tag:theconversation.com,2011:/au/topics/rockets-22372/articlesRockets – The Conversation2023-10-13T18:24:51Ztag:theconversation.com,2011:article/2155842023-10-13T18:24:51Z2023-10-13T18:24:51ZIsrael seems poised for a massive invasion of Gaza rather than prolonged attrition<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/israel-seems-poised-for-a-massive-invasion-of-gaza-rather-than-prolonged-attrition" width="100%" height="400"></iframe>
<p>In the days since the Oct. 7 <a href="https://theconversation.com/the-unprecedented-attack-against-israel-by-hamas-included-precise-armed-drones-and-thousands-of-rockets-215241">surprise attack by Hamas</a>, Israel has counted its dead and secured its borders. The country now faces a grim choice. </p>
<p>Will it continue trading air strikes and rocket fire with Hamas militants for a prolonged period? Or will it launch a ground invasion of Gaza that triggers more casualties among Israeli soldiers and Palestinian civilians while risking a two-front war?</p>
<p>The conflict so far already has been bloody. <a href="https://www.timesofisrael.com/israel-girds-for-long-war-as-death-toll-from-hamas-terror-onslaught-passes-1300/">Israel reports 1,300 dead and 3,300 injured</a>, with perhaps <a href="https://www.timesofisrael.com/idf-warns-civilians-to-leave-northern-gaza-as-ground-invasion-looms/">150 more held hostage</a> in Gaza. Israeli officials also say <a href="https://www.timesofisrael.com/idf-warns-civilians-to-leave-northern-gaza-as-ground-invasion-looms/">1,500 Hamas militants</a> who entered Israel have been killed.</p>
<p>Gaza similarly reports <a href="https://www.aljazeera.com/news/2023/10/13/israel-hamas-war-list-of-key-events-day-7">6,600 injured and 1,500 dead</a>, enough to <a href="https://apnews.com/article/gaza-israel-palestinians-war-hamas-militants-civilians-casualites-8469bbcb566446d78f368bf2a1b49d88">overflow its morgues</a>.</p>
<p>Israel has now secured its border against further Hamas attacks on land. But the rockets keep flying overhead.</p>
<h2>Sustained rocketry</h2>
<p>Israel has counted <a href="https://twitter.com/IDF/status/1712755037259071505">6,000-plus incoming rockets so far</a>. After the first day’s 2,500-rocket barrage, it’s now about 700 per day. Given their estimated stockpiles of <a href="https://www.jpost.com/arab-israeli-conflict/what-do-hamas-and-pij-have-in-their-rocket-arsenals-analysis-667856">between 14,000</a> and <a href="https://www.iiss.org/online-analysis/online-analysis/2023/10/Hamas-attack-and-Israeli-military-options/">30,000 rockets</a>, Hamas militants could sustain such rates for many weeks.</p>
<p>The current rocket total has already surpassed the 4,380 reported during the <a href="https://www.cfr.org/global-conflict-tracker/conflict/israeli-palestinian-conflict">Israel-Gaza conflict in 2021</a>. Similarly, the current 700-rocket daily rate easily beats the 434 average of that 2021 conflict.</p>
<p>Israel’s <a href="https://theconversation.com/as-missiles-fly-a-look-at-israels-iron-dome-interceptor-94959">Iron Dome rocket interceptor systems</a> have consequently been busy. They <a href="https://mwi.westpoint.edu/what-happened-to-iron-dome-a-lesson-on-the-limits-of-technology-at-war/">might even have been overwhelmed</a> <a href="https://doi.org/10.1287/opre.2014.1309">on the first day.</a></p>
<p>The interceptor systems have clearly expended ample ammunition. I estimate they’ve launched roughly 2,300 interceptor missiles so far. <a href="https://doi.org/10.1093/jogss/ogx028">Assuming costs</a> of about US$100,000 dollars each, that’s US$230 million spent in six days.</p>
<p>The country’s interceptor stockpile is presumably running low. But Israel will likely receive more interceptor missiles via <a href="https://www.timesofisrael.com/liveblog_entry/first-us-transport-plane-with-advanced-ammunition-lands-in-israel/">ammunition resupply flights from the United States</a> that have already begun.</p>
<p>Despite most rockets reportedly being intercepted or landing in open fields, we know <a href="https://www.jpost.com/breaking-news/article-767695">some did not</a>. Based on past conflicts, I suspect at least 120 rockets have hit Israeli communities. That implies dozens of civilian deaths, as well as more injuries and much damage.</p>
<p>And each day the barrage continues, Israel suffers perhaps 10 more rocket hits and consumes another US$26 million of interceptors.</p>
<p>The rocketry hurts Israel’s economy too. Businesses lose productivity whenever employees must take shelter. And tourists won’t visit while <a href="https://twitter.com/manniefabian/status/1711313332068630896">rockets are falling near airports</a>.</p>
<p>Meanwhile, Israeli warplanes have been pounding Gaza.</p>
<h2>Airstrikes and mobilization</h2>
<p>They’ve so far dropped <a href="https://www.france24.com/en/middle-east/20231012-gaza-braces-for-ground-offensive-but-can-israel-achieve-its-objectives">4,000 tonnes of explosives</a> on Gaza.</p>
<p>But <a href="https://doi.org/10.1093/jogss/ogx028">my research indicates</a> that airstrikes didn’t slow the rocket fire during previous Gaza-Israel conflicts. Only ground assaults did that. </p>
<p>Warplanes also typically run out of worthwhile targets after about a week. And they’re more likely <a href="https://www.timesofisrael.com/liveblog_entry/hamas-claims-13-hostages-killed-in-airstrikes-including-foreigners/">to kill hostages</a> than to free them.</p>
<p>That’s partly why ceasefires took effect after <a href="https://www.cnn.com/2012/11/22/world/meast/gaza-israel-strike/index.html">eight days of fighting in 2012</a> and 10 days in 2021. And why Israel invaded Gaza on Day 8 of the conflict in 2009 and Day 11 in 2014.</p>
<p>(Oct. 14 will ominously mark Day 8 of this conflict. The clock is ticking.)</p>
<p>Meanwhile, Israel has mobilized <a href="https://www.timesofisrael.com/israel-girds-for-long-war-as-death-toll-from-hamas-terror-onslaught-passes-1300/">360,000 reservists</a>, giving it <a href="https://www.aljazeera.com/news/2023/10/12/what-will-israel-do-with-all-its-mobilised-soldiers">half a million soldiers</a> ready for action.</p>
<p>That’s expensive. The military must pay those extra people, while their normal civilian employers must go without them.</p>
<p>Altogether, the current fighting’s <a href="https://en.globes.co.il/en/article-economic-slowdown-looks-inevitable-for-israel-1001459931">direct and indirect expenses could cost Israel</a> at least $7 billion, or 1.5 per cent of its annual economic output. That’s assuming it doesn’t escalate.</p>
<h2>A northern front</h2>
<p>One place fighting could escalate is Israel’s northern border. In recent days, <a href="https://www.timesofisrael.com/idf-says-soldier-killed-in-hezbollah-anti-tank-cross-border-missile-attack/">Hezbollah and Palestinian Islamic jihad</a> militants in Lebanon and Syria have repeatedly fired at Israeli forces. Combatants on each side have been killed.</p>
<p>These attacks were small. But they force Israel to deploy some military units there instead of near Gaza. That includes at least one Iron Dome system.</p>
<p>The attacks also signal that Hezbollah could join the war if Israel invades Gaza. That group has far more soldiers than Hamas does. And its arsenal reportedly contains <a href="https://www.jpost.com/israel-news/article-742498">between 100,000</a> and <a href="https://missilethreat.csis.org/country/hezbollahs-rocket-arsenal/">130,000 rockets</a>, including some guided missiles.</p>
<p>So, what happens next?</p>
<h2>Decision time</h2>
<p>That largely depends on the Israeli government.</p>
<p>Its current situation is painful. The daily rocket salvos harm civilians in Israel, while the airstrikes hurt civilians in Gaza. And the Israeli economy bleeds cash every day the fighting continues.</p>
<p>Meanwhile, Israel’s air force has likely done all it can against Hamas. And the mobilized army is far too large for anything short of a Gaza invasion. The government surely feels pressured to “do something.”</p>
<p>An invasion seems imminent. Israel has <a href="https://www.timesofisrael.com/idf-warns-civilians-to-leave-northern-gaza-as-ground-invasion-looms/">told civilians in northern Gaza to flee somehow to the south</a> as Israeli forces move in, presumably to give their soldiers clearer fields of fire.</p>
<p>We might still hope a ceasefire will somehow be brokered. But it appears Israel is about to launch a bloody ground campaign.</p><img src="https://counter.theconversation.com/content/215584/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael J. Armstrong 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>It will be painful if Israel and Hamas militants continue to exchange rocket fire and airstrikes. But invading Gaza would increase the devastation even further.Michael J. Armstrong, Associate Professor, Operations Research, Brock UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2152412023-10-09T00:35:35Z2023-10-09T00:35:35ZThe unprecedented attack against Israel by Hamas included precise armed drones and thousands of rockets<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/the-unprecedented-attack-against-israel-by-hamas-included-precise-armed-drones-and-thousands-of-rockets" width="100%" height="400"></iframe>
<p>Last Friday, Israeli newspapers were filled with stories about the 50th anniversary of the Yom Kippur War, also called the October War. In 1973, the country had nearly been defeated by co-ordinated surprise attacks from its Arab neighbors. Never again, people thought.</p>
<p>So, Israelis were especially shocked to be awakened Saturday morning by rocket barrages and gunfire in the streets. Hamas militants from Gaza had launched a smaller but equally <a href="https://www.jpost.com/israel-news/article-765254">co-ordinated surprise attack</a>. It came by land, air <a href="https://www.timesofisrael.com/navy-says-it-killed-dozens-of-terrorists-attempting-to-infiltrate-from-sea/">and sea</a>.</p>
<p>The fighting <a href="https://www.aljazeera.com/news/2023/10/7/what-happened-in-israel-a-breakdown-of-how-the-hamas-attack-unfolded">began around 6:30 that morning</a>, when Hamas started firing rockets. But unlike many previous conflicts, this time it also attacked on the ground.</p>
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Read more:
<a href="https://theconversation.com/gazas-enhanced-rocket-technology-challenges-israels-defences-160853">Gaza's enhanced rocket technology challenges Israel's defences</a>
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<h2>Gunfights and airstrikes</h2>
<p>While the rocketry was still underway, Hamas blasted numerous holes in the security fences between Israel and Gaza. That let hundreds of armed militants pour across the border and quickly spread out across southern Israel.</p>
<p>These forces were small by military standards, but quickly overwhelmed the local border guards and police forces. The militants overran an army base, captured a police station and attacked several dozen communities.</p>
<p>The results were bloody. By Sunday, Israel had reported more than <a href="https://www.timesofisrael.com/death-toll-from-hamas-onslaught-passes-600-over-100-kidnapped-as-israel-strikes-gaza/">700 deaths and 2,200 injuries</a>, mostly civilians. Another 100 people were taken back to Gaza as hostages. Some of the victims were reportedly citizens of other countries, including Germany, Thailand, <a href="https://www.ctvnews.ca/canada/global-affairs-says-it-is-aware-of-reports-of-canadian-killed-amid-attack-on-israel-1.6594141">Canada</a> and the United States.</p>
<p>Israel’s army seemed largely absent from these initial fights. But its air force started bombing Gaza within hours, in Operation “Swords of Iron.” A day after the conflict started, the Palestinians reported <a href="https://www.aljazeera.com/gallery/2023/10/8/intense-battles-as-israel-declares-state-of-war">370 deaths and thousands of injuries</a> from the airstrikes.</p>
<p>The bloody ground attacks shocked Israel. But there were also surprises overhead.</p>
<h2>Massed rockets</h2>
<p>Militants in Gaza have been firing rockets toward Israel every year since 2005. I’ve <a href="https://brocku.ca/goodman/faculty-research/faculty-directory/michael-armstrong/">researched rocket defences and missile combat</a> for years, but the intensity of the Hamas attack this time was astounding. Israel counted more than 2,200 incoming rockets on Saturday morning alone; the total exceeded 2,500 by the day’s end.</p>
<p>That’s nearly quadruple the previous single-day record of 670 rockets. That was the number fired during the most intense day of <a href="https://theconversation.com/gazas-enhanced-rocket-technology-challenges-israels-defences-160853">2021’s Guardian of the Walls</a> operation.</p>
<p>The barrage wasn’t restricted to border areas. It reached across southern and central Israel, including the suburbs of Tel Aviv. A hospital and several other buildings were hit. And about a dozen people died, including <a href="https://www.timesofisrael.com/always-the-first-to-defend-the-israelis-slain-in-hamass-surprise-onslaught/">several at a Bedouin village</a> that had no defences.</p>
<p>The toll was relatively low partly because the rockets are inaccurate: most land in empty fields. And <a href="https://theconversation.com/as-missiles-fly-a-look-at-israels-iron-dome-interceptor-94959">Iron Dome interceptor systems</a> typically shoot down most of the rest. Failing that, many homes and communities have <a href="https://theconversation.com/israeli-rocket-experience-shows-bomb-shelters-matter-as-much-as-interceptors-96402">bomb shelters</a> where civilians can take cover.</p>
<p>Because the Iron Dome systems are so effective, they would be valuable for Hamas to destroy. But <a href="https://doi.org/10.1287/opre.2014.1309">rockets are too inaccurate</a> to hit such small targets.</p>
<p>However, if the militants roaming southern Israel on Saturday had found a system deployed there, they could easily have destroyed it. For example, there is often a system stationed near Sderot, one of the towns that was attacked.</p>
<p>There is another way to destroy small, high value targets: attack them with drones.</p>
<h2>Drones in Israel and Ukraine</h2>
<p>This seems to be the first conflict where Hamas has successfully used armed drones. Some are quadcopters that operators fly via remote control. They can precisely drop explosives onto small targets — like an Iron Dome system. Videos online show them attacking people, a watchtower and <a href="https://twitter.com/visegrad24/status/1710725094723469428">a tank</a>.</p>
<p>Ukraine has effectively used similar quadcopters against Russian military targets. They sometimes drop explosives right down an armoured vehicle’s open hatch.</p>
<p>Other Gazan drones resemble toy airplanes. They can fly considerable distances and then explode wherever they land.</p>
<p>Those drones are much like the ones Russia uses to attack Ukrainian cities. And both the Gazan and Russian drones resemble those made by Iran. That might not be co-incidental. <a href="https://theconversation.com/iran-flexes-its-missile-muscle-with-terrible-consequences-129669">Iran</a> is known to have supported Gaza militants in the past. And it has admitted selling some drones to Russia.</p>
<p>There’s another interesting connection between the Ukrainian and Israeli conflicts. Israel has provided humanitarian aid to Ukraine, but no weapons. Most notably, it has refused <a href="https://theconversation.com/ukraines-small-missiles-are-challenging-a-big-invader-178718">Ukraine’s repeated requests for an Iron Dome system</a>.</p>
<p>Hamas also sent several dozen militants across the border <a href="https://www.jpost.com/israel-news/article-765254">on powered hang-gliders</a>. Their lightweight construction apparently let them avoid radar detection.</p>
<h2>Widening conflict?</h2>
