
<p>Then, a storm far more powerful and tragic than Eunice descended on Ukraine: Russia’s invasion. The situation developed in the next days and weeks, leading to a series of emergency meetings. On March 17, the European Space Agency (Esa)‘s council and member states decided to <a href="https://www.bbc.co.uk/news/science-environment-60782932">suspend our mission</a>. We won’t know for sure what happens next until a study by Esa and industry partners reports back in July – but there are causes for optimism.</p>
<p>The Rosalind Franklin rover is unique among all the rovers planned for Mars. It can drill deeper than any before it – up to 2 metres below the harsh surface. This is important as the subsurface is protected from harmful radiation, and could therefore contain signs of past or present life.</p>
<p>Rosalind’s instruments include our PanCam, which is a camera that will do geology and atmospheric science on Mars – complemented by the other cameras and a sub-surface sounding radar. Rosalind will also collect pristine samples from below the surface which will be deposited in the “analytical drawer”, where three instruments will do mineralogy and search for signs of life. </p>
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<img alt="Image of the ExoMars rover on top of landing platform." src="https://images.theconversation.com/files/465513/original/file-20220526-13-6o194p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/465513/original/file-20220526-13-6o194p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/465513/original/file-20220526-13-6o194p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/465513/original/file-20220526-13-6o194p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/465513/original/file-20220526-13-6o194p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/465513/original/file-20220526-13-6o194p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/465513/original/file-20220526-13-6o194p.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">
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<span class="caption">ExoMars rover on top of landing platform.</span>
<span class="attribution"><span class="source">Thales Alenia Space/ESA</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Some 3.8 billion years ago, at the same time as life was emerging on Earth, Mars was habitable too. There is evidence from orbiters and landers of water on the surface then – there would have been clouds, rain and a thick atmosphere. There was also a global protective magnetic field, and volcanos. This means Mars essentially had all the right ingredients for life – carbon, hydrogen, nitrogen, oxygen, phosphorus and sulphur. If life emerged there like it did on Earth, we were on a track to find it. </p>
<p>The climate <a href="https://theconversation.com/how-did-mars-lose-its-habitable-climate-the-answer-is-blowing-in-the-solar-wind-50258">has changed significantly</a> since Mars lost its magnetic field 3.8 billion years ago, though. The planet is now is dry, cold, has a thin atmosphere and a surface hostile for life. But below the surface, some living species may have survived, or remains of them could be conserved.</p>
<p>Other missions to Mars are looking for life too. The amazing Nasa Perseverance rover <a href="https://theconversation.com/mars-perseverance-rover-set-for-nail-biting-landing-heres-the-rocket-science-154886">landed in February 2021</a>. Its scientists are partly guided by images from a Nasa helicopter on the planet, called Ingenuity, and it recently reached an ancient river delta. </p>
<p>Perseverance is collecting samples from Jezero crater, ready to be brought back to powerful labs on Earth by the <a href="https://theconversation.com/plan-to-bring-back-rocks-from-mars-is-our-best-bet-for-finding-clues-of-past-life-95797">Mars sample return missions</a>. The results will hopefully complement those from Rosalind Franklin – which will examine deeper samples from a different and slightly older site, Oxia Planum, where there is also abundant evidence of a watery past.</p>
<h2>Options for Rosalind</h2>
<p>Russia was meant to help launch Rosalind Franklin on one of its rockets. While a European-built spacecraft would then take it to Mars, a Russian-built platform would again be needed to land it. Russia was also meant to provide radioactive heaters to keep the batteries of the rover warm in the cold Martian nights.</p>
<p>Now, Esa is looking at options. Given that continuing with Russia in 2024 is most unlikely, the main possibilities are either Esa going it alone, or teaming up with a partner such as Nasa. Esa’s new <a href="https://www.esa.int/Enabling_Support/Space_Transportation/Launch_vehicles/Ariane_6">Ariane-6 rocket</a>, which is nearly ready, could help launch the rover, as could a SpaceX rocket. For the lander and heaters, Esa would need to develop these alone or in collaboration with Nasa, by adapting existing technology.</p>
<p>It could therefore take time. What’s more, because of the way the planets orbit the Sun, there are opportunities for launches to Mars only every two years: in 2024, 2026 and so on. My expectation is that 2028 is most likely for our mission, but it will require hard work. The positive thing is that Esa and the member states are still keen to go ahead, and we are eagerly looking forward to the launch whenever that will be.</p>
<p>Ultimately, life changed for the Rosalind Franklin team on February 24. I’ve been working on the mission since 2003, when we first proposed a camera system for what became ExoMars. We had already provided the “stereo camera system” for Esa’s ill-fated Beagle 2, which very nearly worked when it landed on Christmas Day 2003. But orbiter images later showed that the last solar panel didn’t quite unfurl, so communications with Earth <a href="https://theconversation.com/how-we-found-our-lost-mars-lander-after-a-decade-of-searching-and-whats-next-85374">were impossible</a>. The wait for data from the Martian surface for our team goes on.</p>
<p>There is no getting away from the huge disappointment we felt when the ExoMars Rosalind Franklin rover that we had worked on for almost 20 years was suspended. But it was ultimately a necessary and understandable step, and we now look forward to a future launch. </p>
<p>This still is cutting-edge science, and it will be for the rest of this decade. Due to the uniquely deep drilling, Rosalind Franklin still may be the first mission to find <a href="https://theconversation.com/our-rover-could-discover-life-on-mars-heres-what-it-would-take-to-prove-it-89625">signs of life</a> in space.</p><img src="https://counter.theconversation.com/content/183927/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Coates receives funding at UCL-MSSL from UK Space Agency and from STFC-UKRI, UK. He is PI of the PanCam instrument on the ExoMars Rosalind Franklin rover, leading an international team from UK, Germany, Switzerland, Austria and others. He is currently on the board of the Centre for Planetary Sciences at UCL-Birkbeck, a member of STFC Science Board, and is President of the Society for Popular Astronomy (popastro), UK.</span></em></p>The European space agency will need both a launch vehicle and a lander platform to launch its ExoMars rover without help from Russia.Andrew Coates, Professor of Physics, Deputy Director (Solar System) at the Mullard Space Science Laboratory, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1802212022-04-21T18:38:29Z2022-04-21T18:38:29ZSpace Blocs: The future of international cooperation in space is splitting along lines of power on Earth<figure><img src="https://images.theconversation.com/files/458928/original/file-20220420-20-i1aamw.jpg?ixlib=rb-1.1.0&rect=305%2C224%2C5604%2C3440&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In the next decade, both a U.S.-led group and a collaboration between Russia and China aim to set up bases on the Moon.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/russia-and-china-chess-standoff-royalty-free-image/934301722?adppopup=true">Theasis/iStock via Getty Images</a></span></figcaption></figure><p>Even <a href="https://doi.org/10.1093/ia/iiz190">during times of conflict</a> on the ground, space has historically been an arena of collaboration among nations. But trends in the past decade suggest that the nature of cooperation in space is shifting, and fallout from Russia’s invasion of Ukraine has highlighted these changes. </p>
<p><a href="https://svetlabenitzhak.com/">I’m an international relations scholar</a> who studies power distributions in space – who the main players are, what capabilities they possess and whom they decide to cooperate with. Some scholars predict a future in which <a href="https://www.routledge.com/The-International-Politics-of-Space/Sheehan/p/book/9780415399173?source=igodigital">single states</a> pursue various levels of <a href="https://www.routledge.com/Astropolitik-Classical-Geopolitics-in-the-Space-Age/Dolman/p/book/9780714681979">dominance</a>, while others foresee a scenario in which <a href="https://www.routledge.com/Security-and-Stability-in-the-New-Space-Age-The-Orbital-Security-Dilemma/Townsend/p/book/9780367432072?source=igodigital">commercial entities bring nations together</a>.</p>
<p>But I believe that the future may be different. In the past few years, groups of nations with similar strategic interests on Earth have come together to further their interests in space, forming what I call “space blocs.”</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A logo of the ISS surrounded by the flags of all the countries that support it." src="https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458934/original/file-20220420-24727-sjkw6x.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"></a>
<figcaption>
<span class="caption">The International Space Station is the quintessential example of international collaboration in space.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:ISS_emblem.png#/media/File:ISS_emblem.png">NASA via WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>From state-led space efforts to collaboration</h2>
<p>The U.S. and the Soviet Union dominated space activities during the Cold War. Despite tensions on the ground, both <a href="https://www.sup.org/books/title/?id=31357">acted carefully to avoid causing crises</a> and even <a href="https://doi.org/10.1093/ia/iiz190">cooperated on a number of projects</a> in space. </p>
<p>As <a href="https://space.oscar.wmo.int/spaceagencies">more countries</a> developed their own space agencies, several international collaborative groups emerged. These include the <a href="https://www.unoosa.org/oosa/index.html">United Nations Office for Outer Space Affairs</a>, the <a href="https://www.unoosa.org/oosa/en/ourwork/copuos/index.html">United Nations Committee on the Peaceful Uses of Outer Space</a> and the <a href="https://public.ccsds.org/default.aspx">Consultative Committee for Space Data Systems</a>. </p>
<p>In 1975, 10 European nations founded the <a href="https://www.esa.int/">European Space Agency</a>. In 1998 the U.S. and Russia joined efforts to build the International Space Station, which is now <a href="https://www.kennedyspacecenter.com/blog/the-20-most-frequently-asked-questions-about-the-international-space-station">supported by 15 countries</a>. </p>
<p>These multinational ventures were primarily focused on scientific collaboration and data exchange.</p>
<h2>The emergence of space blocs</h2>
<p>The European Space Agency, which now includes 22 nations, could be considered among the first space blocs. But a more pronounced shift toward this type of power structure can be seen after the end of the Cold War. Countries that shared interests on the ground began coming together to pursue specific mission objectives in space, forming space blocs.</p>
<p>In the past five years, several new space blocs have emerged with various levels of space capabilities. These include the <a href="https://au.int/en/treaties/statute-african-space-agency">African Space Agency</a>, with 55 member states; the <a href="https://www.gob.mx/sre/en/articulos/signing-of-the-convention-establishing-alce-the-latin-american-and-caribbean-space-agency-283235?idiom=en">Latin American and Caribbean Space Agency</a>, with seven member states; and the <a href="https://trends.aeroexpo.online/project-75745.html">Arab Space Coordination Group</a>, with 12 Middle Eastern member states. </p>
<p>These groups allow for nations to collaborate closely with others in their blocs, but the blocs also compete with one another. Two recent space blocs – the <a href="https://www.nasa.gov/specials/artemis-accords/index.html">Artemis Accords</a> and the <a href="https://spacenews.com/china-russia-to-cooperate-on-lunar-orbiter-landing-missions/">Sino-Russian lunar agreement</a> – are an example of such competition.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Buzz Aldrin in a spacesuit on the surface of the Moon next to the U.S. flag." src="https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=606&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=606&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=606&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=761&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=761&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458935/original/file-20220420-22-vcz8q0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=761&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">No human has been on the Moon in 50 years, but in the next decade, both the U.S.-led Artemis Accords and a Chinese-Russian mission aim to establish Moon bases.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/File:Buzz_salutes_the_U.S._Flag.jpg">NASA/Neil Armstrong via WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>Race to the Moon</h2>
<p>The <a href="https://www.nasa.gov/specials/artemis-accords/index.html">Artemis Accords</a> were launched in October 2020. They are led by the U.S. and currently include 18 country members. The group’s goal is to return people to the Moon by 2025 and establish a governing framework for exploring and mining on the Moon, Mars and beyond. The mission aims to build a research station on the south pole of the Moon with a supporting lunar space station called <a href="https://www.nasa.gov/gateway/overview">the Gateway</a>.</p>
<p>Similarly, in 2019, Russia and China agreed to collaborate on a <a href="https://spacenews.com/china-russia-to-cooperate-on-lunar-orbiter-landing-missions/">mission to send people</a> to the south pole of the Moon by 2026. This joint Sino-Russian mission also aims to eventually build a <a href="https://www.space.com/russia-china-moon-research-station-agreement">Moon base and place a space station</a> in lunar orbit. </p>
<p>That these blocs do not collaborate to accomplish similar missions on the Moon indicates that strategic interests and rivalries on the ground have been transposed to space.</p>
<p><a href="https://www.nasa.gov/specials/artemis-accords/index.html">Any nation can join the Artemis Accords</a>. But Russia and China – along with a number of their allies on Earth – have not done so because some perceive the accords as an effort <a href="https://theconversation.com/artemis-accords-why-many-countries-are-refusing-to-sign-moon-exploration-agreement-148134">to expand the U.S.-dominated international order</a> to outer space.</p>
<p>Similarly, Russia and China plan to open their future lunar research station <a href="https://www.space.com/russia-china-moon-research-station-agreement">to all interested parties</a>, but no Artemis country has expressed interest. The European Space Agency has even <a href="https://www.esa.int/Newsroom/Press_Releases/Redirecting_ESA_programmes_in_response_to_geopolitical_crisis">discontinued several joint projects</a> it had planned with Russia and is instead expanding its partnerships with the U.S. and Japan.</p>
<h2>The impact of space blocs on the ground</h2>
<p>In addition to seeking power in space, countries are also using space blocs to strengthen their spheres of influence on the ground.</p>
<p>One example is the <a href="http://www.apsco.int/">Asia-Pacific Space Cooperation Organization</a>, which was formed in 2005. Led by China, it <a href="https://spacewatch.global/2018/11/asia-pacific-space-cooperation-organisation-members-celebrate-tenth-anniversary/">includes</a> Bangladesh, Iran, Mongolia, Pakistan, Peru, Thailand and Turkey. </p>
<p>While its broad goal is the development and launch of satellites, the organization’s <a href="https://trends.aeroexpo.online/project-75745.html">major aim</a> is to expand and normalize the use of the Chinese BeiDou navigation system – the Chinese version of GPS. Countries that use the system could become dependent on China, as is the <a href="https://spacewatch.global/2016/11/irans-growing-dependency-on-chinas-beidou-satellite-navigation/">case of Iran</a>. </p>
<h2>The role of private space companies</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A Falcon9 rocket launching off." src="https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=902&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=902&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=902&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1133&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1133&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458936/original/file-20220420-17-5lvolu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1133&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Private companies are now major players in space, but launches – like SpaceX’s many missions – are still under the jurisdiction of the companies’ home nations.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nasakennedy/49420609803/in/photostream/">NASA/Tony Green</a></span>
</figcaption>
</figure>
<p>There has been tremendous <a href="https://www.morganstanley.com/ideas/investing-in-space">growth of commercial activities in space</a> in the past decade. As a result, some scholars see a future of space cooperation defined by <a href="https://www.routledge.com/Security-and-Stability-in-the-New-Space-Age-The-Orbital-Security-Dilemma/Townsend/p/book/9780367432072">shared commercial interests</a>. In this scenario, commercial entities act as intermediaries between states, uniting them behind specific commercial projects in space.</p>
<p>[<em><a href="https://memberservices.theconversation.com/newsletters?nl=science&source=inline-science-corona-important">Get The Conversation’s most important coronavirus headlines, weekly in a science newsletter</a></em>]</p>
<p>However, commercial enterprises are <a href="https://www.washingtonpost.com/politics/2022/01/11/companies-are-commercializing-outer-space-do-government-programs-still-matter/">unlikely to dictate future international cooperation in space</a>. According to current international space law, any company that operates in space does so <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/outerspacetreaty.html#:%7E:text=Article%20VIII,or%20on%20a%20celestial%20body">as an extension of</a> – and under the jurisdiction of – its home nation’s government.</p>
<p>The dominance of states over companies in space affairs has been starkly exemplified through the Ukraine crisis. As a result of state-imposed sanctions, many commercial space companies have <a href="https://www.reuters.com/business/aerospace-defense/uk-satellite-company-oneweb-suspends-baikonur-launches-2022-03-03/">stopped collaborating</a> with Russia.</p>
<p>Given the current legal framework, it seems most likely that states – not commercial entities – will continue to dictate the rules in space. </p>
<h2>Space blocs for collaboration or conflict</h2>
<p>I believe that going forward, state formations – such as space blocs – will serve as the major means through which states further their national interests in space and on the ground. There are many benefits when nations come together and form space blocs. Space is hard, so pooling resources, manpower and know-how makes sense. However, such a system also comes with inherent dangers.</p>
<p>History offers many examples showing that the more rigid alliances become, <a href="https://wcfia.harvard.edu/publications/understanding-global-conflict-and-cooperation-introduction-theory-and-history">the more likely</a> conflict is to ensue. The growing rigidity of two alliances – the Triple Entente and the Triple Alliance – at the end of 19th century is often cited as the <a href="https://wcfia.harvard.edu/publications/understanding-global-conflict-and-cooperation-introduction-theory-and-history">key trigger</a> of World War I.</p>
<p>A key lesson therein is that as long as existing space blocs remain flexible and open to all, cooperation will flourish and the world may yet avoid an open conflict in space. Maintaining the focus on scientific goals and exchanges between and within space blocs – while keeping political rivalries at bay – will help to ensure the future of international cooperation in space.</p><img src="https://counter.theconversation.com/content/180221/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Svetla Ben-Itzhak 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>In the past 10 years, international alliances on Earth have begun to expand into space. Nations with similar interests collaborate with one another while competing with other space blocs.Svetla Ben-Itzhak, Assistant Professor of Space and International Relations, Air UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1772632022-03-03T14:43:01Z2022-03-03T14:43:01ZHow satellites are helping us to understand deadly avalanches<figure><img src="https://images.theconversation.com/files/449801/original/file-20220303-10768-15ttk7c.jpg?ixlib=rb-1.1.0&rect=49%2C36%2C8153%2C3000&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/himalaya-panoramic-view-himalayas-mountain-mount-699679042">Daniel Prudek/Shutterstock</a></span></figcaption></figure><p>Just over a year ago, one of the most destructive <a href="https://theconversation.com/climate-change-as-mountain-regions-warm-hydroelectric-power-plants-may-be-vulnerable-162635">rock-ice avalanches in Indian Himalaya</a> hit a small township, tragically wiping out more than 200 lives, several bridges, roads and two hydroelectric power plants.</p>