<p>On Sunday, the Israeli army gradually regained control of most of its territory, while the air force kept bombing Gaza. Meanwhile, the rocket fire from Gaza slowed to a trickle.</p>
<p>However, a different rocket threat also appeared. Hezbollah militants in Lebanon <a href="https://www.timesofisrael.com/hezbollah-fires-mortars-at-israel-idf-strike-hits-tent-on-lebanon-border-in-response/">fired several missiles or shells at an Israeli military post</a> in the Golan Heights, on Israel’s northern border. It seemed to be a warning: if Israel retaliated against Gaza, Hezbollah might fire thousands of rockets and missiles into northern Israel.</p>
<p>But the Israeli government, not surprisingly, seems intent on retaliation. It officially declared war and called up its military reserves. A massive invasion of Gaza seems imminent.</p>
<p>So, while civilians in both Israel and Gaza are already mourning the deaths of hundreds, there is likely more bloodshed to come.</p>
<img src="https://counter.theconversation.com/content/215241/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael J. Armstrong 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 bloody ground attacks by Hamas in Israel caused the biggest shock. But the unprecedented scale of rocketry and successful use of armed drones contributed to the surprise.Michael J. Armstrong, Associate Professor, Operations Research, Brock UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2068682023-06-13T04:07:21Z2023-06-13T04:07:21ZVirgin Galactic’s use of the ‘Overview Effect’ to promote space tourism is a terrible irony<p>Virgin Galactic, the space tourism company founded in 2004 by Richard Branson, <a href="https://www.virgingalactic.com/">promotes its flights</a> as offering: </p>
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<p>A Brand New Perspective: Deepen your connection to Earth and to humanity with the transformational experience known as the Overview Effect.</p>
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<p>First discussed in 1987 by space philosopher Frank White, the Overview Effect is a result of viewing Earth from space. </p>
<p>Expressions of the effect range broadly. Astronauts might experience profound awe and wonder at the perception of Earth as a fragile living being. Some suffer crushing grief when considering the harm humans inflict on nature. </p>
<p>While Virgin Galactic promotes access to the Overview Effect as a major drawcard, it is a terrible irony that space tourism is <a href="https://www.thespacereview.com/article/4527/1">enormously damaging</a> for the environment. </p>
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<figcaption><span class="caption">On May 25, Virgin Galactic completed a final test flight before it starts taking paying customers.</span></figcaption>
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Read more:
<a href="https://theconversation.com/seeing-earth-from-space-changes-you-and-you-dont-even-have-to-leave-the-planet-52825">Seeing Earth from space changes you – and you don't even have to leave the planet</a>
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<h2>The Overview Effect</h2>
<p>The Overview Effect is not limited to astronauts from the West. Their Chinese and Russian counterparts have described the same profound connection to Earth when witnessing the planet from space. </p>
<p>As Soviet Russian cosmonaut Yuri Artyushkin <a href="https://psycnet.apa.org/doiLanding?doi=10.1037%2Fcns0000086">reported</a>: </p>
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<p>The feeling of unity is not simply an observation. With it comes a strong sense of compassion and concern for the state of our planet and the effect humans are having on it. It isn’t important in which sea or lake you observe a slick of pollution, or in the forests of which country a fire breaks out, or on which continent a hurricane arises. You are standing guard over the whole of our Earth. </p>
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<p>Until recently, researching the Overview Effect has required interviews with professional astronauts. Today, commercial space tourism is increasing awareness of the phenomenon, particularly when experienced by celebrities with large platforms. </p>
<p>In 2021, Star Trek actor William Shatner completed a suborbital flight with Jeff Bezos’ space tourism company <a href="https://www.blueorigin.com/">Blue Origin</a>. Shatner had anticipated emotions of celebration and joy when viewing “<a href="https://www.nytimes.com/2021/10/13/science/bezos-shatner-star-trek.html">mother and Earth and comfort</a>” from space. Instead, he <a href="https://variety.com/2022/tv/news/william-shatner-space-boldly-go-excerpt-1235395113/">later wrote</a>, he struggled with “the strongest feelings of grief I have ever encountered”. </p>
<p>Shatner attributed his experience to the Overview Effect.</p>
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Read more:
<a href="https://theconversation.com/the-wonders-and-terrors-of-modern-technology-evoke-the-ancient-concept-of-the-sublime-and-present-us-with-a-choice-186909">The wonders and terrors of modern technology evoke the ancient concept of the sublime, and present us with a choice</a>
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<h2>Space flight has a huge environmental impact</h2>
<p>Virgin Galactic promotes the Overview Effect on its <a href="https://www.virgingalactic.com/">homepage</a> as an experience exclusive to space flight. </p>
<p>However, access is extremely costly. While an eager space tourist consents to parting with US$450,000 to experience a profound connection with Earth, the planet itself has no say in receiving the massive pollution a single trip produces.</p>
<p>Rocket emissions impact Earth’s atmosphere, temperatures and the ozone layer at an unprecedented level. A <a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021EF002612">2022 study</a> found space tourism produces black carbon particles that are almost 500 times more efficient at warming the atmosphere than all surface and airline sources of soot combined.</p>
<p>After being released into the upper atmosphere, the black carbon particles circulate for <a href="https://www.cnbc.com/2021/08/27/how-blue-origin-spacex-virgin-galactic-space-race-could-impact-the-atmosphere.html#:%7E:text=Experiencing%20a%20few%20minutes%20of,plane%20continuously%20for%20about%20three">four to five years</a> in a fine layer. This acts as a thin black umbrella <a href="https://www.cnbc.com/2021/08/27/how-blue-origin-spacex-virgin-galactic-space-race-could-impact-the-atmosphere.html#:%7E:text=Experiencing%20a%20few%20minutes%20of,plane%20continuously%20for%20about%20three">absorbing solar radiation while blocking it from reaching Earth’s surface</a>.</p>
<p>A 1.5-hour Virgin Galactic flight generates emissions <a href="https://www.nsr.com/space-com-the-rise-of-space-tourism-could-affect-earths-climate-in-unforeseen-ways-scientists-worry/">equivalent to a ten-hour trans-Atlantic commercial air flight</a>. However, the latter carries hundreds of passengers. With a passenger limit of six, a Virgin Galactic launch <a href="https://theconversation.com/tourisme-spatial-quand-les-plaisirs-de-quelques-uns-polluent-la-planete-de-tous-146552">emits 4.5 tonnes of carbon <em>per person</em></a>. That’s more than twice the Paris Agreement’s recommended annual individual carbon budget. </p>
<p>Space tourism rocket launches don’t currently compare to commercial airline flights in number. But the suborbital transportation and space tourism market is expected to be worth <a href="https://www.prnewswire.com/news-releases/outlook-on-the-sub-orbital-transportation-and-space-tourism-global-market-to-2031---featuring-blue-origin-spacex-and-virgin-galactic-among-others-301333701.html">US$2.58 billion by 2031</a>. It’s growing at an annual rate of 17.15%. </p>
<p>Virgin Galactic is aiming to launch <a href="https://www.cnbc.com/2020/11/06/virgin-galactic-each-spaceport-is-1-billion-annual-revenue-opportunity.html">400 space tourism flights every year</a>. </p>
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Read more:
<a href="https://theconversation.com/space-tourism-rockets-emit-100-times-more-co-per-passenger-than-flights-imagine-a-whole-industry-164601">Space tourism: rockets emit 100 times more CO₂ per passenger than flights – imagine a whole industry</a>
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<figcaption><span class="caption">In this video on its website, Virgin Galactic uses the Overview Effect to promote its space tourism business.</span></figcaption>
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<h2>Caring for Earth doesn’t depend on space flight</h2>
<p>The desirability of the Overview Effect is not the overwhelming emotions experienced when witnessing Earth from space. As was evident in Shatner’s feelings of immense grief, these emotions are not always pleasant. </p>
<p>Instead, researchers, astronauts and space philosophers are interested in the spontaneous and powerful awareness that occurs. Astronauts’ accounts of the moment vary, but a consistent theme emerges: a connection to planet Earth that inspires environmental care.</p>
<p>Importantly, such clarity can be achieved without a suborbital space flight. </p>
<p><a href="https://www.google.com.au/books/edition/The_Overview_Effect/3a2rz-s3JJsC?hl=en">Frank White argues</a> that, while viewing Earth from space produces the “ultimate” Overview Effect, it might also be had while looking at landscapes from a great height – such as a mountain range. Commercial pilots flying at high altitudes have experienced similar phenomena. </p>
<p>And for those considering a Virgin Galactic flight, there are no guarantees. Many astronauts with long careers <a href="https://psycnet.apa.org/doiLanding?doi=10.1037%2Fcns0000086">report</a> never experiencing the Overview Effect. </p>
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<img alt="View of whole Earth photographed by the orbiting Apollo 17 mission and dubbed 'Blue Marble'" src="https://images.theconversation.com/files/530799/original/file-20230608-27-brv39q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/530799/original/file-20230608-27-brv39q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/530799/original/file-20230608-27-brv39q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/530799/original/file-20230608-27-brv39q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/530799/original/file-20230608-27-brv39q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=755&fit=crop&dpr=1 754w, https://images.theconversation.com/files/530799/original/file-20230608-27-brv39q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=755&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/530799/original/file-20230608-27-brv39q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=755&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Being able to see the whole Earth from space was regarded as a transformative moment, but people can have environmental epiphanies without flying into space.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/content/blue-marble-image-of-the-earth-from-apollo-17">NASA/Apollo 17</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/keen-to-sign-up-for-space-tourism-here-are-6-things-to-consider-besides-the-price-tag-164940">Keen to sign up for space tourism? Here are 6 things to consider (besides the price tag)</a>
</strong>
</em>
</p>
<hr>
<h2>Environmental epiphanies happen on Earth</h2>
<p>Spontaneous clarity about the importance of nature can occur while standing on solid ground. “<a href="https://www.jstor.org/stable/26506666#:%7E:text=The%20working%20definition%20of%20Environmental,shifts%20in%20a%20meaningful%20manner.">Environmental epiphanies</a>” are well documented and have no connection to specific religious or cultural beliefs. </p>
<p>Involving profound emotions and sudden awareness similar to the Overview Effect, environmental epiphanies can be accessed for free in mundane locations – such as reading a book at home. </p>
<p>And, like the Overview Effect, environmental epiphanies can lead to lasting change.</p>
<p>As space tourism continues to “take off”, misaligned marketing tactics like Virgin Galactic’s promotion of the Overview Effect must be scrutinised. </p>
<p>Being launched into space – and the massive pollution the process creates – isn’t necessary for us to want to sustain our Earth.</p><img src="https://counter.theconversation.com/content/206868/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ariane Moore 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 Overview Effect describes the transformative impact of seeing Earth from space and feeling profoundly connected to our planet and concerned for it. That’s at odds with the impact of space tourism.Ariane Moore, PhD Candidate in Philosophy, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2042482023-04-20T19:59:23Z2023-04-20T19:59:23ZSpaceX launches most powerful rocket in history in explosive debut – like many first liftoffs, Starship’s test was a successful failure<figure><img src="https://images.theconversation.com/files/522218/original/file-20230420-1011-46fy37.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C6403%2C4204&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Starship, the most powerful rocket ever built, launched from a spaceport in Texas. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/SpaceXStarshipTestFlight/1b6cc6f972fc40678d74b21ec7aae320/photo?Query=starship%20spacex%20launch&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=69&currentItemNo=5">AP Photo/Eric Gay)</a></span></figcaption></figure><p>On April 20, 2023, a new SpaceX rocket called Starship exploded over the Gulf of Mexico three minutes into its first flight ever. SpaceX is calling the test launch a success, despite the fiery end result. As a <a href="https://scholar.google.com/citations?user=PxIOz7cAAAAJ&hl=en">space policy expert</a>, I agree that the “rapid unscheduled disassembly” – the term SpaceX uses when its rockets explode – was a very successful failure.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A large rocket standing next to a tower." src="https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=797&fit=crop&dpr=1 600w, https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=797&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=797&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1001&fit=crop&dpr=1 754w, https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1001&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/522219/original/file-20230420-25-atilr4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1001&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 full Starship stack comprises a Starship spacecraft (in black) on top of a rocket dubbed Super Heavy (in silver) and is nearly 400 feet (120 meters) tall.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/195131646@N04/51912424446">Hotel Marmot/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>The most powerful rocket ever built</h2>
<p>This launch was the first fully integrated test of SpaceX’s new Starship. Starship is the <a href="https://www.spacex.com/vehicles/starship/">most powerful rocket ever developed</a> and is designed to be fully reusable. It is made of two different stages, or sections. The first stage, called Super Heavy, is a collection of 33 individual engines and provides <a href="https://spaceflightnow.com/2023/04/17/how-spacexs-starship-stacks-up-to-other-rockets/">more than twice the thrust</a> of a Saturn V, the rocket that sent astronauts to the Moon in the 1960s and 1970s.</p>
<p>The first stage is designed to get the rocket to about 40 miles (65 kilometers) above Earth. Once Super Heavy’s job is done, it is supposed to separate from the rest of the craft and land safely back on the surface to be used again. At that point the second stage, called the Starship spacecraft, is supposed to ignite its own engines to carry the payload – whether people, satellites or anything else – into orbit.</p>
<h2>An explosive first flight</h2>
<p>While parts of Starship have been <a href="https://www.nytimes.com/interactive/2023/04/16/science/spacex-starship-rocket-launch.html">tested previously</a>, the launch on April 20, 2023, was the <a href="https://www.space.com/spacex-starship-rocket-super-heavy-launch-what-time">first fully integrated test</a> with the Starship spacecraft stacked on top of the Super Heavy rocket. If it had been successful, once the first stage was spent, it would have separated from the upper stage and crashed into the Gulf of Mexico. Starship would then have continued on, eventually crashing 155 miles (250 kilometers) off of Hawaii.</p>
<p>During the SpaceX livestream, the team stated that the primary goal of this mission was to get the rocket off the launch pad. It accomplished that goal and more. Starship flew for <a href="https://www.space.com/spacex-starship-first-space-launch">more than three minutes</a>, passing through what engineers call “max Q” – the moment at which a rocket experiences the most physical stress from acceleration and air resistance.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A cloud of fire and smoke in the sky with pieces falling Earthward." src="https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=539&fit=crop&dpr=1 754w, https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=539&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/522220/original/file-20230420-1377-gg5xm8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=539&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 Starship spacecraft and Super Hheavy rocket were unable to separate during the flight, so engineers blew up the full rocket.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/SpaceXStarshipTestFlight/d9babe8dbe424e19869d3283a61fc199/photo?Query=starship%20spacex%20launch&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=69&currentItemNo=13">AP Photo/Eric Gay</a></span>
</figcaption>
</figure>
<p>According to SpaceX, a few things went wrong with the launch. First, <a href="https://twitter.com/wapodavenport/status/1649122093391282197">multiple engines went out</a> sometime before the point at which the Starship spacecraft and the Super Heavy rocket were supposed to separate from each other. The two stages were also unable to separate at the predetermined moment, and with the two stages stuck together, the rocket began to tumble end over end. It is still unclear what specifically caused this failure.</p>
<p>Starship is almost 400 feet (120 meters) tall and weighs 11 million pounds (4.9 million kilograms). An out-of-control rocket full of highly flammable fuel is a very dangerous object, so to prevent any harm, SpaceX engineers triggered the self-destruct mechanism and blew up the entire rocket over the Gulf of Mexico. </p>
<p>All modern rockets have mechanisms built into them that allow engineers to <a href="https://www.patrick.spaceforce.mil/News/Article-Display/Article/2666657/new-flight-termination-system-improves-launch-tempo/">safely destroy the rocket in flight</a> if need be. SpaceX itself has <a href="https://www.youtube.com/watch?v=K5Vw2ZDe-G0">blown up many of its own rockets</a> during testing. </p>
<h2>Success or failure?</h2>
<p>Getting to space is hard, and it is not at all unusual for new rockets to experience problems. In the past two years, both <a href="https://www.space.com/south-korea-nuri-rocket-launch-failure">South Korea</a> and <a href="https://apnews.com/article/japan-space-rocket-h3-failure-observation-satellite-dc137cb55bb4b72537508f1319989ce1">Japan</a> have attempted to launch new rockets that also failed to reach orbit. Commercial companies such as <a href="https://spacenews.com/virgin-orbit-elaborates-on-potential-cause-of-launcherone-failure/">Virgin Orbit</a> and <a href="https://www.nytimes.com/2023/03/23/science/relativity-space-launch-terran.html">Relativity Space</a> have also lost rockets recently. None of these were crewed missions, and in most of these failed launches, flight engineers purposefully destroyed the rockets after problems arose.</p>
<p>SpaceX’s approach to testing is different from that of other groups. Its company philosophy is to <a href="https://arstechnica.com/science/2020/02/elon-musk-says-spacex-driving-toward-orbital-starship-flight-in-2020/">fail fast</a>, find problems and fix them with the next rocket. This is different from the more <a href="https://280group.com/product-management-blog/behind-the-product-nasa-sls-vs-spacex-starship/#:%7E:text=SLS%20has%20a%20payload%20capacity,known%20as%20the%20waterfall%20method.">traditional approach</a> taken by organizations such as NASA that spend far more time identifying and planning for possible problems before attempting a launch.</p>
<p>The traditional approach tends to be slow. The development of NASA’s Space Launch System – the rocket that will <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">take astronauts to the Moon</a> as part of the Artemis program – took more than 10 years before its <a href="https://theconversation.com/nasas-artemis-1-mission-to-the-moon-sets-the-stage-for-routine-space-exploration-beyond-earths-orbit-heres-what-to-expect-and-why-its-important-189447">first launch this past November</a>. SpaceX’s method has allowed the company to move much faster but can be costlier because of the time and resources it takes to build new rockets. </p>
<p>SpaceX engineers will look to identify the specific cause of the problem so that they can fix it for the next test launch. With this approach, launches like this first Starship test are successful failures that will help SpaceX reach its eventual goal of sending astronauts to Mars.</p><img src="https://counter.theconversation.com/content/204248/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>The launch of a new rocket is always an exciting event. SpaceX’s ‘go fast and fail’ approach means that even though the test ended with engineers blowing up the rocket, it was a valuable first flight.Wendy Whitman Cobb, Professor of Strategy and Security Studies, Air UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2034732023-04-12T12:11:31Z2023-04-12T12:11:31ZIs the US in a space race against China?<figure><img src="https://images.theconversation.com/files/520344/original/file-20230411-24-ym4ttx.jpg?ixlib=rb-1.1.0&rect=112%2C90%2C4898%2C2937&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Both the U.S. and China have plans to establish bases on the Moon in the near future.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/two-astronauts-on-the-moon-an-american-flag-in-royalty-free-image/103405591?phrase=two%20flags%20on%20moon&adppopup=true">Caspar Benson/fStop via Getty Images</a></span></figcaption></figure><p>Headlines proclaiming the rise of a new “space race” <a href="https://theweek.com/space/1019765/the-new-space-race#:%7E:text=The%20original%20space%20race%20was,with%20a%20new%20competitor%3A%20China.">between the U.S. and China</a> have become common in news coverage following many of the exciting launches in recent years. Experts have pointed to China’s <a href="https://thehill.com/opinion/technology/584314-us-china-space-cooperation-is-up-in-the-air-more-than-ever/">rapid advancements</a> in space as evidence of an emerging landscape where China is <a href="https://www.politico.com/news/2023/01/01/we-better-watch-out-nasa-boss-sounds-alarm-on-chinese-moon-ambitions-00075803">directly competing</a> with the U.S. for supremacy.</p>
<p>This idea of a space race between China and the U.S. sounds convincing given the broader narrative of China’s rise, but how accurate is it? As a professor who <a href="https://faculty.af.edu/esploro/profile/svetla_benitzhak">studies space and international relations</a>, my research aims to quantify the power and capabilities of different nations in space. When I look at various capacities, the data paints a much more complex picture than a tight space race between the U.S. and China. At least for now, the reality looks more like what I call a complex hegemony – one state, the U.S., is still <a href="http://dx.doi.org/10.1007/978-3-030-97711-5_14">dominating in key space capabilities</a>, and this lead is further amplified by a <a href="https://doi.org/10.1016/j.spacepol.2021.101444">strong network of partners</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A rocket taking off." src="https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=395&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=395&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=395&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=497&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=497&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520346/original/file-20230411-20-tsr0m6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=497&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">SpaceX rockets carry hundreds of private satellites into orbit each year from the seven active U.S. spaceports.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/spacex-falcon-9-rocket-carrying-a-batch-of-56-starlink-news-photo/1249311447?adppopup=true">SOPA Images/LightRocket via Getty Images</a></span>
</figcaption>
</figure>
<h2>A clear leader makes for a boring race</h2>
<p>Calling the current situation a race implies that the U.S. and China have roughly equal capabilities in space. But in several key areas, the U.S. is far ahead not only of China, but of all other spacefaring nations combined.</p>
<p>Starting with spending: In 2021, the U.S. space budget was roughly <a href="https://www.thespacereport.org/resources/government-space-spending-increases-19-from-2020-to-2021/">US$59.8 billion</a>. China has been investing heavily in space and rocket technology over the last decade and has doubled its spending in the last five years. But with an estimated budget of <a href="https://www.thespacereport.org/resources/government-space-spending-increases-19-from-2020-to-2021/">$16.18 billion</a> in 2021, it is still spending less than a third of the U.S. budget.</p>
<p>The U.S. also leads significantly in the number of active satellites. Currently, there are <a href="https://www.ucsusa.org/resources/satellite-database">5,465 total operational satellites</a> in orbit around Earth. The U.S. operates 3,433, or 63% of those. In contrast, China has 541.</p>
<p>Similarly, the U.S. has more <a href="https://aerospace.csis.org/spaceports-of-the-world/">active spaceports</a> than China. With <a href="https://aerospace.csis.org/spaceports-of-the-world/">seven operational launch sites at home and abroad</a> and at least <a href="https://www.faa.gov/space/spaceports_by_state">13 additional</a> spaceports <a href="https://www.visualcapitalist.com/wp-content/uploads/2022/10/worlds-rocket-launch-sites-fullsize.html">in development</a>, the U.S. has more options to launch payloads into various orbits. In contrast, China has only <a href="https://aerospace.csis.org/data/spaceports-of-the-world/">four operational spaceports</a> with <a href="https://www.visualcapitalist.com/wp-content/uploads/2022/10/worlds-rocket-launch-sites-fullsize.html">two more planned</a>, all located within its own territory.</p>
<h2>Parity with nuance</h2>
<p>While the U.S. may have a clear advantage over China in many areas of space, in some measures, the differences between the two countries are more nuanced.</p>
<p>In 2021, for instance, China attempted <a href="https://www.thespacereport.org/register/the-space-report-2021-quarter-4-pdf-download/">55 orbital launches</a>, four more than the U.S.’s 51. The total numbers may be similar, but the rockets carried very different payloads to orbit. The vast majority – 84% – of Chinese launches had government or military payloads intended mostly for electronic intelligence and optical imaging. Meanwhile, in the U.S., 61% of launches were for nonmilitary, academic or commercial use, predominantly for Earth observation or telecommunications.</p>
<p>Space stations are another area where there are important differences hiding beneath the surface. Since the 1990s, the U.S. has worked with <a href="https://www.nasa.gov/mission_pages/station/cooperation/index.html">14 other nations</a>, including Russia, to operate the <a href="https://www.nasa.gov/feature/facts-and-figures">International Space Station</a>. The ISS is quite large, with 16 modules, and has driven <a href="https://www.nasa.gov/mission_pages/station/research/news/iss-20-years-20-breakthroughs">technological and scientific breakthroughs</a>. But the ISS is now 24 years old, and participating nations are planning to <a href="https://www.nasa.gov/feature/nasa-provides-updated-international-space-station-transition-plan">retire it in 2030</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram of the Tiangong space station." src="https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520345/original/file-20230411-20-xi403n.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">Construction of China’s Tiangong space station began in 2021, and the small, three-module station opened for research in December 2022.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Tiangong_Space_Station_config_2022_EN.jpg#/media/File:Tiangong_Space_Station_config_2022_EN.jpg">Shujianyang/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The Chinese <a href="https://www.nytimes.com/interactive/2021/science/tiangong-space-station.html">Tiangong space station</a> is the new kid on the block. Construction was only <a href="https://theconversation.com/chinas-new-space-station-opens-for-business-in-an-increasingly-competitive-era-of-space-activity-195882">completed in late 2022</a>, and it is much smaller – with only three modules. China has built and launched all of the different parts and remains the sole operator of the station, despite <a href="http://www.xinhuanet.com/english/2018-05/29/c_137213186.htm">having invited others to join</a>.</p>
<p>China is undoubtedly expanding its space capabilities, and in a report published in August 2022, the Pentagon <a href="https://www.defenseone.com/technology/2022/08/china-could-overtake-us-space-without-urgent-action-report/376261/">predicted that China would surpass U.S. capabilities</a> in space as early as 2045. However, it is unlikely that the U.S. will remain stagnant, as it continues to increase funding for space.</p>
<h2>Allies as force multipliers</h2>
<p>A major point of difference between the U.S. and China is the nature and number of international collaborations. </p>
<p>For decades, NASA has been fruitfully cultivating <a href="https://www.nasa.gov/oiir/nasa-partners-worldwide">international</a> and <a href="https://www.nasa.gov/subject/3124/commercial-partners/">commercial</a> partnerships in everything from developing specific space technologies to flying humans into space. The U.S. government has also <a href="https://breakingdefense.com/2023/02/spacecom-expands-allied-industy-cooperation-gen-dickinson/">signed 169 space data sharing agreements</a> with 33 states and intergovernmental organizations, 129 with commercial partners and seven with academic institutions.</p>