<p>Known as the Chamoli disaster, it was unique in its magnitude. Despite consisting of <a href="https://www.science.org/doi/10.1126/science.abh4455">80% of rock and only 20% of ice</a>, the avalanche mass was able to travel around 13km downstream before it turned into a debris flow, causing a flash flood in the Rishiganga and Dhauliganga rivers.</p>
<p>The scale of the disaster attracted the attention of scientists around the world. In the past several months, more than ten research articles have been published covering <a href="https://www.tandfonline.com/doi/full/10.1080/19475705.2021.2023661">investigations</a> into possible causes and changes to the valley afterwards. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/DoWivEFpbsE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<h2>Remote sensing</h2>
<p>Given the lack of field measurements due to the remote extreme terrain of this region, all these published studies have extensively used Earth Observation (EO) data from <a href="https://www.americanscientist.org/article/fifty-years-of-earth-observation-satellites">remote sensing satellites</a>. Special cameras on EO satellites capture energy that is either emitted or reflected from the Earth’s surface or its atmosphere, so remote sensing helps monitor particular environments quickly and effectively. </p>
<p>Space agencies such as <a href="https://www.nasa.gov/about/index.html">NASA</a> and the <a href="https://www.esa.int/Newsroom/About_the_European_Space_Agency#:%7E:text=ESA%20%2F%20Newsroom-,The%20European%20Space%20Agency%20(ESA)%20is%20Europe's%20gateway%20to%20space,of%20Europe%20and%20the%20world.">European Space Agency</a> and companies such as <a href="https://www.planet.com/">Planet Labs</a> are providing free, medium-to-high resolution images of Earth, encouraging independent research and scientific investigations. In fact, Planet Lab’s PlanetScope satellites were able to capture the Chamoli disaster in <a href="https://www.planet.com/pulse/rapid-response-research-the-chamoli-landslide/">real-time</a>.</p>
<p>The increasing number and capabilities of these satellites are proving to be extremely useful in understanding high-mountain hazards. Online geo-visualisation platforms such as <a href="https://www.google.com/intl/en_uk/earth/versions/">Google Earth</a> are offering repeat high-resolution images, enabling quick and effective visual analysis. In our <a href="https://www.mdpi.com/2072-4292/14/4/949/htm">study</a>, we were able to simulate and reconstruct the Chamoli disaster and a previous ice avalanche at the same site thanks to the rich archive of remote sensing data.</p>
<h2>Avalanche hot spot</h2>
<p>Our research started with an interesting observation, also reported by <a href="https://www.science.org/doi/10.1126/science.abh4455">other studies</a>: the Chamoli disaster site is a hotspot for avalanches. Scanning through past satellite images from the last 20 years, we identified two ice avalanches and several snow avalanches in the same valley.</p>
<figure class="align-center ">
<img alt="A gif showing the height of debris that broke off a hanging glacier and fell down a mountain in India in 2016." src="https://images.theconversation.com/files/449752/original/file-20220303-15-111xd0w.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/449752/original/file-20220303-15-111xd0w.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=618&fit=crop&dpr=1 600w, https://images.theconversation.com/files/449752/original/file-20220303-15-111xd0w.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=618&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/449752/original/file-20220303-15-111xd0w.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=618&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/449752/original/file-20220303-15-111xd0w.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=776&fit=crop&dpr=1 754w, https://images.theconversation.com/files/449752/original/file-20220303-15-111xd0w.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=776&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/449752/original/file-20220303-15-111xd0w.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=776&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The 2016 avalanche that made the area more vulnerable to the event that followed in 2021, below.</span>
<span class="attribution"><span class="source">Anshuman Bhardwaj/University of Aberdeen</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Ice avalanches caused by breakage of a hanging glacier in early 2000 and again in September 2016 were massive, consisting of approximately 10 million m³ of glacial ice, filling around 3.5km of the valley floor with debris deposits that reached heights of up to 50m. However, because the Chamoli disaster occurred within 4.5 years of the September 2016 ice avalanche, it makes the whole scenario even more intriguing.</p>
<p>The 2021 disaster was caused by an avalanche which, although more than 2.5 times more voluminous than the 2016 event, was made of 80% of rocks contrary to the pure icy composition of 2016’s avalanche.</p>
<p>The sequence of these two massive and constituently different ice avalanches, originating from the same elevation and hitting the same valley within a period of five years, is unique. It offered us an unprecedented natural testbed to understand how frequent avalanches, with varying degree of ice content, can vary in terms of their run-out and destructive power.</p>
<figure class="align-center ">
<img alt="A gif showing the height of debris that broke off a hanging glacier and fell down a mountain in India in February 2021." src="https://images.theconversation.com/files/449628/original/file-20220302-17-9kljo3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/449628/original/file-20220302-17-9kljo3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=558&fit=crop&dpr=1 600w, https://images.theconversation.com/files/449628/original/file-20220302-17-9kljo3.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=558&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/449628/original/file-20220302-17-9kljo3.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=558&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/449628/original/file-20220302-17-9kljo3.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=702&fit=crop&dpr=1 754w, https://images.theconversation.com/files/449628/original/file-20220302-17-9kljo3.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=702&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/449628/original/file-20220302-17-9kljo3.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=702&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The 2021 Chamoli avalanche consisted of 80% rock and 20% ice, which made it all the more deadly.</span>
<span class="attribution"><span class="source">Anshuman Bhardwaj/University of Aberdeen</span></span>
</figcaption>
</figure>
<h2>Predicting the future</h2>
<p>Adopting an integrative approach, we studied both the pre-event and during-event flow characteristics of the 2016 and 2021 avalanches. We observed short-term and long-term changes in the rate of surface movement which reaches up to over around five times the normal values. </p>
<p>The estimation of surface movements has proven effective in observing the development and trajectory of ice avalanches in the past. In 1973, movements were measured for the <a href="https://doi.org/10.3189/S0022143000029592">first time</a> on an unstable hanging glacier in order to predict its collapse. The success of this field-based monitoring approach was demonstrated in 2014 by the <a href="https://tc.copernicus.org/articles/10/1191/2016/tc-10-1191-2016.html">accurate prediction</a> of a hanging glacier “break-off” from the south face of the Grandes Jorasses in Italy, 10 days before the avalanche happened.</p>
<p>But logistics issues in these high-mountain areas mean these kinds of field-based efforts are limited. Our observations, particularly for the 2016 avalanche, highlight that remote sensing movement estimations not only have larger coverage, but can also represent a timely, cost-effective and safer way to monitor hanging glaciers, and possibly even predict large and dangerous ice avalanches.</p>
<p>But there are uncertainties associated with remote sensing observations, and any possible future predictability certainly requires more research to identify statistically significant trends in surface movements.</p>
<p>Using a <a href="https://www.slf.ch/en/news/2018/04/new-thermomechanical-model-for-rockice-avalanches.html">thermomechanical model</a>, we simulated the September 2016 event and the maximum pressure exerted by this event on the valley. We discovered it was 6,000 kilopascal (a measurement of compressive strength) – big enough to make visible changes in the valley profile by adding erodible sediments, which could worsen any future event.</p>
<p>Seasonal snow avalanches also keep this part of the valley sufficiently lubricated. We then simulated the 2021 event under two scenarios: the first without specifying the erosion characteristics of the remaining avalanche deposits from the past, and the second with the inclusion of defined erosional zones.</p>
<p>The results indicate that the remaining valley deposits from past ice and snow avalanches likely aided the volume and flow of the 2021 rock-ice avalanche – which would explain its exceptional reach to the downstream population.</p>
<p>Although the past ice avalanches of 2000 and 2016 did not inflict any direct damage to life and property, they are recurring events in this valley. But it is difficult to predict their future impact in combination with other glacial hazards, such as happened in the Chamoli disaster.</p>
<p>As climate change accelerates globally, such life-threatening scenarios are developing in other mountain regions too, with greater frequency and uncertainty. With satellites providing frequently updating images, understanding any patterns in these high-mountain hazards could help save many lives and protect expensive infrastructure in future.</p><img src="https://counter.theconversation.com/content/177263/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>Remote sensing satellites provide the crucial data that helps scientists model disasters so that they can work on predicting avalanche patterns in future.Anshuman Bhardwaj, Senior Lecturer of Earth Observation and Planetary Sciences, University of AberdeenLydia Sam, Lecturer in Earth Observation & Planetary Science, University of AberdeenLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1778912022-02-25T13:46:03Z2022-02-25T13:46:03ZRussian invasion of Ukraine and resulting US sanctions threaten the future of the International Space Station<figure><img src="https://images.theconversation.com/files/448437/original/file-20220224-63392-1p400w1.jpg?ixlib=rb-1.1.0&rect=30%2C45%2C1701%2C1128&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The International Space Station is run collectively by the U.S., Russia, the European Space Agency, Japan and Canada.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/nasamarshall/3907196583/in/photolist-6Xgpqk-yHjaMW-NqxNon-QYAfVi-MCJ5Tj-LGPFNe-vGWF4r-PXaMxc-oN3xdH-MSPRQ2-oMroEb-MbfSPh-9bTgAP-ak8Nkt-eHSdwp-9pzSDn-QsVrt3-6Xsffx-MAv2L4-6UuDmQ-Pah2Lr-PcLPc9-bfqNSX-Rv7qri-QZW9op-aBP3J4-QjfUiS-RgvHvr-QPTBJs-zj5VZD-9e8hcg-Na7Ypm-KZKmEP-fWFARy-B8kHmM-QoZztJ-QRonqA-MMZDtA-P4SLt7-aqUi9F-2kAugx4-2mCoQsh-MVyhL3-2mU6HBN-amD2x7-LTnpKt-2kW4xoj-2n5118N-H9HKsz-2mGbPm8">NASA Marshall Spaceflight Center/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span></figcaption></figure><p>New U.S. sanctions on Russia <a href="https://spacenews.com/biden-sanctions-will-degrade-russian-space-program/">will encompass Russia’s space agency</a>, Roscosmos, according to a <a href="https://www.youtube.com/watch?v=R8jA2LyBBxY">speech U.S. President Joe Biden gave</a> on Feb. 24, 2022.</p>