<p>China also has allies that help with space – most notably <a href="https://www.bloomberg.com/news/articles/2023-02-26/china-russia-alliance-in-space-stumbles-in-bid-to-surpass-the-us">Russia</a> and members of the <a href="http://www.apsco.int/">Asia-Pacific Space Cooperation Organization</a>, including Iran, Pakistan, Thailand and Turkey. China’s collaborators are, however, fewer in number and have far less developed space capabilities. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man signing a document with a Brazilian and American flag on the desk." src="https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/520347/original/file-20230411-28-nwvax6.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">In just two years, 24 nations, including Brazil, have joined the U.S.-led Artemis Accords. This international agreement outlines the goals of space exploration in the near future.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Assinatura_de_termo_de_coopera%C3%A7%C3%A3o_-_Programa_Artemis_BR_US_(50720570051).jpg#/media/File:Assinatura_de_termo_de_coopera%C3%A7%C3%A3o_-_Programa_Artemis_BR_US_(50720570051).jpg">Ministério da Ciência, Tecnologia e Inovações/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Efforts to return to the surface of the Moon excellently highlight this difference in ally support and synergy. Both the U.S. and China have plans to send people to the surface of the Moon and to establish lunar bases in the near future. These competing lunar aims are often <a href="https://time.com/longform/race-to-the-moon/">cited as evidence of the space race</a>, but they are very different in terms of partnerships and scope.</p>
<p>In 2019, <a href="https://spacenews.com/china-russia-to-cooperate-on-lunar-orbiter-landing-missions/">Russia and China agreed</a> to jointly go to the Moon by 2028. Russia is contributing its Luna landers and Oryol crewed orbiters, while China is improving its Chang’e robotic spacecraft. Their future International Lunar Research Station is “<a href="https://www.space.com/russia-china-moon-research-station-agreement">open to all interested parties and international partners</a>,” but, to date, no additional countries have committed to the Chinese and Russian effort.</p>
<p>In contrast, since 2020, 24 nations have joined the U.S.-led <a href="https://www.nasa.gov/specials/artemis-accords/index.html">Artemis Accords</a>. This international agreement outlines shared <a href="https://www.nasa.gov/specials/artemis-accords/index.html">principles of cooperation</a> for future space activity and, through the Artemis Program, specifically aims to return people to the Moon by 2025 and establish a Moon base and lunar space station soon after.</p>
<p>In addition to the broad international participation, the Artemis Program has contracted with a staggering <a href="https://www.nasa.gov/directorates/spacetech/solicitations/tipping_points/2020_selections">number of private companies</a> to develop a <a href="https://www.nasa.gov/press-release/nasa-announces-partners-to-advance-tipping-point-technologies-for-the-moon-mars">range of technologies</a>, from <a href="https://www.nasa.gov/press-release/nasa-selects-five-us-companies-to-mature-artemis-lander-concepts">lunar landers</a> to <a href="https://www.nasa.gov/press-release/nasa-icon-advance-lunar-construction-technology-for-moon-missions">lunar construction methods</a> and <a href="https://www.nasa.gov/directorates/spacetech/centennial_challenges/nasa-announces-newest-winners-in-break-the-ice-lunar-challenge.html">more</a>.</p>
<h2>China is not the only game in town</h2>
<p>While China may seem like the main competitor of the U.S. in space, other countries have space capabilities and aspirations that rival those of China.</p>
<p><a href="https://www.bbc.com/news/science-environment-64002977">India</a> spends billions on space and plans to <a href="https://in.mashable.com/science/44883/india-is-returning-to-the-moon-chandrayaan-3-mission-will-launch-this-year">return to the Moon</a>, possibly <a href="https://www.secretsofuniverse.in/lunar-exploration-mission-isro-jaxa/">with Japan</a>, in the near future. <a href="https://www.nature.com/articles/d41586-022-01252-7">South Korea, Israel, Japan, the United Arab Emirates</a>, <a href="https://www.pbs.org/newshour/world/turkey-sets-sights-on-moon-mission-in-2023">Turkey</a>, <a href="https://cordis.europa.eu/article/id/27263-germany-plans-moon-mission">Germany</a> and <a href="https://www.politico.eu/article/europe-told-to-aim-for-a-moon-mission/">the European Union</a> are also planning independent lunar missions. Japan has developed impressive technological space capabilities, including rendezvous proximity technology to send a <a href="https://solarsystem.nasa.gov/missions/hayabusa-2/in-depth/">spacecraft to an asteroid and bring samples back to Earth</a>, that rival and even surpass <a href="https://spacenews.com/chinas-shijian-21-spacecraft-docked-with-and-towed-a-dead-satellite/">those of China</a>.</p>
<p>In the past, the space race was about who could reach the stars first and return home. Today, the goal has shifted to surviving and even thriving in the harsh environment of space. I believe it is not surprising that, despite its decisive lead, the U.S. has partnered with others to go to the Moon and beyond. China is doing the same, but on a smaller scale. The picture that emerges is not of a “race” but of complex system with the U.S. as a leader working closely with extensive networks of partners.</p><img src="https://counter.theconversation.com/content/203473/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The views expressed are those of the author and do not reflect the official position of the U.S. Department of Defense, or of any organization the author is affiliated with, including the U.S. Air Force and the U.S. Space Force</span></em></p>China has invested massively in its space capabilities in recent years and is now a major competitor with the US. But according to a space policy expert, the US still dominates space by most measures.Svetla Ben-Itzhak, Assistant Professor of Space and International Relations, Air UniversityLicensed 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/2024002023-03-29T19:26:53Z2023-03-29T19:26:53ZAirplanes face a growing risk of being hit by uncontrolled re-entries of rockets used to launch satellites<figure><img src="https://images.theconversation.com/files/517907/original/file-20230328-21-a6pz02.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3996%2C1944&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A SpaceX Falcon 9 rocket carrying Starlink satellites launches on Aug. 19, 2022. The Falcon 9 is a reusable rocket and its re-entry is controlled after launch, reducing debris.</span> <span class="attribution"><span class="source">(Malcolm Denemark/Florida Today via AP)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/airplanes-face-a-growing-risk-of-being-hit-by-uncontrolled-re-entries-of-rockets-used-to-launch-satellites" width="100%" height="400"></iframe>
<p>On May 11, 2020 a deadly threat flew from Los Angeles to New York City in under nine minutes. It was a <a href="https://www.nbcnews.com/science/space/chinese-rocket-debris-passed-over-n-y-c-l-it-n1206311">20-tonne Chinese Long March 5B rocket body passing around 60 miles overhead</a>. </p>
<p>Just 15 minutes later, the rocket body re-entered the atmosphere and broke into pieces, including a <a href="https://www.forbes.com/sites/jonathanocallaghan/2020/05/12/parts-of-a-chinese-rocket-may-have-fallen-on-an-african-village/">12-metre-long pipe that crashed into a village in the Ivory Coast</a>.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1260222397350887425"}"></div></p>
<p>The rocket body had completed its mission and been abandoned in orbit, left to return to the surface in an uncontrolled way. It posed an indiscriminate threat to people across the globe — on the ground, at sea, and in aircraft in flight. <a href="https://www.newscientist.com/article/2327922-10-per-cent-chance-falling-rockets-will-hit-someone-in-next-decade/">The probability of a lethal impact was very small</a>, but the consequences could have been severe.</p>
<h2>Weighing cost against risk</h2>
<p>At the time, the Federal Aviation Administration (FAA) decided not to close U.S. airspace — denying planes permission to fly within a designated area — along the rocket body’s path. The timeframe for making such a decision was very short and fraught with uncertainty, while the economic costs to airlines and passengers were certain and large.</p>
<p>In circumstances like these, decision-makers have to weigh the economic costs against taking no action but accepting a small probability of casualties. The FAA chose the latter.</p>
<p>On Nov. 4, 2022, Spain and France closed parts of their airspace for 40 and 60 minutes respectively, as <a href="https://www.theguardian.com/world/2022/nov/04/spanish-airspace-partially-closed-as-chinese-rocket-debris-falls-to-earth">another Chinese Long March 5B rocket body was due to re-enter the atmosphere uncontrolled</a>. The rocket body passed harmlessly overhead, before breaking up over the Pacific Ocean. </p>
<p><a href="https://spacenews.com/long-march-5b-stage-reenters-over-pacific-ocean-after-forcing-airspace-closures-in-europe/">More than 300 flights were disrupted</a> by the Spanish airspace closure alone, costing airlines and passengers millions of Euros.</p>
<p>Which approach was correct? Nobody likes delays, yet we all expect airlines and regulators to put safety first. Nevertheless, why are aviation agencies being forced to make these decisions at all?</p>
<h2>No confirmed instances</h2>
<p>An aircraft in flight could be seriously damaged by just 300 grams of space debris impacting an engine, windshield or other critical surface. Although there are no confirmed instances of space debris hitting an aircraft in flight, in 1996 the windscreen of a Boeing 757 was cracked by <a href="https://aerospaceamerica.aiaa.org/features/dodging-debris/">an unknown object while flying at 31,500 feet</a>. </p>
<p>In 2013, another Boeing 757 had one side of <a href="https://www.independent.co.uk/news/world/asia/chinese-passenger-jet-makes-emergency-landing-after-being-hit-by-ufo-unidentified-foreign-object-at-26-000-feet-8654040.html">its nose-cone punched in by an unidentified object while flying at 26,000 feet</a>. Bird strikes were unlikely in these instances.</p>
<p>There’s no need for any of us to worry. The probability of an airplane being struck by space debris is extremely small — much smaller than a <a href="https://www.faa.gov/airports/airport_safety/wildlife/faq">bird strike</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a photograph showing a rocket taking off in the distance while a crowd of people watch" src="https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517560/original/file-20230327-22-ht1uqe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">People watch the Long March 5B Y3 carrier rocket lift off from the Wenchang Space Launch Center in southern China on July 24, 2022. Authorities warned of potential danger to aircraft and ships.</span>
<span class="attribution"><span class="source">(Zhang Liyun/Xinhua via AP, File)</span></span>
</figcaption>
</figure>
<p>But even very small probabilities can have severe consequences that justify regulatory action. In 2021, the AstraZeneca COVID-19 vaccine was linked to <a href="https://www.ema.europa.eu/en/news/astrazenecas-covid-19-vaccine-ema-finds-possible-link-very-rare-cases-unusual-blood-clots-low-blood">a very small risk of blood clots — a total of 222 cases among 34 million people</a>, or 0.0007 per cent. </p>
<p>A number of countries responded by curtailing and, in the case of the U.S., not licensing the use of AstraZeneca, <a href="https://www.yalemedicine.org/news/coronavirus-vaccine-blood-clots">thus favoring more expensive MRNA vaccines</a> .</p>
<p>Today, two factors combine to increase the probability of an airplane being struck by space debris: increasing air traffic and increasing uses of space. COVID-19 aside, <a href="https://www.icao.int/about-icao/Pages/annual-reports.aspx">the number of airline flights each year has doubled since the millennium</a>. </p>
<p>In just the last four years the number of active and defunct satellites in low Earth orbit has also doubled, <a href="https://planet4589.org/space/gcat/data/derived/currentcat.html">from approximately 3,000 to more than 8,000</a>.</p>
<h2>Controlled versus uncontrolled</h2>
<p>Satellites are launched using rockets, and while some rocket bodies are brought back to Earth in a controlled manner, <a href="https://doi.org/10.1016/j.actaastro.2021.03.030">many are simply abandoned in orbit</a>.</p>
<p>Uncontrolled re-entries occur because objects orbiting at low enough altitudes still feel the effects of the uppermost portions of Earth’s atmosphere, creating a drag that ensures an eventual re-entry. Predicting these re-entries is very difficult due to a <a href="http://iaass.space-safety.org/wp-content/uploads/sites/24/2021/12/Making-Space-Safe-and-Sustainable-A4-v1-3.pdf">myriad of factors</a> that include variations in the atmosphere itself.</p>
<p>In contrast, a controlled re-entry is performed by using an engine burn that directs the rocket body to a remote area of ocean or a recovery zone. Some fuel must be retained in the rocket body for this purpose, and the engines must be able to reignite.</p>
<p>Yet many operators still <a href="https://doi.org/10.1016/j.jsse.2019.02.001">choose to use uncontrolled re-entries</a>, presumably to avoid the additional costs associated with technological upgrades and extra fuel. </p>
<p>Even SpaceX, an industry leader in technology development, sometimes abandons <a href="https://everydayastronaut.com/ses-18-ses-19-falcon-9-block-5/">the second stages of its rockets after lifting satellites destined for geosynchronous orbit</a>. In 2016, two pressure vessels — each the size of a washing machine — from one such stage reached the ground intact, <a href="https://spaceflight101.com/falcon-9-jcsat-16/spacex-rocket-parts-rain-down-over-indonesia/">landing in Indonesia</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/OhBw5yaR_SU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A controlled re-entry of the European Space Agency’s automated transfer vehicle Jules Verne in Sept. 2008.</span></figcaption>
</figure>
<p>Aviation bodies are taking notice, <a href="https://www.icao.int/secretariat/SecretaryGeneral/Documents/Addresses%20and%20Messages/20230217_SG-SPEECH-SpaceDerbisWorkshop.pdf">including the International Civil Aviation Organization</a> and <a href="https://www.alpa.org/-/media/ALPA/Files/pdfs/news-events/letters/2021/0514-icao-fang-liu-rocket.pdf?la=en">the Air Line Pilots Association</a>. </p>
<p>In March 2023, the <a href="http://outerspaceinstitute.ca/">Montréal Recommendations on Aviation Safety and Uncontrolled Space Object Reentries</a> were released. The recommendations were compiled by international experts, including the Inspector General of the French Space Agency and the Chief of Space Safety in the U.S. Department of the Air Force.</p>
<p>Recognizing that the “use of space by any single state has global implications, with risks potentially exported from launching states to other states,” the recommendations call on states to “establish requirements to avoid uncontrolled re-entries of space objects.”</p>
<p>Will it take a major accident, such as a catastrophic strike to an airplane, before public concern forces governments to require that all rocket bodies be brought back to Earth in a controlled manner?</p>
<h2>Successful policies</h2>
<p>We’ve been here before. In the 1970s, a growing risk to oceans from oil spills led <a href="https://www.jstor.org/stable/24113126">to calls for a requirement for double hulls on tankers</a>. The shipping industry, concerned about increased costs, was able to stifle these efforts — until 1989, when <a href="https://darrp.noaa.gov/oil-spills/exxon-valdez">the Exxon Valdez spilled roughly 11 million gallons of oil into Alaska’s Prince William Sound</a>.</p>
<p>Suddenly, the issue of oil spills was a matter of public concern, and after the National Transportation Safety Board concluded that a double hull would <a href="https://www.ntsb.gov/investigations/AccidentReports/Reports/MAR9004.pdf">have substantially reduced if not eliminated the spill</a>, the U.S. government required <a href="https://response.restoration.noaa.gov/about/media/final-farewell-oil-tankers-single-hulls.html">all new tankers calling at U.S. ports to have double hulls</a>. </p>
<p>This unilateral move prompted the International Maritime Organization to amend the International Convention for the Prevention of Pollution from Ships in 1992 to require double hulls on new tankers. And, through further amendments in 2001 and 2003, to <a href="http://www.imo.org/en/OurWork/Environment/Pages/constructionrequirements.aspx">accelerate the retirement of single-hulled tankers</a>. </p>
<p>The 1992 amendment has since been ratified by 150 nations <a href="http://www.imo.org/en/About/Conventions/Pages/StatusOfConventions.aspx">representing 98 per cent of the world’s shipping tonnage</a>.</p>
<p>One of the most informative aspects of this precedent is that the U.S. adopted a double-hull requirement before any other nation, and this move then prompted successful multilateral law-making.</p>
<p>Today, uncontrolled rocket body re-entries are another international safety issue where the U.S. could lead.</p>
<p>The FAA licenses the majority of the world’s space launches and regulates one of the largest aviation industries. It is perfectly positioned to spur international change — before an airplane full of passengers is struck from the sky.</p>
<p><em>This is a corrected version of a story originally published on March 29. The earlier story said that the Montréal Recommendations on Aviation Safety and Uncontrolled Space Object Reentries was published in 2022 instead of 2023.</em></p><img src="https://counter.theconversation.com/content/202400/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Byers receives funding from the Canada Research Chairs Program, Social Sciences and Humanities Research Council of Canada, Natural Sciences and Engineering Research Council of Canada, New Frontiers in Research Fund, and the Department of National Defence. He is affiliated with the Outer Space Institute and the Salt Spring Forum. </span></em></p><p class="fine-print"><em><span>Aaron Boley receives funding from the Canada Research Chairs Program, Natural Sciences and Engineering Research Council of Canada, New Frontiers in Research Fund, and the Department of National Defence. He is affiliated with the Outer Space Institute. </span></em></p>Rockets used to launch satellites fall back to Earth, and as their number grows, the risk faced by people living on the ground — or flying in airplanes — increases.Michael Byers, Professor, Political Science, University of British ColumbiaAaron Boley, Associate Professor, Physics and Astronomy, University of British ColumbiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1958822022-12-09T13:28:35Z2022-12-09T13:28:35ZChina’s new space station opens for business in an increasingly competitive era of space activity<figure><img src="https://images.theconversation.com/files/499869/original/file-20221208-12532-d6cyhl.jpg?ixlib=rb-1.1.0&rect=865%2C59%2C3539%2C2581&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Three taikonauts rode aboard the Shenzhou 15 mission on their way to China's new Tiangong space station.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-manned-spaceship-shenzhou-15-atop-the-long-march-2f-y15-news-photo/1245233337?phrase=shenzhou%2015&adppopup=true">Xinhua News Agency via Getty Images</a></span></figcaption></figure><p>The International Space Station is no longer the only place where humans can live in orbit.</p>
<p>On Nov. 29, 2022, the <a href="https://www.nytimes.com/2022/11/29/world/asia/china-space-launch-astronauts.html">Shenzhou 15 mission launched</a> from China’s Gobi Desert carrying three taikonauts – the Chinese word for astronauts. Six hours later, they reached their destination, China’s recently completed space station, called Tiangong, which means “heavenly palace” in Mandarin. The three taikonauts replaced the existing crew that helped wrap up construction. With this successful mission, China has become just the third nation to operate a permanent space station.</p>
<p>China’s space station is an achievement that solidifies the country’s position alongside the U.S. and Russia as one of the world’s top three space powers. As scholars of <a href="https://scholar.google.com/citations?user=YtgRGx0AAAAJ&hl=en&oi=ao">space law</a> and <a href="https://scholar.google.com/citations?user=YnVdvEYAAAAJ&hl=en&oi=ao">space policy</a> who lead the Indiana University Ostrom Workshop’s <a href="https://ostromworkshop.indiana.edu/research/space-governance/index.html">Space Governance Program</a>, we have been following the development of the Chinese space station with interest. </p>
<p>Unlike the collaborative, U.S.-led International Space Station, Tiangong is entirely built and run by China. The successful opening of the station is the beginning of some exciting science. But the station also highlights the country’s policy of self-reliance and is an important step for China toward achieving larger space ambitions among a changing landscape of power dynamics in space.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram of the space station." src="https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499872/original/file-20221208-17536-p3m533.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">The Tiangong space station is much smaller than the International Space Station and consists of three modules.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Tiangong_Space_Station_config_2022_EN.jpg#/media/File:Tiangong_Space_Station_config_2022_EN.jpg">Shujianyang/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Capabilities of a Chinese station</h2>
<p>The Tiangong space station is the culmination of three decades of work on the <a href="http://en.cmse.gov.cn/aboutcms/">Chinese manned space program</a>. The station is 180 feet (55 meters) long and is <a href="https://www.engineering.com/story/battle-of-the-space-stations-iss-vs-tiangong">comprised of three modules</a> that were launched separately and connected in space. These include one core module where a maximum of six taikonauts can live and two experiment modules for a total of 3,884 cubic feet (110 cubic meters) of space, about one-fifth the size of the International Space Station. The station also has an <a href="https://academic.hep.com.cn/fem/EN/10.15302/J-FEM-2018202">external robotic arm</a>, which can support activities and <a href="http://www.aerospacechina.org/EN/abstract/abstract421.shtml">experiments outside the station</a>, and three docking ports for resupply vehicles and manned spacecraft. </p>
<p>Like China’s aircraft carriers and other spacecraft, Tiangong is <a href="https://science.howstuffworks.com/chinese-space-station-news.htm">based on a Soviet-era design</a> – it is pretty much a copy of the Soviet Mir space station from the 1980s. But the Tiangong station has been heavily modernized and improved. </p>
<p>The Chinese space station is slated to stay in orbit for 15 years, with plans to <a href="https://www.cnn.com/2022/11/29/world/china-space-station-astronauts-launch-scn/index.html">send two six-month crewed missions</a> and two cargo missions to it annually. The science experiments have already begun, with a planned study involving <a href="https://www.scmp.com/news/china/science/article/3198222/chinese-scientists-plan-monkey-reproduction-experiment-space-station">monkey reproduction</a> commencing in the station’s biological test cabinets. Whether the monkeys will cooperate is an entirely different matter.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A person in a space suit outside of a space station." src="https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499875/original/file-20221208-19047-qh64s7.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">This image, captured from a video feed at the Beijing Aerospace Center on Nov. 17, 2022, shows taikonauts working on the Tiangong station.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/this-screen-image-captured-at-beijing-aerospace-control-news-photo/1244869814?phrase=tiangong&adppopup=true">Xinhua News Agency via Getty Images</a></span>
</figcaption>
</figure>
<h2>Science and a steppingstone</h2>
<p>The main function of the Tiangong station is to perform <a href="https://www.youtube.com/watch?v=DAzoVdrppHs">research on life in space</a>. There is a particular focus on learning about the growth and development of different types of plants, animals and microorganisms, and there are more than <a href="https://doi.org/10.1038/d41586-022-03462-5">1,000 experiments planned for the next 10 years</a>. </p>
<p>Tiangong is strictly Chinese made and managed, but China has an open invitation for other nations to collaborate on experiments aboard Tiangong. So far, <a href="http://en.cmse.gov.cn/cooperationexchange/201906/t20190612_44777.html">nine projects from 17 countries have been selected</a>. </p>
<p>Although the new station is small compared to the <a href="https://www.engineering.com/story/battle-of-the-space-stations-iss-vs-tiangong">16 modules of the International Space Station</a>, Tiangong and the science done aboard will help <a href="https://www.space.com/china-five-year-plan-space-exploration-2022">support China’s future space missions</a>. In December 2023, China is planning to launch a new space telescope called Xuntian. This telescope will map stars and supermassive black holes among other projects with a resolution about the same as the Hubble Space Telescope but with a <a href="https://www.space.com/china-space-station-telescope-plans">wider view</a>. The telescope will periodically <a href="https://www.chinadaily.com.cn/a/202207/25/WS62ddd8d3a310fd2b29e6e14a.html">dock with the station</a> for maintenance.</p>
<p>China also has <a href="https://www.space.com/china-five-year-plan-space-exploration-2022">plans to launch multiple missions</a> to Mars and nearby comets and asteroids with the goal of bringing samples back to Earth. And perhaps most notably, China has announced plans to build a <a href="https://www.space.com/china-russia-moon-base-ilrs">joint Moon base</a> with Russia – though no timeline for this mission has been set. </p>
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<figcaption><span class="caption">The three-person crew of taikonauts greets the crew already aboard the Tiangong station in early December 2022.</span></figcaption>
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<h2>Astropolitics</h2>
<p>A new era in space is unfolding. The Tiangong station is beginning its life just as the International Space Station, after more than 30 years in orbit, is set to be <a href="https://www.theguardian.com/science/2022/feb/02/international-space-station-will-plummet-to-a-watery-grave-in-2030">decommissioned</a> by 2030. </p>
<p>The International Space Station is the classic example of collaborative ideals in space – even at the height of the Cold War, the U.S. and the Soviet Union came together to develop and launch the beginnings of the space station in the early 1990s. By comparison, China and the U.S. have not been so jovial in their orbital dealings.</p>
<p>In the 1990s, when China was still launching U.S. satellites into orbit, concerns emerged that China was <a href="https://hir.harvard.edu/trouble-in-the-stars-the-importance-of-us-china-bilateral-cooperation-in-space/">accidentally acquiring – or stealing – U.S. technology</a>. These concern in part led to the <a href="https://www.congress.gov/112/plaws/publ10/PLAW-112publ10.htm">Wolf Amendment</a>, passed by Congress in 2011, which prohibits NASA from collaborating with China in any capacity. China’s space program was not mature enough to be part of the construction of the International Space Station in the 1990s and early 2000s. By the time China had the ability to contribute to the International Space Station, the Wolf Amendment prevented it from doing so.</p>
<p>It remains to be seen how the map of space collaboration will change in the coming years. The U.S.-led <a href="https://www.nasa.gov/artemisprogram/">Artemis Program</a> that aims to build a self-sustaining habitat on the Moon is open to all nations, and <a href="https://www.state.gov/france-becomes-twentieth-nation-to-sign-the-artemis-accords/">19 countries have joined as partners</a> so far. China has also recently opened its joint Moon mission with Russia to other nations. This was partly driven by <a href="https://time.com/6218389/china-russia-moon-missions/">cooling Chinese-Russian relations</a> but also due to the fact that because of the war in Ukraine, Sweden, France and the European Space Agency canceled planned missions with Russia. </p>
<p>As tensions on Earth rise between China, Russia and the West, and some of that jockeying <a href="https://theconversation.com/space-blocs-the-future-of-international-cooperation-in-space-is-splitting-along-lines-of-power-on-earth-180221">spills over into space</a>, it remains to be seen how the decommissioning of the International Space Station and operation of the Tiangong station will influence the China-U.S. relationship.</p>
<p>An event like the famous handshake between U.S. astronauts and Russian cosmonauts while orbiting Earth in 1975 is a long way off, but collaboration between the U.S. and China could do much to cool tensions on and above the Earth.</p><img src="https://counter.theconversation.com/content/195882/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eytan Tepper owns exchange-traded funds (ETFs) that track the space sector (UFO and ARKX). He is a principal investigator (PI) on grants from the Social Sciences and Humanities Research Council of Canada, receives funding from Micas, and is a co-PI on grants from the Carnegie Corporation of New York. He is affiliated with the Centre for International Governance Innovation (CIGI), Laval University, and Western University.</span></em></p><p class="fine-print"><em><span>Scott Shackelford is a principal investigator on grants from the Hewlett Foundation, Carnegie Corporation of New York, National Science Foundation, and the Microsoft Corporation supporting both the Ostrom Workshop and the Indiana University Cybersecurity Clinic.</span></em></p>China has completed construction of the Tiangong space station, and science projects are now underway. The station is an important piece of China’s ambitious plans for space activity in coming years.Eytan Tepper, Visiting Assistant Professor of Space Governance, Indiana UniversityScott Shackelford, Professor of Business Law and Ethics, Indiana 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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Read more:
<a href="https://theconversation.com/australia-just-flew-its-own-vomit-comet-its-a-big-deal-for-zero-gravity-space-research-185601">Australia just flew its own 'vomit comet'. It's a big deal for zero-gravity space research</a>
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<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>
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<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/1866662022-07-25T17:18:45Z2022-07-25T17:18:45ZScientists calculate the risk of someone being killed by space junk<figure><img src="https://images.theconversation.com/files/475439/original/file-20220721-13094-8flfis.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4089%2C2152&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/space-debris-around-planet-earth-1943915647">Frame Stock Footage/Shutterstock</a></span></figcaption></figure><p>The chance of someone being killed by space junk falling from the sky may seem ridiculously tiny. After all, nobody has yet died from such an accident, though there have been instances of injury and damage to property. But given that we are launching an increasing number of satellites, rockets and probes into space, do we need to start taking the risk more seriously?</p>