<p>In response to these sanctions, the head of Roscosmos on the same day <a href="https://spacenews.com/biden-sanctions-will-degrade-russian-space-program/">posted a tweet saying</a>, among other things, “If you block cooperation with us, who will save the ISS from an uncontrolled deorbit and fall into the United States or Europe?”</p>
<p>The International Space Station has often stayed above the fray of geopolitics. That position is under threat.</p>
<p>Built and run by the U.S., Russia, Europe, Japan and Canada, the ISS has shown how countries can cooperate on major projects in space. The station has been continuously occupied for over 20 years and has <a href="https://www.nasa.gov/feature/visitors-to-the-station-by-country/">hosted more than 250 people</a> from 19 countries.</p>
<p><a href="https://scholar.google.com/citations?user=PxIOz7cAAAAJ&hl=en&oi=ao">As a space policy expert</a>, the ISS represents, to me, a high point of cooperation in space exploration. But for <a href="https://www.nasa.gov/mission_pages/station/expeditions/index.html">the current crew</a> of two Russians, four Americans and one German, things may be getting worrisome as tensions rise between the U.S. and Russia. </p>
<p>Several agreements and systems are in place to make sure that the space station can function smoothly while being run by five different space agencies. As of Feb. 24, there were no announcements of unusual actions aboard the station despite the ongoing Russian invasion of Ukraine. But the Russian government has brought the ISS into geopolitics before and is doing so again.</p>
<h2>Managing the ISS</h2>
<p>What came to be known as the International Space Station was first conceived on NASA drawing boards in the early 1980s. As costs rose past initial estimates, <a href="https://scholar.smu.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1524&context=jalc">NASA officials invited international partners</a> from the European Space Agency, Canada and Japan to join the project. </p>
<p>When the Soviet Union collapsed at the end of the Cold War in the early 1990s, the Russian space program <a href="https://www.thoughtco.com/soviet-space-program-history-4140631">found itself in dire straits</a>, suffering from lack of funding and an exodus of engineers and program officials. To take advantage of <a href="https://www.space.com/19650-mir-space-station.html">Russian expertise in space stations</a> and foster post-Cold War cooperation, the NASA administrator at the time, Dan Goldin, <a href="https://doi.org/10.1016/j.spacepol.2018.07.003">convinced the Clinton administration</a> to bring Russia into the program that was rechristened the International Space Station. </p>
<p>By 1998, just prior to the launch of the first modules, Russia, the U.S. and the other international partners of the ISS entered into <a href="https://www.nasa.gov/mission_pages/station/structure/elements/partners_agreement.html">memorandums of understanding</a> that spelled out how major decisions would be made and what kind of control each nation would have over various parts of the station.</p>
<p>The body that <a href="https://www.nasa.gov/mission_pages/station/structure/elements/nasa_rsa.html">governs the operation of the space station</a> is the Multilateral Coordination Board. This board has representatives from each of the space agencies involved in the ISS and is chaired by the U.S. The board operates by consensus in making decisions on things like a <a href="https://www.researchgate.net/publication/8677856_The_Code_of_conduct_for_International_Space_Station_crews">code of conduct for ISS crews</a>. </p>
<p>Even among international partners who want to work together, consensus is not always possible. If this happens, either the chair of the board can make decisions on how to move forward or the issue can be elevated to the NASA administrator and the head of the Russian space agency, Roscosmos.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing the different parts of the ISS." src="https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=391&fit=crop&dpr=1 600w, https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=391&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=391&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=492&fit=crop&dpr=1 754w, https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=492&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/448439/original/file-20220224-64024-f723h2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=492&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The International Space Station is built of many individual modules that are fully under the control of the countries or agencies that built them.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:ISS_configuration_2021-11_en.svg#/media/File:ISS_configuration_2021-11_en.svg">NASA / Colds7ream, Fritzbox, Johndrinkwater, Ras67, Chepry via Wikimedia Commons</a></span>
</figcaption>
</figure>
<h2>Territories in space</h2>
<p>While the overall operations of the station are run by the Multilateral Coordination Board, things are more complicated when it comes to the modules themselves. </p>
<p>The International Space Station is made of <a href="https://www.nasa.gov/mission_pages/station/structure/elements/space-station-assembly">16 different segments</a> constructed by different countries, including the U.S., Russia, Japan, Italy and the European Space Agency. Under the ISS agreements, each country maintains control over how its modules are used. This includes the Russian <a href="https://www.nasa.gov/mission_pages/station/structure/elements/zarya-cargo-module">Zarya</a>, which provides electricity and propulsion to the station, and <a href="https://www.nasa.gov/mission_pages/station/structure/elements/zvezda-service-module.html">Zvezda</a>, which provides all of the station’s life support systems like oxygen production and water recycling.</p>
<p>The result is that ISS modules are treated legally as if they are <a href="https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/International_Space_Station/International_Space_Station_legal_framework">territorial extensions</a> of their countries of origin. While all crew onboard can theoretically be in and use any of the modules, how they are used must be approved by each country.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A white Soyuz rocket lifting off from a launch pad." src="https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=980&fit=crop&dpr=1 600w, https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=980&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=980&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1232&fit=crop&dpr=1 754w, https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1232&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/448438/original/file-20220224-17-n5pr3e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1232&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">For nearly 10 years, the Russian Soyuz rocket was the only way for astronauts to get to the ISS.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Soyuz_TMA-13_Edit.jpg#/media/File:Soyuz_TMA-13_Edit.jpg">NASA/Bill Ingalls via WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>International tensions and the ISS</h2>
<p>While the ISS has functioned under this structure remarkably well since its launch more than 20 years ago, there have been some disputes. </p>
<p><a href="https://www.nytimes.com/2014/03/19/world/europe/ukraine.html">When Russian forces annexed</a> the Ukrainian territory of Crimea in 2014, the U.S. imposed economic sanctions on Russia. As a result, Russian officials <a href="https://www.vox.com/2014/5/13/5714650/russia-just-evicted-nasa-from-the-international-space-station">announced that they would no longer launch</a> U.S. astronauts to and from the space station beginning in 2020. Since NASA had retired the space shuttle in 2011, the U.S. was entirely dependent on Russian rockets to get astronauts to and from the ISS, and this threat could have meant the end of the American presence aboard the space station entirely.</p>
<p>While Russia did not follow through on its threat and continued to transport U.S. astronauts, the threat needed to be taken seriously. The situation today is quite different. The U.S. has been relying on private SpaceX rockets to transport astronauts to and from the ISS. This makes potential Russian threats to launch access less meaningful. </p>
<p>But the invasion of Ukraine does seem to have upped the intensity of geopolitical maneuvering involving the ISS. </p>
<p>The new U.S. sanctions are designed to “<a href="https://spacenews.com/biden-sanctions-will-degrade-russian-space-program/">degrade their aerospace industry, including their space program</a>.” The <a href="https://twitter.com/Rogozin/status/1496933548372209669?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1496933548372209669%7Ctwgr%5E%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fspacenews.com%2Fbiden-sanctions-will-degrade-russian-space-program%2F">tweet in response</a> from Dmitry Rogozin, the head of Roscosmos, “explained” that Russian modules are key to moving the station when it needs to dodge <a href="https://theconversation.com/why-space-debris-cleanup-might-be-a-national-security-threat-105816">space junk</a> or adjust its orbit. He went on to say that Russia could either <a href="https://www.msn.com/en-us/news/world/russian-space-agency-head-suggests-sanctions-may-lead-to-iss-plummeting/ar-AAUgEIH">refuse to move the station when needed or even crash it into the U.S., Europe, India or China</a>. </p>
<p>Though dramatic, this is likely an idle threat due to both political consequences and the practical difficulty of getting Russian cosmonauts off the ISS safely. But I am concerned about how the invasion will affect the remaining years of the space station.</p>
<p>In December 2021, the <a href="https://spacenews.com/other-iss-partners-start-planning-for-extension-to-2030/">U.S. announced its intention to</a> extend operation of ISS operations from its planned end date of 2024 to 2030. Most ISS partners expressed support for the plan, but Russia will also need to agree to keep the ISS operating beyond 2024. Without Russia’s support, the station – and all of its scientific and cooperative achievements – may face an early end.</p>
<p>The ISS has served as a prime example for how nations can cooperate with one another in an endeavor that has been relatively free from politics. Increasing tensions, threats and more aggressive Russian actions – including its <a href="https://theconversation.com/russian-anti-satellite-weapon-test-what-happened-and-what-are-the-risks-172016">recent test of anti-satellite weapons</a> – are straining the realities of international cooperation in space going forward.</p><img src="https://counter.theconversation.com/content/177891/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Wendy Whitman Cobb is affiliated with the US Air Force School of Advanced Air and Space Studies. Her views are her own and do not necessarily reflect the views of the Department of Defense or any of its components. </span></em></p>What happens to the International Space Station when tensions on Earth rise? A space policy expert explains how the ISS is run and how Russian aggression has threatened its operation in the past – and now.Wendy Whitman Cobb, Professor of Strategy and Security Studies, Air UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1681592021-10-04T11:40:54Z2021-10-04T11:40:54ZBepiColombo’s first close-up pictures of Mercury’s surface hint at answers to the planet’s secrets<figure><img src="https://images.theconversation.com/files/423350/original/file-20210927-15-1qyik7a.jpg?ixlib=rb-1.1.0&rect=5%2C5%2C3830%2C2151&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artist's impression of BepiColombo during a swing-by of Mercury</span> <span class="attribution"><span class="source">ESA/ATG medialab</span></span></figcaption></figure><p>The <a href="https://www.esa.int/Science_Exploration/Space_Science/BepiColombo/Mercury_ahead!">BepiColombo spacecraft</a> – a joint project by the European and Japanese space agencies – swung by its destination planet Mercury in the early hours of October 2 2021. Passing within just 200km of the surface of Mercury, it sent back some <a href="https://www.esa.int/Science_Exploration/Space_Science/BepiColombo/BepiColombo_s_first_views_of_Mercury">spectacular pictures</a>.</p>
<p>For those of us who have worked for a decade or more on this mission, there could hardly be a way better to celebrate what would have been the 101st birthday of the mission’s namesake, Italian mathematician and engineer Giuseppe Colombo. His groundbreaking work in this area earned him the title of the <a href="https://www.esa.int/About_Us/ESA_history/Giuseppe_Bepi_Colombo_Grandfather_of_the_fly-by">grandfather</a> of the planetary fly-by technique, now more often termed a “swing-by”.</p>
<p>BepiColombo’s cruise from Earth began in <a href="https://theconversation.com/europe-blasts-off-to-mercury-heres-the-rocket-science-104641">October 2018</a>, and its journey is far from over. It will travel twice around the sun in the time it takes Mercury to orbit the sun three times (around 264 days). This will allow it to rendezvous with the planet for another swing-by on June 23 2022. </p>
<p>After a total of six Mercury swing-bys, the cumulative effect of the planet’s gravity will reduce the spacecraft’s velocity to the point where it can fall into orbit with Mercury around the end of 2025.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The BepiColombo spacecraft showing where the external cameras are mounted" src="https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=215&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=215&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=215&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=270&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=270&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422196/original/file-20210920-22-14erckt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=270&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Left: the location of the three MCAMs on the Mercury Transfer Module, seen in an exploded view of the spacecraft stack. Right: artist’s impression of the stacked spacecraft.</span>
<span class="attribution"><span class="source">Left: Micro-Cameras & Space Exploration SA. Right: spacecraft: ESA/ATG medialab; Mercury: Nasa/JPL</span></span>
</figcaption>
</figure>
<p>BepiColombo is actually composed of two <a href="https://sci.esa.int/web/bepicolombo">connected</a> spacecraft and a propulsion unit. During its cruise through interplanetary space, the European orbiter (called the “<a href="https://www.cosmos.esa.int/web/bepicolombo/mpo">Mercury Planetary Orbiter</a>” or MPO) is attached on one side to the interplanetary propulsion unit (or “<a href="https://www.esa.int/Science_Exploration/Space_Science/BepiColombo/Mercury_Transfer_Module">Mercury Transfer Module</a>”). On the other, it carries a Japanese orbiter named Mio (or “<a href="https://www.isas.jaxa.jp/en/missions/spacecraft/current/mmo.html">Mercury Magnetospheric Orbiter</a>”), plus a sunshield to prevent Mio from overheating. </p>
<p>This stacked configuration obstructs the openings through which sophisticated visible, infrared and X-ray cameras inside MPO – capable of imaging and analysing Mercury’s surface in great detail – will operate once MPO finally becomes free-flying. In fact, most of BepiColombo’s science instruments will be wholly or partly inoperative until each orbiter is set free, around December 2025.</p>
<h2>Adding the cameras</h2>
<p>Until a relatively late stage in mission planning, it was accepted that BepiColombo would be “flying blind” during its whole cruise from Earth, including during swing-bys – meaning no images would be available until orbit around Mercury had been achieved. </p>
<p>But the level of public interest aroused in 2015 by by images of <a href="https://theconversation.com/rosetta-scientists-unveil-the-source-of-ice-and-dust-jets-on-comet-67p-48122">comet 67P</a> from the Rosetta mission led BepiColombo engineers Kelly Geelen and James Windsor to propose that low-cost lightweight cameras should be added to the spacecraft. </p>
<p>By the end of 2016, it was agreed that three small monitoring cameras – each only 6.5cm in length – would be mounted onto the craft. These would snap planetary pictures during swing-bys. </p>
<p>It was decided to place these cameras on the Mercury Transfer Module, where they would also be able to monitor the deployment of the solar panels that provide the spacecraft with power, the magnetometer boom used for measuring magnetic fields, and the communication antennae.</p>
<figure class="align-center ">
<img alt="One of the monitoring cameras as used on BepiColombo" src="https://images.theconversation.com/files/422419/original/file-20210921-17-fjmmav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/422419/original/file-20210921-17-fjmmav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=263&fit=crop&dpr=1 600w, https://images.theconversation.com/files/422419/original/file-20210921-17-fjmmav.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=263&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/422419/original/file-20210921-17-fjmmav.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=263&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/422419/original/file-20210921-17-fjmmav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=330&fit=crop&dpr=1 754w, https://images.theconversation.com/files/422419/original/file-20210921-17-fjmmav.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=330&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/422419/original/file-20210921-17-fjmmav.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=330&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Extremely small and light monitoring cameras carry out a range of functions on a spacecraft such as BepiColombo.</span>
<span class="attribution"><span class="source">Micro-Cameras & Space Exploration SA.</span></span>
</figcaption>
</figure>
<h2>What Bepi saw</h2>
<p>During BepiColombo’s first Mercury swing-by, the fields of view of monitoring cameras two and three tracked across the planet. Camera three showed us part of the southern hemisphere, beginning with a view of sunrise over <a href="https://messenger.jhuapl.edu/Explore/Science-Images-Database/gallery-image-238.html">Astrolabe Rupes</a> – a striking feature named after a French Antarctic exploration ship. </p>
<p>Astrolabe Rupes is a 250km long “<a href="http://lroc.sese.asu.edu/posts/374">lobate scarp</a>” – a long, curved structure marking where one part of the planet’s crust has been pushed over nearby terrain, due to the whole planet contracting as it slowly cooled. </p>
<p>There are some much smaller <a href="https://theconversation.com/the-moon-is-still-geologically-active-study-suggests-116768">equivalent features</a> on the Moon, but Mercury is the only nearby celestial body where lobate scarps are known to occur on such a large scale.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A geological feature of Mercury" src="https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424297/original/file-20211002-25-1lyhkp0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Astrolabe Rupes catches the light of the rising sun, captured at a range of 1183km. MPO’s transmitting antenna is brightly lit in the foregound, contributing to a ghosting effect in the middle of the image.</span>
<span class="attribution"><span class="source">ESA/BepiColombo/MTM, CC BY-SA 3.0 IGO</span></span>
</figcaption>
</figure>
<p>Four minutes later, the perspective had changed enough to reveal a wider area: including the lava-flooded, 251km-wide <a href="https://www.esa.int/ESA_Multimedia/Images/2021/10/A_taste_of_Mercury_geology_annotated">Haydn crater</a> and <a href="https://theconversation.com/mysterious-red-spots-on-mercury-get-names-but-what-are-they-95114">Pampu Facula</a>, one of many bright spots likely formed by explosive volcanic eruptions. Both of these features attest to Mercury’s long volcanic history, at its most active more than three billion years ago but probably persisting until around one billion years ago. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A wider-angle view of Mercury's surface" src="https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424298/original/file-20211002-25-1obbu0t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Astrolabe Rupes is still visible in this image taken at 2687km, allowing a wider area of the planet’s surface to be seen.</span>
<span class="attribution"><span class="source">https://www.esa.int/Science_Exploration/Space_Science/BepiColombo/BepiColombo_s_first_views_of_Mercury</span></span>
</figcaption>
</figure>
<p>Meanwhile, camera two focused on Mercury’s northern hemisphere, including the region surrounding <a href="https://www.nasa.gov/mission_pages/messenger/multimedia/messenger_orbit_image20111123_1.html">Calvino crater</a>: an important location for deciphering what lies in the layers of Mercury’s crust. </p>