<p>A new study, <a href="https://www.nature.com/articles/s41550-022-01718-8">published in Nature Astronomy</a>, has estimated the chance of causalities from falling rocket parts over the next ten years. </p>
<p>Every minute of every day, debris rains down on us from space – a hazard we are almost completely unaware of. The microscopic particles from asteroids and comets patter down through the atmosphere to settle unnoticed on the Earth’s surface – adding up to around 40,000 tonnes of dust each year.</p>
<p>While this is not a problem for us, such debris can do damage to spacecraft - as was recently <a href="https://arxiv.org/ftp/arxiv/papers/2207/2207.05632.pdf">reported for the James Webb space telescope</a>. Occasionally, a larger sample arrives as a <a href="https://theconversation.com/how-scientists-found-rare-fireball-meteorite-pieces-on-a-driveway-and-what-they-could-teach-us-156690">meteorite</a>, and maybe once every 100 years or so, a body tens of metres across manages to drive through the atmosphere to excavate a crater. </p>
<p>And – fortunately very rarely – <a href="https://theconversation.com/dont-look-up-several-asteroids-are-heading-towards-earth-heres-how-we-deal-with-threats-in-real-life-174512">kilometre-sized objects</a> can make it to the surface, causing death and destruction – as shown by the lack of dinosaurs roaming the Earth today. These are examples of natural space debris, the uncontrolled arrival of which is unpredictable and spread more or less evenly across the globe.</p>
<p>The new study, however, investigated the uncontrolled arrival of artificial space debris, such as spent rocket stages, associated with rocket launches and satellites. Using mathematical modelling of the inclinations and orbits of rocket parts in space and population density below them, as well as 30 years’ worth of past satellite data, the authors estimated where rocket debris and other pieces of space junk land when they fall back to Earth. </p>
<p>They found that there is a small, but significant, risk of parts re-entering in the coming decade. But this is more likely to happen over southern latitudes than northern ones. In fact, the study estimated that rocket bodies are approximately three times more likely to land at the latitudes of Jakarta in Indonesia, Dhaka in Bangladesh or Lagos in Nigeria than those of New York in the US, Beijing in China or Moscow in Russia.</p>
<p>The authors also calculated a “casualty expectation” — the risk to human life — over the next decade as a result of uncontrolled rocket re-entries. Assuming that each re-entry spreads lethal debris over an area of ten square metres, they found that there is a 10% chance of one or more casualties over the next decade, on average.</p>
<p>To date, the potential for debris from satellites and rockets to cause harm at the Earth’s surface (or in the atmosphere to air traffic) has been regarded as negligible. Most studies <a href="https://www.esa.int/Space_Safety/Space_Debris/The_current_state_of_space_debris#:%7E:text=%E2%80%9CThe%20biggest%20contributor%20to%20the,the%20number%20of%20such%20events">of such space debris</a> have focused on the risk generated in orbit by defunct satellites which might obstruct the safe operation of functioning satellites. Unused fuel and batteries also lead to explosions in orbit which generate additional waste. </p>
<p>But as the number of entries into the rocket launch business increases - and moves from government to private enterprise - it is highly likely that the number of accidents, both in space and on Earth, such as that which followed the launch of the <a href="https://www.space.com/chinese-rocket-booster-long-march-5b-space-junk-crash">Chinese Long March 5b</a>, will also increase. The new study warns that the 10% figure is therefore a conservative estimate.</p>
<h2>What can be done</h2>
<p>There are a range of technologies that make it entirely possible to control the re-entry of debris, but they are expensive to implement. For example, spacecraft can be “passivated”, whereby unused energy (such as fuel or batteries) is expended rather than stored once the lifetime of the spacecraft has ended. </p>
<p>The choice of orbit for a satellite can also reduce the chance of producing debris. A defunct satellite can be programmed to move into low Earth orbit, where it will burn up. </p>
<figure class="align-center ">
<img alt="Image of Saudi officials inspect a crashed module in January 2001." src="https://images.theconversation.com/files/475440/original/file-20220721-10058-au1ju6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/475440/original/file-20220721-10058-au1ju6.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/475440/original/file-20220721-10058-au1ju6.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/475440/original/file-20220721-10058-au1ju6.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/475440/original/file-20220721-10058-au1ju6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/475440/original/file-20220721-10058-au1ju6.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/475440/original/file-20220721-10058-au1ju6.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Saudi officials inspect a crashed module in January 2001.</span>
<span class="attribution"><span class="source">wikipedia</span></span>
</figcaption>
</figure>
<p>There are also attempts to launch re-usable rockets which, for example, <a href="https://www.spacex.com/">SpaceX</a> has demonstrated and <a href="https://www.blueorigin.com/new-glenn/">Blue Origin</a> is developing. These create a lot less debris, though there will be some from paint and metal shavings, as they return to Earth in a controlled way.</p>
<p>Many agencies do take the risks seriously. The European Space Agency is planning a mission to <a href="https://clearspace.today/">attempt the capture and removal of space debris</a> with a <a href="https://www.space.com/esa-startup-clearspace-debris-removal-2025">four-armed robot</a>. The UN, through its Office of Outer Space Affairs, issued a set of <a href="https://www.unoosa.org/pdf/publications/st_space_49E.pdf">Space Debris Mitigation Guidelines</a> in 2010, which was <a href="https://www.unoosa.org/res/oosadoc/data/documents/2018/aac_1052018crp/aac_1052018crp_20_0_html/AC105_2018_CRP20E.pdf">reinforced in 2018</a>. However, as the authors behind the new study point out, these are guidelines, not international law, and do not give specifics as to how mitigation activities should be implemented or controlled.</p>
<p>The study argues that advancing technologies and more thoughtful mission design would reduce the rate of uncontrolled re-entry of spacecraft debris, decreasing the hazard risk across the globe. It states that “uncontrolled rocket body reentries constitute a collective action problem; solutions exist, but every launching state must adopt them.”</p>
<p>A requirement for governments to act together is not unprecedented, as shown by the agreement to ban ozone layer-destroying chlorofluorcarbon chemicals. But, rather sadly, this kind of action usually requires a major event with significant consequences for the northern hemisphere before action is taken. And changes to international protocols and conventions take time.</p>
<p>In five years, it will be 70 years since the <a href="https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1957-001B#:%7E:text=Description,of%20the%20former%20Soviet%20Union.">launch of the first satellite</a> into space. It would be a fitting celebration of that event if it could be marked by a strengthened and mandatory international treaty on space debris, ratified by all UN states. Ultimately, all nations would benefit from such an agreement.</p><img src="https://counter.theconversation.com/content/186666/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Monica Grady receives funding from STFC and the UK Space Agency. As well as Professor of Planetary and Sapce Sciences at the Open University, she is Chancellor of Liverpool Hope University and a Senior Research Fellow at the Natural History Museum. Follow her on twitter @MonicaGrady</span></em></p>The southern hemisphere is more likely to be hit by space debris than the northern one.Monica Grady, Professor of Planetary and Space Sciences, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1846462022-06-09T03:39:24Z2022-06-09T03:39:24ZNASA to launch 3 rockets from Northern Territory in boost for Australian space efforts<figure><img src="https://images.theconversation.com/files/467899/original/file-20220609-17-nzafzf.jpeg?ixlib=rb-1.1.0&rect=0%2C0%2C5472%2C3645&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Equatorial Launch Australia</span></span></figcaption></figure><p>Over the next month, NASA will <a href="https://ela.space/ela-and-nasa-to-conduct-australias-first-ever-commercial-space-launch/">launch three rockets</a> from the Arnhem Space Centre in the Northern Territory on the Dhupuma Plateau, near Nhulunbuy. The rockets are 13 metre “sounding” rockets that will not reach orbit but will take scientific observations. </p>
<p>The launches represent a number of firsts for the Australian space industry. They also represent a major step forward for commercial space operators, as well as signalling the opportunity for future joint projects between Australia and the United States. </p>
<h2>The launches</h2>
<p>The Arnhem Space Centre is owned and operated by a commercial operator, Equatorial Launch Australia. It is located on the land of the Gumatj people, who as the traditional custodians of the land, have been consulted as part of the launch approval process.</p>
<p>Gumatj Corporation chair Djawa Yunupingu <a href="https://www.abc.net.au/news/2021-10-15/nt-nasa-arnhem-space-centre-ready-2022-take-off/100538796">told the ABC</a> last year the launch plans are “a step towards the future for our people”.</p>
<p>This is the first time NASA has conducted a rocket launch from a commercial facility outside the US. This involves a significant logistical undertaking, with each rocket delivered to the launch site <a href="https://www.abc.net.au/news/2022-06-08/nasa-launching-three-rockets-from-australia-northern-territory/101133750">via barge</a>. </p>
<p>More than <a href="https://www.spaceconnectonline.com.au/launch/5473-equatorial-launch-australia-inches-closer-to-nasa-rocket-blast-off">70 NASA personnel</a> will travel to the NT to support the launch and the scientific program.</p>
<p>The rockets have been designed and built by NASA and will be used for scientific investigations into the physics of the Sun, astrophysics and the type of planetary science we can only conduct in the southern hemisphere. After the launches, NASA <a href="https://www.abc.net.au/news/2022-06-08/nasa-launching-three-rockets-from-australia-northern-territory/101133750">says it will</a> clean up all material such as casing and payloads and return it to the US.</p>
<p>The NASA contract was first <a href="https://www.spaceconnectonline.com.au/launch/3435-ela-set-to-launch-nasa-sounding-rockets-from-nt-space-base">announced in 2019</a>. However, COVID lockdowns and travel restrictions have delayed the launches until now. </p>
<h2>What else is likely to be launched from this site?</h2>
<p>Equatorial Launch Australia also plans to construct a larger launch facility, with three launch pads, accommodating larger rockets and payloads. </p>
<p>Several more launches <a href="https://www.spaceconnectonline.com.au/launch/5475-ela-to-send-first-commercial-nasa-rocket-into-space-on-26-june">are planned</a> this year. The company is aiming to have 50 or more launches a year by 2024 and 2025.</p>
<h2>What does this mean for the future of the Australian space industry?</h2>
<p>The Arnhem Space Centre is one of three proposed commercial launch sites in Australia. </p>
<p>In September 2020 another operator, Southern Launch, conducted sub-orbital launches from its <a href="https://www.southernlaunch.space/koonibba-test-range">Koonibba Test Range</a> in South Australia, which is <a href="https://www.southernlaunch.space/koonibba-community">operated with</a> the Koonibba Community Aboriginal Corporation. </p>
<p>Southern Launch has also recently obtained a licence to operate its own commercial launch site, <a href="https://www.southernlaunch.space/wwolc">Whaler’s Way Orbital Launch Complex</a>, on the Eyre Peninsula. </p>
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Read more:
<a href="https://theconversation.com/3-2-1-liftoff-the-science-of-launching-rockets-from-australia-98307">3, 2, 1...liftoff! The science of launching rockets from Australia</a>
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<p>Gilmour Space Technologies <a href="https://www.abc.net.au/news/2021-10-24/gilmour-set-to-launch-bowen-rockets-from-2022/100562926">has applied for a licence</a> to undertake launches from Bowen in North Queensland. Its application is supported by the Queensland government and <a href="https://www.australiandefence.com.au/defence/cyber-space/traditional-owners-welcome-gilmour-space-s-new-launch-site">the Juru people</a>, who are the traditional owners of the land. The company plans to build and launch its own rockets from this site.</p>
<h2>Decades of disappointment</h2>
<p>The development of an Australian launch capability will be a big step for the country’s space industry. </p>
<p>In the 1960s, Australia’s launch facilities at Woomera in South Australia were used as part of the <a href="https://en.wikipedia.org/wiki/European_Launcher_Development_Organisation#Australian_downrange_tracker">European Launcher Development Organisation</a> (ELDO) project.</p>
<p>In 1967, Australia became the <a href="https://www.naa.gov.au/learn/learning-resources/learning-resource-themes/war/defence-equipment-and-weapons/launch-australias-first-satellite-documentary">fourth nation in the world</a> to launch a domestic-built satellite from its own territory. That satellite, the WRESAT, was launched from Woomera on an American Redstone rocket, and stayed in orbit until early 1968.</p>
<p>However, Australia lost interest in launching rockets when ELDO relocated to French Guiana.</p>
<p>In the early 1990s, an American company expressed interest in <a href="https://www.slq.qld.gov.au/blog/whatever-happened-cape-york-spaceport">building a launch facility</a> in Australia. However, those plans never materialised. </p>
<h2>Onwards and upwards</h2>
<p>In recent years, Australia’s interest in space science has been returning. However, even when the Australian Space Agency was created in 2018 there was <a href="https://theconversation.com/no-launch-from-australia-something-missing-from-our-plans-for-the-new-space-race-97924">some doubt</a> over whether we would be able to carry out our own launches.</p>
<p>These latest developments make it clear we will. Prime Minister Anthony Albanese <a href="https://www.pm.gov.au/media/nasa-go-launch-northern-territory">described</a> the launches as a project to “bring together global and local industry to take Australia’s space sector into a new era”.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/no-launch-from-australia-something-missing-from-our-plans-for-the-new-space-race-97924">No launch from Australia: something missing from our plans for the new space race</a>
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<p>Australia has also signed the <a href="https://www.nasa.gov/specials/artemis-accords/index.html">Artemis Accords</a>, joining the Artemis program to return humans to the Moon and on to Mars. The Artemis Accords were developed by NASA as “a shared vision for principles, grounded in the Outer Space Treaty of 1967, to create a safe and transparent environment which facilitates exploration, science, and commercial activities for all of humanity to enjoy”. </p>
<p>Enrico Palermo, Head of the Australian Space Agency, <a href="https://www.minister.industry.gov.au/ministers/husic/media-releases/nasa-go-launch-northern-territory">said</a> the Northern Territory launch would “further cement our reputation as a nation that global space players want to do business with”. </p>
<p>With new businesses and jobs at stake, this is an important move forward for Australia’s re-emergence as a serious space operator.</p><img src="https://counter.theconversation.com/content/184646/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Melissa de Zwart is Deputy Chair of the Space Industry Association of Australia. </span></em></p>Australia may soon have three commercial space launch facilitiesMelissa de Zwart, Professor (Digital Technology, Security and Governance), Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1785572022-03-10T11:43:28Z2022-03-10T11:43:28ZUkraine war: how it could play out in space – with potentially dangerous consequences<figure><img src="https://images.theconversation.com/files/450899/original/file-20220309-30-5zyxkc.jpeg?ixlib=rb-1.1.0&rect=42%2C21%2C2002%2C1339&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Could Russia crash the ISS?</span> <span class="attribution"><span class="source">NASA</span></span></figcaption></figure><p>Nearly three decades of close collaboration in space between Russia and the western world seems to be coming to an end. With increasing tensions over Vladimir Putin’s invasion of Ukraine, Russia has <a href="https://www.theverge.com/2022/2/25/22950498/russia-nasa-international-space-station-dmitry-rogozin-roscosmos-ukraine-iss">arguably threatened</a> to crash the International Space Station and refuse to launch satellites for western countries. A few months ago, Russia <a href="https://theconversation.com/russias-attack-on-its-own-satellite-is-reckless-and-endangers-us-all-172105">blew up one of its own defunct satellites</a>, creating space junk that threatened the safety of astronauts at the ISS.</p>
<p>So how is the war likely to impact on operations in space going forward, and what are the consequences? </p>
<p>Aggression in space could directly affect boots on the grounds. Imagery from space has become a regular feature in coverage of the invasion of Ukraine, showing long columns of armour moving inexorably towards Kyiv or Kharkiv. </p>
<p>While chilling in its content, it has offered a boost to the embattled Ukrainian resistance by helping it work out where the enemy is, where it is coming from and how it is configured. It is also a demonstration to the world of the level of force used by Russia, laid bare for all to see.</p>
<p>Satellite imagery used to be the preserve of advanced militaries and very few countries. Today, however, commercial companies are increasingly capturing such imagery, and their combined capability may surpass that of the Russian military. The advantage of this is that these companies can provide quasi-military support, potentially avoiding the tripwire of military involvement in Ukraine by western nations. </p>
<p>There are some who warn of a <a href="https://www.govinfo.gov/content/pkg/CHRG-114hhrg22564/html/CHRG-114hhrg22564.htm">decline in US space power</a>, particularly in the face of a highly ambitious Chinese space agenda and provocative Russian manoeuvres in space. But any estimation of space power must include the commercial sector, in which western companies, and American firms in particular, have a vast lead.</p>
<p>SpaceX provides not only satellite imagery, but also communications. Its founder, Elon Musk, <a href="https://twitter.com/FedorovMykhailo/status/1498392515262746630">has come to the aid</a> of Ukraine by providing it with terminals that allow access to the Starlink system, a megaconstellation of satellites that offers high-speed internet access. If Russia cuts off internet services and other forms of communication in Ukraine, Starlink could provide connectivity, giving Ukrainians secure to information and networking. </p>
<p>This is not wholly without risk, however. Musk has recently cautioned Ukrainian users that the Starlink terminals – effectively two-way satellite dishes - may allow them to be identified. </p>
<p>There have also been reports of Russia <a href="https://breakingdefense.com/2022/03/local-russian-gps-jamming-in-ukraine-hasnt-affected-us-support-ops-so-far/">jamming the GPS signal</a> from satellites in space to Ukraine. And it has been reported that Russia <a href="https://www.gpsworld.com/russia-expected-to-ditch-glonass-for-loran-in-ukraine-invasion/#:%7E:text=Russia%20expected%20to%20ditch%20GLONASS%20for%20Loran%20in%20Ukraine%20invasion,-February%2017%2C%202022&text=Russian%20forces%20are%20expert%20at,available%20once%20a%20battle%20begins.">fully expects</a> their own <a href="https://www.glonass-iac.ru/en/about_glonass/">GLONASS satellite positioning system</a> to be jammed as well. </p>
<p>If that happens, it will use an older, terrestrial system called Chayka, based on an older radio technology. While not as accurate as a satellite system, it should nevertheless be good enough for many of their purposes.</p>
<h2>Direct dangers?</h2>
<p>The conflict has also unfolded in other, unexpected ways in the space domain. In a <a href="https://twitter.com/Rogozin/status/1496933832905404422">series of tweets</a>, the director general of Russia’s space agency Roscosmos, Dmitry Rogozin, warned that ending cooperation over the ISS could lead to it falling out of orbit, possibly onto the United States or Europe (or China or India) – which has been interpreted <a href="https://www.independent.co.uk/tech/elon-musk-spacex-russia-iss-b2024749.html">as a threat</a>. </p>
<p>He noted that Russias’ <a href="https://www.nasa.gov/mission_pages/station/structure/elements/progress.html">Progress cargo ships</a> which provides the thrust to correct the orbit of the ISS. Without them, the space station would fall into the Earth’s atmosphere where most of it would burn up, yet some bits could survive and may hit people or buildings on Earth.</p>
<p>While this is extremely unlikely, not least due to the fact that there are Russian cosmonauts aboard currently, it was an alarming statement. In response, Musk said that his company <a href="https://twitter.com/elonmusk/status/1497370602075734021?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1497370602075734021%7Ctwgr%5E%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fpublish.twitter.com%2F%3Fquery%3Dhttps3A2F2Ftwitter.com2Felonmusk2Fstatus2F1497370602075734021widget%3DTweet">would assist</a> if Russia withdrew its support in a way that endangered the space station. </p>
<p>SpaceX’s <a href="https://theconversation.com/spacex-astronaut-launch-heres-the-rocket-science-139398">Dragon capsule</a> is currently the only other spacecraft capable of docking with and supplying the ISS, and so could also provide the thrust if needed. Either way, it signals a much less cooperative future in space, with the ISS <a href="https://theconversation.com/international-space-station-how-nasa-plans-to-destroy-it-and-the-dangers-involved-177374">being decommissioned soon</a> and Russia and China <a href="https://theconversation.com/artemis-accords-why-many-countries-are-refusing-to-sign-moon-exploration-agreement-148134">refusing to join</a> the US-led Artemis programme aiming to launch people to the Moon.</p>
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<p>Russia has also <a href="https://www.wsj.com/livecoverage/russia-ukraine-latest-news-2022-03-03/card/russia-halts-rocket-engine-deliveries-to-u-s--cXv7UBKAVZVCkeoZ6Iiy">halted its sales of rocket engines</a> to the US (though the US had banned the import of these some years ago) and is refusing to launch a batch of 36 OneWeb satellites, which are designed to provide satellite internet broadband services worldwide, unless the UK government divests itself of its share of the OneWeb programme, guaranteeing that they will not be used for military purposes. The UK has so far <a href="https://twitter.com/KwasiKwarteng/status/1499054094769664005">refused to negotiate</a>. OneWeb already has 428 of its planned 648 strong constellation in orbit, and may start looking elsewhere for launch support in the future, as will many other companies. </p>
<p>Many countries also still rely on Russia and its <a href="https://www.esa.int/Enabling_Support/Space_Transportation/Launch_vehicles/The_Russian_Soyuz_spacecraft">Soyuz rockets</a> for a number of launches for various applications, creating a difficult problem. But SpaceX and other companies, and indeed other countries, are increasingly able to plug the gap, so this is likely to be temporary.</p>
<p>If competition continues, it is not inconceivable that it could lead to conflict. While the use of kinetic weapons, which destroy satellites by running into them at high speeds and which <a href="https://theconversation.com/russian-anti-satellite-weapon-test-what-happened-and-what-are-the-risks-172016#:%7E:text=The%20one%20that%20Russia%20just,into%20them%20at%20high%20speeds.">Russia tested recently</a>, seems unthinkable, we cannot be sure what Putin will do next. </p>
<p>The use of such weapons could create increased space junk which could destroy satellites and other probes in space, or even rain down on Earth. So it’s important that the hostile threats in the space domain are not be allowed to escalate into anything further.</p>
<p>While Russia has a great deal of expertise in the space domain, its power there faces clear limits. Empty threats and tarnishing its reliability as a launch provider will only undermine its future prospects. </p>
<p>But more importantly, western commercial space assets have provided an important element of support for the besieged Ukrainians. This will enable important data and imagery to flow to where it is needed, to military units, decision-makers and to the population more broadly. Given the number and variety of satellites flying overhead, Russia will find it very difficult to respond.</p><img src="https://counter.theconversation.com/content/178557/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Hilborne receives funding from Economic and Social Research Council (ESRC) </span></em></p>From harming satellites to crashing the ISS, the Ukraine war could soon extend to space.Mark Hilborne, Lecturer of Defence Studies, King's College LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1770232022-03-01T13:37:02Z2022-03-01T13:37:02ZAn asteroid impact could wipe out an entire city – a space security expert explains NASA’s plans to prevent a potential catastrophe<figure><img src="https://images.theconversation.com/files/447109/original/file-20220217-25-11g19ha.jpg?ixlib=rb-1.1.0&rect=0%2C158%2C5097%2C3275&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A giant asteroid struck Earth and wiped out the dinosaurs 65 million years ago. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/chicxulub-asteroid-impact-royalty-free-illustration/713781277?adppopup=true">Mark Garlick/Science Photo Library via Getty Images</a></span></figcaption></figure><p>The Earth exists in a dangerous environment. Cosmic bodies, like asteroids and comets, are constantly zooming through space and often crash into our planet. Most of these are too small to pose a threat, but some can be <a href="https://www.nytimes.com/2007/03/16/opinion/16iht-edschweick.4929643.html">cause for concern</a>.</p>
<p>As a scholar who <a href="https://svetlabenitzhak.com/2017/07/10/about/">studies space and international security</a>, it is my job to ask what the likelihood of an object crashing into the planet really is – and whether governments are spending enough money to prevent such an event.</p>
<p>To find the answers to these questions, one has to know what near-Earth objects are out there. To date, NASA has tracked only an estimated <a href="https://www.nasa.gov/planetarydefense/faq">40% of the bigger ones</a>. Surprise asteroids have visited Earth in the past and will undoubtedly do so in the future. When they do appear, how prepared will humanity be?</p>
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<a href="https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing thousands of blue orbits overlapping with Earth's own orbit." src="https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=511&fit=crop&dpr=1 600w, https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=511&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=511&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=643&fit=crop&dpr=1 754w, https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=643&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/447112/original/file-20220217-1111-ukmxoy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=643&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 orbits of thousands of asteroids (in blue) cross paths with the orbits of planets (in white), including Earth’s.</span>
<span class="attribution"><a class="source" href="https://apod.nasa.gov/apod/ap210829.html">NASA/JPL</a></span>
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<h2>The threat from asteroids and comets</h2>
<p>Millions of objects of various sizes orbit the Sun. Near-Earth objects include asteroids and comets whose orbits will bring them <a href="https://cneos.jpl.nasa.gov/about/neo_groups.html">within 120 million miles</a> (193 million kilometers) of the Sun.</p>
<p>Astronomers consider a near-Earth object a threat if it will <a href="https://cneos.jpl.nasa.gov/about/neo_groups.html">come within 4.6 million miles</a> (7.4 million km) of the planet and is at least 460 feet (140 meters) in diameter. If a celestial body of this size crashed into Earth, it could destroy an entire city and cause extreme regional devastation. Larger objects - 0.6 miles (1 km) or more - could have global effects and even cause mass extinctions.</p>
<p>The most famous and destructive impact took place 65 million years ago when a 6-mile (10-km) diameter <a href="https://press.princeton.edu/books/paperback/9780691169668/t-rex-and-the-crater-of-doom">asteroid crashed into what is now the Yucatán Peninsula</a>. It <a href="https://doi.org/10.1126/science.1177265">wiped out most plant and animal species</a> on Earth, including the dinosaurs.</p>
<p>But smaller objects can also cause significant damage. In 1908, an approximately 164-foot (50-meter) celestial body exploded over the <a href="https://www.sciencedirect.com/science/article/abs/pii/S0019103518305104?via%3Dihub">Tunguska</a> river in Siberia. It <a href="https://www.cbc.ca/news/science/the-tunguska-event-1.742329">leveled</a> more than 80 million trees over 830 square miles (2,100 square km). In 2013, an asteroid only 65 feet (20 meters) across burst in the atmosphere 20 miles (32 km) above Chelyabinsk, Russia. It released the equivalent of 30 Hiroshima bombs worth of energy, <a href="https://doi.org/10.1126/science.1242642">injured over 1,100 people</a> and caused US$33 million in damage.</p>
<p>The next asteroid of substantial size to potentially hit Earth is asteroid 2005 ED224. When the 164-foot (50-meter) asteroid passes by on March 11, 2023, there is roughly a <a href="https://cneos.jpl.nasa.gov/sentry/details.html#?des=2005%20ED224">1 in 500,000 chance of impact</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graph showing the number of known large, medium and small near-Earth objects." src="https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/447113/original/file-20220217-25-4n6zxf.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">NASA has been steadily finding and tracking near-Earth objects since the 1990s.</span>
<span class="attribution"><a class="source" href="https://cneos.jpl.nasa.gov/stats/totals.html">NASA/JPL-Caltech</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Watching the skies</h2>