<p>It also showed Lermontov crater: a region which appears bright because it is host to both <a href="https://news.ncsu.edu/2016/08/byrne-mercury/">volcanic deposits</a> and “hollows”, where a currently unknown <a href="https://www.smithsonianmag.com/smart-news/mercurys-messy-surface-hints-planet-was-once-habitable-180974501/">volatile ingredient</a> of the crust is being lost to space via a mysterious process.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Mercury's North hemisphere" src="https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424299/original/file-20211002-46781-ub8qnv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">At 2418km, Mercury’s North hemisphere is towards the lower left, and a brightly sunlit magnetometer boom is in the foreground.</span>
<span class="attribution"><span class="source">ESA/BepiColombo/MTM, CC BY-SA 3.0 IGO</span></span>
</figcaption>
</figure>
<p>Nasa’s <a href="https://solarsystem.nasa.gov/missions/messenger/in-depth/">MESSENGER</a> mission orbited Mercury between 2011 and 2015, revealing a <a href="https://theconversation.com/the-more-we-learn-about-mercury-the-weirder-it-seems-55972">perplexing planet</a>. We are still struggling to understand its composition, origin and history.</p>
<p>Why Mercury has features such as explosive <a href="https://mobile.arc.nasa.gov/public/iexplore/missions/pages/yss/may.html">volcanoes</a> and strange, unique <a href="https://www.planetary.org/articles/02171332-what-are-mercurys-hollows">hollows</a> on its surface is just one of the problems we hope further study will solve. Once in orbit, BepiColombo’s advanced payload of scientific instruments will help us understand more about how Mercury formed and what it’s made of.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-more-we-learn-about-mercury-the-weirder-it-seems-55972">The more we learn about Mercury, the weirder it seems</a>
</strong>
</em>
</p>
<hr>
<p>In the meantime, these extraordinary swing-by pictures at least remind us that we have a healthy spacecraft heading to an exciting destination.</p><img src="https://counter.theconversation.com/content/168159/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Rothery is Professor of Planetary Geosciences at the Open University. He is co-leader of the European Space Agency's Mercury Surface and Composition Working Group, and a Co-Investigator on MIXS (Mercury Imaging X-ray Spectrometer) that is now on its way to Mercury on board the European Space Agency's Mercury orbiter BepiColombo. He has received funding from the UK Space Agency and the Science & Technology Facilities Council for work related to Mercury and BepiColombo, and from the European Commission under its Horizon 2020 programme for work on planetary geological mapping (776276 Planmap). He is author of Planet Mercury - from Pale Pink Dot to Dynamic World (Springer, 2015), Moons: A Very Short Introduction (Oxford University Press, 2015) and Planets: A Very Short Introduction (Oxford University Press, 2010). He is Educator on the Open University's free learning Badged Open Course (BOC) on Moons and its equivalent FutureLearn Moons MOOC, and chair of the Open University's level 2 course on Planetary Science and the Search for Life.</span></em></p>What did Mercury look like as BepiColombo swung by?David Rothery, Professor of Planetary Geosciences, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1633332021-06-24T16:16:14Z2021-06-24T16:16:14ZWhy is there so little water left on Mars?<figure><img src="https://images.theconversation.com/files/408129/original/file-20210624-25-zq788o.jpg?ixlib=rb-1.1.0&rect=4%2C2%2C920%2C740&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Mars northern polar cap, photographed by the NASA Mars Reconnaissance Orbiter mission.</span> <span class="attribution"><a class="source" href="https://www.nasa.gov/images/content/458463main_pia13163.jpg">NASA/JPL-Caltech/MSSS</a></span></figcaption></figure><p>Mars is known for its thin atmosphere, where CO<sub>2</sub> dominates and provides most of the atmospheric mass and pressure. In fact, the pressure is similar to that in the Earth’s stratosphere, which is a layer of the atmosphere, at more than 30km above the surface.</p>
<p>But what about water? Water on Mars <a href="https://doi.org/10.1017/9781139060172.011">is currently found on the surface</a> as a layer of ice – several kilometres thick – at the north pole. It also appears as seasonal frost at the coldest times of the year, and in the atmosphere as vapour and ice. Nevertheless, the Martian atmosphere is extremely dry compared to Earth’s, with about 100 times less water. While precipitation on Earth results in water layers several centimetres thick, water that would precipitate on Mars would only form a thin film of less than a millimetre.</p>
<p><a href="https://www.nature.com/articles/s41550-021-01389-x">New data</a> now provides a better understanding of why there is (almost) no water left on Mars.</p>
<h2>Water escapes from the Martian atmosphere</h2>
<p>The evidence suggests that Mars was not always the cold, arid planet we observe today. There is plenty of evidence of water on Mars’ surface in the distant past – about four billion years ago. At that time, liquid water flowed in great streams and stagnated in the form of pools or lakes, such as in the Jezero crater explored by the Perseverance rover, in search of traces of past life.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/407950/original/file-20210623-13-11l6fkx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/407950/original/file-20210623-13-11l6fkx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407950/original/file-20210623-13-11l6fkx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407950/original/file-20210623-13-11l6fkx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407950/original/file-20210623-13-11l6fkx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407950/original/file-20210623-13-11l6fkx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407950/original/file-20210623-13-11l6fkx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Jezero Crater, where Perseverance landed in February 2021, was a lake in the distant past.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/image-feature/jezero-crater-was-a-lake-in-mars-ancient-past/">NASA/JPL-Caltech</a></span>
</figcaption>
</figure>
<p>For liquid water to circulate and reside on the surface long enough to leave these marks, there must have been a radically different climate than the one we see today. Mars, Earth and Venus probably formed from the gradual accumulation of the same basic materials, which means that they must have had great similarities early in their history. But while Earth and Venus have retained most of their thick atmosphere, Mars, because of its small size and low gravity, has lost most of its atmosphere.</p>
<p>It is indeed this <a href="https://doi.org/10.1016/j.icarus.2018.05.030">“loss of gas to space”</a> that helps explain the current tenuousness of Mars’ atmosphere. This loss occurs very high in the atmosphere, above 200km, where molecules have already broken down into atoms and where the lightest ones, such as hydrogen, can be torn away from the weak gravity of Mars. Exposed to the energetic particles of the solar wind, Mars’ exosphere (the upper layer of the atmosphere) has allowed the equivalent of hundreds of present-day atmospheres to be lost to space.</p>
<h2>New data</h2>
<p>New data from the ESA’s <a href="https://exploration.esa.int/web/mars/-/46475-trace-gas-orbiter">Trace Gas Orbiter mission</a>, published <a href="https://www.nature.com/articles/s41550-021-01389-x">in the journal Nature Astronomy</a>, has shed light on the subtle mechanisms behind the loss of water to space.</p>
<p>Martian water has a very specific chemical composition. There are different “isotopes” of water – in the semiheavy water HDO, a hydrogen atom can be replaced by an atom of deuterium (D). (This is twice as heavy as hydrogen because it has a particle called a neutron in addition to the proton in its nucleus.) Measurements stretching back to the 1980s reveal that water on Mars has a relative concentration of deuterium six times greater than that on Earth. This is interpreted as the result of the loss of hydrogen, gradually leaving behind the heavier isotopes.</p>
<p>By extrapolation, the initial amount of water on Mars must have been at least six times greater than it is now, equivalent to a liquid layer of about 100 metres thick covering the planet. This shows how crucial the semiheavy water ratio is to understand Mars’ youth and to shed light on the hypothesis that it once had a warm and wet climate, a prerequisite for habitability.</p>
<p>These results from the Trace Gas Orbiter tell us how water and semiheavy water in the lower atmosphere reach the upper atmosphere and break down into atoms that can escape to space. In particular, it tells us more about the intermediate processes by which hydrogen and deuterium enter the exosphere.</p>
<p>For the past 20 years, two theories have suggested that hydrogen and deuterium cannot reach the exosphere in the proportions they do in lower atmospheric water molecules. The intermediate processes that could enable it, however, are condensation (water vapour turning into liquid water), which forms Martian water ice clouds, and photolysis, which breaks up the water molecule and releases a hydrogen or deuterium atom under the action of UV light.</p>
<p>What <a href="https://www.nature.com/articles/s41550-021-01389-x">our recent study</a> reveals is that condensation actually plays a minor role in the deuterium content of the exosphere. Thanks to the Trace Gas Orbiter’s Atmospheric Chemistry Suite instrument and its simultaneous measurements of H<sub>2</sub>0 and HDO, we were able to show where the hydrogen and deuterium atoms come from. That’s particularly important given that it is at an altitude and time of year on Mars where condensation has no opportunity to interfere with photolysis.</p>
<p>It turns out that photolysis is the dominating process: it produces the bulk of the atoms and dictates the isotopic fractionation of the hydrogen atoms that escape from the Martian upper atmosphere.</p>
<p>This new understanding of the processes that lead to the loss of water to space is a key milestone in attempts to trace the history of water on Mars. Only the Trace Gas Orbiter satellite is able to reveal the joint concentrations of H<sub>2</sub>0 and HDO. But <a href="https://mars.nasa.gov/maven/">the NASA satellite MAVEN</a> is able to observe and characterise hydrogen and deuterium populations in the exosphere.</p>
<p>The concomitance of these two missions is bringing to life a new line of research. It may allow scientists to describe the complete path of water on Mars – from the lower atmosphere to the very upper atmosphere and into space. Only a detailed understanding of this pathway will allow scientists to develop reliable scenarios for the history of water over the last few billion years, and to corroborate the past habitability of Mars.</p><img src="https://counter.theconversation.com/content/163333/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Franck Montmessin received funding from the French Agence Nationale de la Recherche and from the Centre National d'Études Spatiales.</span></em></p>New results show why and how water is disappearing from Mars atmosphere.Franck Montmessin, Directeur de recherche CNRS au Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ) – Université Paris-Saclay Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1594862021-05-30T19:38:52Z2021-05-30T19:38:52ZDestination Moon: is it time for us to send astronauts back?<figure><img src="https://images.theconversation.com/files/396329/original/file-20210421-19-id3tx6.jpg?ixlib=rb-1.1.0&rect=23%2C596%2C3874%2C2641&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Eugene Cernan on the Moon, December 13, 1972, during the Apollo 17 mission, the last manned flight to the Earth's natural satellite.</span> <span class="attribution"><span class="source">NASA</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>The series <a href="http://www.collectspace.com/news/news-102819a-for-all-mankind-apple-tv.html"><em>For All Mankind</em></a> (2019) is a fictional alternate history that imagines a world where the Soviet Union was the first power to send an astronaut to the moon. From that starting point, the two rival superpowers compete to establish their own lunar station. </p>
<p>Just a few short years later, the scenario is no fantasy. Fifty years after the <a href="https://www.nasa.gov/mission_pages/apollo/missions/apollo11.html">Apollo 11 mission</a> in 2019 the United States announced its intention to return to the Moon in 2024. In light of the concept of <a href="https://www.researchgate.net/publication/337737874_Toward_a_definition_of_New_Space_The_entrepreneurial_perspective_New_Space_Vol_63_2018_pp_187-190">“New Space”</a>, this new ambition highlights a growing geostrategic competition, particularly given China’s precipitous rise.</p>
<h2>Artemis, one step ahead</h2>
<p>To succeed on this mission, NASA has promoted the Artemis program, a consortium led by the United States that brings together <a href="https://www.nasa.gov/press-release/nasa-international-partners-advance-cooperation-with-first-signings-of-artemis-accords/">eight other countries</a> – Australia, Canada, Italy, Japan, Luxembourg, Ukraine, the United Arab Emirates and the United Kingdom. NASA and Brazil signed a <a href="https://www.gov.br/aeb/pt-br/assuntos/noticias/brazil-becomes-the-tenth-nation-to-join-the-artemis-program">statement of intent</a> in December 2020 to join the program. Each participant will contribute to the completion of the mission with technical and scientific support.</p>
<p>NASA is also counting on the private sector, including the <a href="https://www.space.com/spacex-wins-nasa-artemis-moon-lander-contest">SpaceX Starship</a> (SN1), to fulfill the human landing system (HLS) program. The program will have three stages: </p>
<ul>
<li><p>Artemis I, an unmanned flight scheduled by the end of 2021.</p></li>
<li><p>Artemis II, a manned flight with the goal of positioning the spacecraft in orbit around the Moon in 2023.</p></li>
<li><p>Artemis III, which will launch the lunar lander with two astronauts in 2024.</p></li>
</ul>
<p>In Japan, the Toyota Group has partnered with the Japan Aerospace Exploration Agency (JAXA) to propose a <a href="https://www.toyota-europe.com/world-of-toyota/articles-news-events/2019/toyota-jaxa">pressurized lunar vehicle</a> that would participate in future missions of the international program.</p>
<p>China also has an ambitious program in the works – the January 2019 landing of the <a href="https://www.nationalgeographic.com/science/article/china-change-4-historic-landing-moon-far-side-explained">Chang'e-4 spacecraft on the far side of the Moon</a> demonstrates its spectacular progress. In the summer of 2020, the China National Space Administration (CNSA) reiterated the country’s intention to create an <a href="http://www.chinadaily.com.cn/a/202009/09/WS5f581650a310675eafc585c4.html">international lunar research station</a> (ILRS) as soon as 2036. Moscow signed a <a href="https://spacenews.com/china-russia-enter-mou-on-international-lunar-research-station/">memorandum of understanding</a> in March 2021 with China to create a lunar station, but no further details are known at this point.</p>
<p>India is another contender. While the country’s space program does not currently envision the construction of a lunar base, it is preparing astronauts for a <a href="https://economictimes.indiatimes.com/technology/isro-sets-up-a-team-to-study-technology/articleshow/73528155.cms">lunar mission</a>. However, critical failures such as the <a href="https://www.space.com/india-admits-moon-lander-crash.html">Chandrayaan-2 crash</a> have slowed down the program’s development. Along with the <a href="http://www.unoosa.org/documents/pdf/copuos/stsc/2019/tech-47E.pdf">Gaganyaan program</a>, the Indian Space Research Organization (ISRO) planned to send a manned flight to the Moon, but it will not occur before the next decade.</p>
<h2>Settling on the Moon, for what purpose?</h2>
<p>Some consider the Moon as a necessary step before a manned mission to Mars, serving as a <a href="https://www.nbcnews.com/id/wbna26408095">training ground</a> for astronauts and forming the basis for a long-term human presence. However, the differences between their respective environments limits the validity of this hypothesis: Mars has an atmosphere that changes the <a href="https://www.theatlantic.com/science/archive/2020/02/nasa-moon-mars-artemis/606499/">access conditions</a>. For the time being, these projects remain in the realm of wishful thinking.</p>
<p>Although no one really knows the possibility and profitability of mining activities on the Moon, groups such as the <a href="https://www.planetary.org/">Planetary Society</a> argue that there are significant resources that could favor such an enterprise.</p>
<p>In recent years, discoveries have indicated <a href="https://www.npr.org/2020/10/26/927869069/water-on-the-moon-nasa-confirms-water-molecules-on-our-neighbors-sunny-surface?t=1619185737268">significant water-ice deposits</a> at the poles of the Moon. In a multitude of microcraters, 60% of the deposits would be set in the South Pole as <a href="https://www.nature.com/articles/s41550-020-1198-9">recent studies</a> suggest. Although no one has ventured to attempt a complete estimation, some research indicates that a significant volume of water is present – ranging from <a href="https://www.airspacemag.com/daily-planet/how-much-water-moon-180967751/">100 million to 1 billion tons for each polar area</a>. NASA’s interest in establishing a lunar station in this region is linked to the possibility of extracting water, a critical resource for sustainable human presence. However, the determination of water-ice <a href="https://www.scientificamerican.com/article/water-found-in-sunlight-and-shadow-on-the-moon/">morphology, concentration, distribution and abundance</a> remains essential, because the energy cost of its extraction depends on its nature. These data will determine the ability to execute any plan to exploit water-ice on the lunar surface.</p>
<p>The lunar soil could also conceal important reserves of <a href="http://www.esa.int/Enabling_Support/Preparing_for_the_Future/Space_for_Earth/Energy/Helium-3_mining_on_the_lunar_surface">helium-3</a>, whose volume would represent nearly 2.5 million tons according to <a href="https://www.lpi.usra.edu/meetings/lpsc2007/pdf/2175.pdf">Russian researchers</a>. Rare on Earth, this non-radioactive isotope could potentially serve as fuel for <a href="https://www.science.org.au/curious/space-time/mining-moon">nuclear fusion</a> reactors. But such reactors do not yet exist, and few people dare to make predictions about when they will be built. Very hypothetical to date, the use of helium-3 in the long term would require the design of a cost-effective extraction method with adequate infrastructure and the ability to transport it to Earth.</p>
<p>Furthermore, mining raises major legal issues as the United States has yet to sign the 1979 <a href="https://treaties.un.org/doc/Treaties/1984/07/19840711%2001-51%20AM/Ch_XXIV_02.pdf">Moon Treaty</a> along with China and Russia. On April 6, 2020, then-president Donald Trump issued an <a href="https://www.whitehouse.gov/presidential-actions/executive-order-encouraging-international-support-recovery-use-space-resources/">executive order</a> stating that the United States did not consider outer space to be part of global commons. In his first 100 days in office, President Joe Biden signed more than <a href="https://edition.cnn.com/interactive/2021/politics/biden-executive-orders/">60 executive orders</a>, but had not yet indicated if there would be a change in the US’ position on space resources. </p>
<p>Finally, NASA has unveiled the <a href="https://gcn.com/articles/2020/10/20/lunanet.aspx">LunaNet</a> architecture in its <a href="https://www.nasa.gov/sites/default/files/atoms/files/artemis_plan-20200921.pdf">Artemis program</a>. This device would facilitate the transfer of data between the Earth and the Moon, allowing astronauts to be alerted in real time when solar flares threaten space-based weather instruments. Complemented by positioning and navigation services, this architecture would secure human activities on the Moon.</p>
<h2>Limits and challenges</h2>
<p>Returning to the Moon implies significant budgetary efforts, even as the consequences of the Covid-19 pandemic have hit world economies hard. NASA’s 2021-2025 budget for the Artemis program is assured until 2024, set at <a href="https://phys.org/news/2020-09-nasa-moon-billion.html">$28 billion</a>, including $16 billion dedicated to the lunar lander. As yet the <a href="https://spacenews.com/biden-administration-proposes-24-5-billion-budget-for-nasa-in-2022/">Biden administration</a> has not stated that it will increase spending to enable humans to return to the lunar surface, and it could be delayed until <a href="https://theconversation.com/artemis-how-ever-changing-us-space-policy-may-push-back-the-next-moon-landing-155981">after 2024</a>.</p>
<p>The political context of the current Moon project differs from that of the Apollo program in the 1960s. At that time, the United States wanted to assert its superpower status, and the program had bipartisan support from the start. The current NASA program has the support of Congress, but budget negotiations are always troubled in the United States, particularly with the current partisan divisions. While the Democratic party control the House and Senate, the margin is exceedingly thin, particularly in the Senate. Therefore, NASA’s program needs lasting political support to be successful.</p>
<p>Given the financial uncertainties, technological hurdles, and logistical obstacles, a successful implementation of the US space program faces a wide range of challenges. In the context of the Earth’s environmental crisis, therein lies a question: will this return to the Moon be sustainable or will it just be a last-ditch effort?</p><img src="https://counter.theconversation.com/content/159486/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Florian Vidal works for the French Institute of International Relations (IFRI).</span></em></p><p class="fine-print"><em><span>José Halloy ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'a déclaré aucune autre affiliation que son organisme de recherche.</span></em></p>Several current programs aim at sending humans back to the Moon. What would be the purpose, and what are the real prospects?Florian Vidal, Associate Fellow, Université Paris CitéJosé Halloy, Professeur de physique - Physics professor, Université Paris CitéLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1578262021-04-11T16:54:32Z2021-04-11T16:54:32ZHow we mapped billions of trees in West Africa using satellites, supercomputers and AI<figure><img src="https://images.theconversation.com/files/391657/original/file-20210325-23-vh42gj.JPG?ixlib=rb-1.1.0&rect=12%2C18%2C4007%2C2661&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Modern computing allows to spot isolated trees and shrubs in semi-arid areas, facilitating research on the evolution of vegetation cover.</span> <span class="attribution"><span class="source">Martin Brandt</span>, <span class="license">Author provided</span></span></figcaption></figure><p>The possibility that vegetation cover in semi-arid and arid areas was retreating has long been an issue of international concern. In the 1930s it was first theorized that the Sahara was expanding and woody vegetation was on the retreat. In the 1970s, spurred by the <a href="https://www.gfdl.noaa.gov/sahel-drought/">“Sahel drought”</a>, focus was on the threat of “desertification”, caused by human overuse and/or climate change. In recent decades, the potential impact of climate change on the vegetation has been the main concern, along with the feedback of vegetation on the climate, associated with the role of the vegetation in the global carbon cycle.</p>
<p>Using high-resolution satellite data and machine-learning techniques at supercomputing facilities, we have now been able to map billions of individual trees and shrubs in West Africa. The goal is to better understand the real state of vegetation coverage and evolution in arid and semi-arid areas.</p>
<h2>Finding a shrub in the desert – from space</h2>
<p>Since the 1970s, satellite data have been used extensively to map and monitor vegetation in semi-arid areas worldwide. Images are available in “high” spatial resolution (with NASA’s satellites <a href="https://landsat.gsfc.nasa.gov/multispectral-scanner-system">Landsat MSS</a> and <a href="https://www.usgs.gov/centers/eros/science/usgs-eros-archive-landsat-archives-landsat-4-5-thematic-mapper-tm-level-1-data">TM</a>, and ESA’s satellites <a href="https://earth.esa.int/eogateway/missions/spot">Spot</a> and <a href="https://sentinels.copernicus.eu/web/sentinel/home">Sentinel</a>) and “medium or low” spatial resolution (<a href="https://earth.esa.int/eogateway/missions/noaa">NOAA AVHRR</a> and <a href="https://modis.gsfc.nasa.gov/about/">MODIS</a>).</p>
<p>To accurately analyse vegetation cover at continental or global scale, it is necessary to use the highest-resolution images available – with a resolution of 1 metre or less – and up until now the costs of acquiring and analysing the data have been prohibitive. Consequently, most studies have relied on moderate- to low-resolution data. This has not allowed for the identification of individual trees, and therefore these studies only yield aggregate estimates of vegetation cover and productivity, mixing herbaceous and woody vegetation.</p>
<p>In a new study covering a large part of the semi-arid Sahara-Sahel-Sudanian zone of West Africa, <a href="https://www.nature.com/articles/s41586-020-2824-5">published in <em>Nature</em></a> in October 2020, an international group of researchers was able to overcome these limitations. By combining an immense amount of high-resolution satellite data, advanced computing capacities, machine-learning techniques and extensive field data gathered over decades, we were able to identify individual trees and shrubs with a crown area of more than 3 m<sup>2</sup> with great accuracy. The result is a database of 1.8 billion trees in the region studied, available to all interested.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/391659/original/file-20210325-21-1nbg76x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/391659/original/file-20210325-21-1nbg76x.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=556&fit=crop&dpr=1 600w, https://images.theconversation.com/files/391659/original/file-20210325-21-1nbg76x.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=556&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/391659/original/file-20210325-21-1nbg76x.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=556&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/391659/original/file-20210325-21-1nbg76x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=699&fit=crop&dpr=1 754w, https://images.theconversation.com/files/391659/original/file-20210325-21-1nbg76x.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=699&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/391659/original/file-20210325-21-1nbg76x.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=699&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Supercomputing, machine learning, satellite data and field assessments allow to map billions of individual trees in West Africa.</span>
<span class="attribution"><span class="source">Martin Brandt</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Presently, this work is expanded to cover the semi-arid belt south of the Sahara across the African continent to the Red Sea. The current count of trees is 13 billion, and further refinements of the methodology are being made. It is expected that the geographical coverage will be widened, first to the rest of the semi-arid zones of Africa and then to other continents.</p>
<p>To cover Africa’s entire Sahelian zone, from the Atlantic to the Red Sea, we used approximately 100,000 satellite images – for a total data volume of hundreds of terabytes. Using NASA and <a href="https://en.wikipedia.org/wiki/Blue_Waters">Blue Waters</a> supercomputers, the images were stitched together to create a continuous mosaic. The trees were then identified using <a href="https://theconversation.com/deep-learning-and-neural-networks-77259">deep learning</a>, an artificial-intelligence technique in which the computer is trained to recognize individual trees. During the training, tens of thousands of trees were “shown” to the computer by an operator, using field knowledge in combination with image-interpretation skills. Subsequently, the results of the machine-based identification were checked. Overall, the accuracy has proven to be highly correlated with field measurements.</p>
<h2>Unexpected information on individual trees</h2>
<p>Our database of trees and shrubs contains information on each tree, its exact location (typically with an uncertainty of few meters), its crown size, the date of acquisition of the satellite image in which it was identified, and its estimated above-ground woody mass and carbon content. In the future, other information, e.g. its height and phenological characteristics may be added.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/391660/original/file-20210325-21-rsnscr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/391660/original/file-20210325-21-rsnscr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/391660/original/file-20210325-21-rsnscr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/391660/original/file-20210325-21-rsnscr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/391660/original/file-20210325-21-rsnscr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/391660/original/file-20210325-21-rsnscr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/391660/original/file-20210325-21-rsnscr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The relationship between humans and trees cannot always be related with losses in tree cover, as people in the semi-arid Sahel safeguard and promote trees within settlements and farmlands.</span>
<span class="attribution"><span class="source">Martin Brandt</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Already at this early stage of the project, important implications are evident. In the West-African study we found many more trees than we would have expected. Other data-sources actually report that trees are virtually absent in the Sahara and North-Sahelian zone, yet we found hundreds of millions of trees. The carbon stock associated with these trees is larger – and more stable – than carbon stocks in the herbaceous vegetation. Moreover, we found that trees in farmlands are generally larger than in pristine savannas, and the overall tree cover in populated and managed places is high. This exemplifies that high density of human population cannot always be related to losses in tree cover, as people in the semi-arid Sahel safeguard and promote trees within settlements and farmlands.</p>
<h2>What will the database be used for?</h2>
<p>This database is expected to be useful for a range of different purposes. In particular, it will constitute a baseline, allowing for future studies of the temporal evolution of woody vegetation at large scale, possibly even at a continental or global scale.</p>
<p>The database will allow analysis of which factors control the occurence of trees in drylands, for example human pressure, or environmental factors such as rainfall, soils or geomorphology. The information will feed into the modeling of ecosystems and “full Earth System”, since trees are of great significance in the interaction between the atmosphere and the land surface, controlling both carbon exchange, evapotranspiration and aerodynamic roughness.</p>
<p>Finally, the information could be used to inform and support environmental policies at national and international levels.</p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=121&fit=crop&dpr=1 600w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=121&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=121&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=152&fit=crop&dpr=1 754w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=152&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=152&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em>Created in 2007 to help accelerate and share scientific knowledge on key societal issues, the Axa Research Fund has been supporting nearly 600 projects around the world conducted by researchers from 54 countries. To learn more, visit the site of the <a href="https://www.axa-research.org/en/">Axa Research Fund</a>.</em></p><img src="https://counter.theconversation.com/content/157826/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Martin Brandt a reçu des financements de AXA post doctoral research fund. </span></em></p><p class="fine-print"><em><span>Kjeld Rasmussen ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'a déclaré aucune autre affiliation que son organisme de recherche.</span></em></p>Advanced techniques allowed our research team to build an open database of billions of individual trees and challenge some common perceptions about vegetation in arid and semi-arid zones.Martin Brandt, Assistant professor of geography, University of CopenhagenKjeld Rasmussen, Associate professor emeritus, University of CopenhagenLicensed as Creative Commons – attribution, no derivatives.