<p>While the <a href="https://trumpwhitehouse.archives.gov/wp-content/uploads/2021/01/NEO-Impact-Threat-Protocols-Jan2021.pdf">chances of a larger cosmic body impacting Earth are small</a>, the devastation <a href="http://mpainesyd.com/idisk/Public/rocks_from_space/chapman4oecd.pdf">would be enormous</a>.</p>
<p>Congress recognized this threat, and in <a href="https://archive.org/details/nasa_techdoc_19920025001">the 1998 Spaceguard Survey</a>, it tasked NASA to find and track 90% of near-Earth objects 0.6 miles (1 km) across or bigger within 10 years. NASA <a href="https://www.nasa.gov/mission_pages/WISE/multimedia/gallery/neowise/pia14734.html">surpassed the 90% goal</a> in 2011. </p>
<p>In 2005, <a href="https://www.govinfo.gov/content/pkg/STATUTE-119/pdf/STATUTE-119-Pg2895.pdf">Congress passed another bill</a> requiring NASA to expand its search and track at least 90% of all near-Earth objects 460 feet (140 meters) or larger by the end of 2020. That year has come and gone and, mostly due to <a href="https://www.nap.edu/catalog/12842/defending-planet-earth-near-earth-object-surveys-and-hazard-mitigation">a lack of financial resources</a>, only <a href="https://www.nasa.gov/planetarydefense/faq">40% of those objects have been mapped</a>. </p>
<p>As of Feb. 14, 2022, <a href="https://cneos.jpl.nasa.gov/stats/totals.html">astronomers have located 28,266</a> near-Earth asteroids, of which 10,033 are 460 feet (140 meters) or larger in diameter and 888 at least 0.6 miles (1 km) across. About <a href="https://www.nasa.gov/planetarydefense/faq">30 new objects</a> are added each week.</p>
<p>A new mission, <a href="https://www.congress.gov/bill/115th-congress/house-bill/5503/text#toc-HB5A37F19BF1E40DC8CF66F29EAE2DD66">funded by Congress in 2018</a>, is scheduled to launch in 2026 an infrared, <a href="https://www.nasa.gov/feature/nasa-approves-asteroid-hunting-space-telescope-to-continue-development">space-based telescope</a> – NEO Surveyor – dedicated to <a href="https://neos.arizona.edu/">searching for potentially dangerous asteroids</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Yl2f46L5DJ4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Smaller asteroids, like the one that exploded over Russia in 2013, can strike Earth without warning, but larger, more dangerous objects have surprised astronomers, too.</span></figcaption>
</figure>
<h2>Cosmic surprises</h2>
<p>We can only prevent a disaster if we know it is coming, and asteroids have sneaked up on Earth before. </p>
<p>An asteroid the size of a football field – dubbed the “City-killer” – passed <a href="https://www.washingtonpost.com/nation/2019/07/26/it-snuck-up-us-city-killer-asteroid-just-missed-earth-scientists-almost-didnt-detect-it-time/">less than 45,000 miles</a> from Earth in 2019. An asteroid the size of a 747 jet <a href="https://www.jpost.com/science/747-sized-asteroid-skimmed-by-earth-and-scientists-didnt-see-it-coming-680052">came close</a> in 2021 as did a 0.6-mile (1-km) wide <a href="https://www.space.com/16263-asteroid-2012lz1-size-earth-flyby.html">asteroid</a> in 2012. Each of these was discovered only <a href="https://www.esa.int/Safety_Security/Asteroid_s_surprise_close_approach_illustrates_need_for_more_eyes_on_the_sky">about a day</a> before they passed Earth. </p>
<p>Research suggests that one reason may be that Earth’s rotation <a href="https://doi.org/10.1016/j.icarus.2021.114735">creates a blind spot</a> whereby some asteroids remain undetected or appear stationary. This may be a problem, as some surprise asteroids do not miss us. In 2008, astronomers spotted a small <a href="https://cneos.jpl.nasa.gov/news/2008tc3.html">asteroid</a> only 19 hours before it crashed into rural Sudan. And the recent <a href="https://www.sciencealert.com/astronomers-have-discovered-a-surprise-asteroid-orbiting-between-mercury-and-venus">discovery</a> of an asteroid 1.2 miles (2 km) in diameter suggests that there are still big objects lurking.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A drawing of a spacecraft approaching two asteroids." src="https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/447115/original/file-20220217-15-mq01h6.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">NASA’s DART mission will crash a small spacecraft into the double asteroid Didymos to see if it will change the asteroid’s orbit.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/image-feature/stay-tuned-for-dart">NASA/JHUAPL/Steve Gribben</a></span>
</figcaption>
</figure>
<h2>What can be done?</h2>
<p>To protect the planet from cosmic dangers, early detection is key. At the 2021 Planetary Defense Conference, scientists recommended a minimum of <a href="https://www.businessinsider.com/nasa-asteroid-simulation-reveals-need-years-of-warning-2021-5">five to 10 years’ preparation time</a> to mount a successful defense against hazardous asteroids. </p>
<p>If astronomers find a dangerous object, there are <a href="https://www.nap.edu/catalog/12842/defending-planet-earth-near-earth-object-surveys-and-hazard-mitigation">four ways</a> to mitigate a disaster. The first involves regional first-aid and evacuation measures. A second approach would involve sending a spacecraft to fly near a small- or medium-sized asteroid; the gravity of the craft would slowly change the object’s orbit. To <a href="https://www.nap.edu/catalog/12842/defending-planet-earth-near-earth-object-surveys-and-hazard-mitigation">change a bigger asteroid’s path</a>, we can either crash something into it at high speeds or detonate a nuclear warhead nearby.</p>
<p>These may seem like far-fetched ideas, but in November 2021, NASA launched the world’s first full-scale planetary defense mission as a proof of concept: the <a href="https://www.nasa.gov/planetarydefense/dart">Double Asteroid Redirection Test</a>, or DART. The <a href="https://solarsystem.nasa.gov/asteroids-comets-and-meteors/asteroids/didymos/in-depth/">large asteroid Didymos</a> and its small moon currently pose no threat to Earth. In September 2022, NASA plans to change the asteroid’s orbit by crashing a 1,340-pound (610 kg) probe into Didymos’ moon at a speed of approximately 14,000 mph (22,500 kph). </p>
<p>Learning more about what threatening asteroids are made of is also important, as their composition may affect how successful we are at deflecting them. The <a href="https://www.nasa.gov/feature/goddard/2020/bennu-top-ten">asteroid Bennu</a> is 1,620 feet (490 meters) in diameter. Its orbit will bring it dangerously close to Earth on Sept. 24, 2182, and there is a <a href="https://cneos.jpl.nasa.gov/sentry/details.html#?des=101955">1 in 2,700</a> chance of a collision. An asteroid of this size could wipe out an entire continent, so to learn more about Bennu, NASA launched the <a href="https://www.nasa.gov/osiris-rex">OSIRIS-Rex</a> probe in 2016. The spacecraft arrived at Bennu, took pictures, collected samples and is due to return to Earth in 2023. </p>
<p>[<em>Get the best of The Conversation, every weekend.</em> <a href="https://memberservices.theconversation.com/newsletters/?nl=weekly&source=inline-weeklybest">Sign up for our weekly newsletter</a>.]</p>
<h2>Spending on planetary defense</h2>
<p>In 2021, NASA’s planetary defense budget was <a href="https://www.nasa.gov/sites/default/files/atoms/files/updated_fy_2021_spend_plan_june_2021.pdf">$158 million</a>. This is just <a href="https://www.planetary.org/articles/nasas-planetary-defense-budget-growth">0.7%</a> of NASA’s <a href="https://www.nasa.gov/sites/default/files/atoms/files/fy2022_budget_summary.pdf">total budget</a> and just 0.02% of the roughly <a href="https://www.defense.gov/Spotlights/FY2021-Defense-Budget/">$700 billion 2021 U.S. defense budget</a>.</p>
<p>This budget supports a number of missions, including the NEO Surveyor at <a href="https://docs.google.com/spreadsheets/d/e/2PACX-1vSngWs2AJa9KoPByrpX-XUgqD6UcMdjl3IW1xAW-m3yCvjreNM6d9KFWkshhxE_sPW9JmgmsaV0NwbG/pubhtml">$83 million</a>, DART at <a href="https://www.planetary.org/space-policy/cost-of-dart">$324 million</a> and Osiris Rex at around <a href="https://www.planetary.org/space-policy/cost-of-osiris-rex">$1 billion</a> over several years.</p>
<p>Is this the right amount to invest in monitoring the skies, given the fact that some <a href="https://www.nasa.gov/planetarydefense/faq">60% of all potentially dangerous asteroids remain undetected</a>? This is an important question to ask when one considers the potential consequences.</p>
<p>Investing in planetary defense is akin to buying homeowners insurance. The likelihood of experiencing an event that destroys your house is very small, yet people buy insurance nonetheless.</p>
<p>If even a single object larger than 460 feet (140 meters) hits the planet, the devastation and loss of life would be extreme. A bigger impact could quite literally wipe out most species on Earth. Even if no such body is expected to hit Earth in the <a href="https://www.smithsonianmag.com/science-nature/the-very-real-effort-to-track-killer-asteroids-and-comets-180979206/">next 100 years</a>, the chance is not zero. In this low likelihood versus high consequences scenario, investing in protecting the planet from dangerous cosmic objects may give humanity some peace of mind and could prevent a catastrophe.</p><img src="https://counter.theconversation.com/content/177023/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The views expressed are those of the author and do not reflect the official position of the U.S. Department of Defense, or of any organization the author is affiliated with, including the Air University, Air War College, the U.S. Air Force and the U.S. Space Force.</span></em></p>NASA has only mapped 40% of the potentially dangerous asteroids that could crash into Earth. New projects will boost that number, and upcoming missions will test tech that could prevent collisions.Svetla Ben-Itzhak, Assistant Professor of Space and International Relations, West Space Seminar, Air War College, Air UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1708492021-11-15T13:11:18Z2021-11-15T13:11:18ZHave we made an object that could travel 1% the speed of light?<figure><img src="https://images.theconversation.com/files/429624/original/file-20211101-21-hweqmz.jpg?ixlib=rb-1.1.0&rect=389%2C463%2C8635%2C3891&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">It only takes light about eight minutes to go from the Sun to Earth.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/sunrise-in-space-royalty-free-image/174578300?adppopup=true"> loops7/E+ via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>Have we made an object that could travel at at least 1% the speed of light? – Anadi, age 14, Jammu and Kashmir, India</strong></p>
</blockquote>
<hr>
<p><a href="https://www.universetoday.com/38040/speed-of-light-2/">Light is fast</a>. In fact, it is the fastest thing that exists, and a law of the universe is that nothing can move faster than light. Light travels at 186,000 miles per second (300,000 kilometers per second) and can go from the Earth to the Moon in just over a second. Light can streak from Los Angeles to New York in less than the blink of an eye.</p>
<p>While 1% of anything doesn’t sound like much, with light, that’s still really fast – close to 7 million miles per hour! At 1% the speed of light, it would take a little over a second to get from Los Angeles to New York. This is more than 10,000 times faster than a commercial jet.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A spacecraft with the sun in the background." src="https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=415&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=415&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=415&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=522&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=522&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429627/original/file-20211101-25-c3f9c9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=522&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 Parker Solar Probe, seen here in an artist’s rendition, is the fastest object ever made by humans and used the gravity of the Sun to get going 0.05% the speed of light.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Parker_Solar_Probe.jpg">NASA/Johns Hopkins APL/Steve Gribben</a></span>
</figcaption>
</figure>
<h2>The fastest things ever made</h2>
<p><a href="https://hypertextbook.com/facts/1999/MariaPereyra.shtml">Bullets</a> can go 2,600 mph (4,200 kmh), more than three times the speed of sound. The fastest aircraft is NASA’s <a href="https://www.wearethemighty.com/tech/the-8-fastest-man-made-objects-ever/">X3 jet plane</a>, with a top speed of 7,000 mph (11,200 kph). That sounds impressive, but it’s still only 0.001% the speed of light.</p>
<p>The fastest human-made objects are spacecraft. They use rockets to break free of the Earth’s gravity, which takes a speed of 25,000 mph (40,000 kmh). The spacecraft that is traveling the fastest is NASA’s <a href="https://www.cnet.com/home/energy-and-utilities/nasa-solar-probe-becomes-fastest-object-ever-built-as-it-touches-the-sun/">Parker Solar Probe</a>. After it launched from Earth in 2018, it skimmed the Sun’s scorching atmosphere and used the Sun’s gravity to reach 330,000 mph (535,000 kmh). That’s blindingly fast – yet only 0.05% of the speed of light.</p>
<h2>Why even 1% of light speed is hard</h2>
<p>What’s holding humanity back from reaching 1% of the speed of light? In a word, energy. Any object that’s moving has energy due to its motion. Physicists call this kinetic energy. To go faster, you need to increase kinetic energy. The problem is that it takes a lot of <a href="https://www.omnicalculator.com/physics/relativistic-ke">kinetic energy</a> to increase speed. To make something go twice as fast takes four times the energy. Making something go three times as fast requires nine times the energy, and so on. </p>
<p>For example, to get a teenager who weighs 110 pounds (50 kilograms) to 1% of the speed of light would cost 200 trillion Joules (a measurement of energy). That’s roughly the same amount of energy that 2 million people in the U.S. use in a day.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A shiny golden-hued square with a small spacecraft attached in space with a planet in the background." src="https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429630/original/file-20211101-21-5bh2wr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Solar sails, the thin shiny square seen in this artist’s rendition of the Japanese IKAROS spacecraft, could propel a spacecraft to 10% the speed of light.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:IKAROS_solar_sail.jpg#/media/File:IKAROS_solar_sail.jpg">Andrzej Mirecki via Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>How fast can we go?</h2>
<p>It’s possible to get something to 1% the speed of light, but it would just take an enormous amount of energy. Could humans make something go even faster?</p>
<p>Yes! But engineers need to figure out new ways to make things move in space. All rockets, even the sleek new rockets used by SpaceX and Blue Origins, <a href="https://www.sciencelearn.org.nz/resources/393-types-of-chemical-rocket-engines">burn rocket fuel</a> that isn’t very different from gasoline in a car. The problem is that burning fuel is very inefficient. </p>
<p>Other methods for pushing a spacecraft involve using <a href="https://www.nasa.gov/feature/glenn/2020/the-propulsion-we-re-supplying-it-s-electrifying">electric or magnetic forces</a>. <a href="https://www.nasa.gov/directorates/spacetech/niac/2012_Phase_II_fusion_driven_rocket/">Nuclear fusion</a>, the process that powers the Sun, is also much more efficient than chemical fuel. </p>
<p>Scientists are researching many other ways to go fast – even <a href="https://theconversation.com/warp-drives-physicists-give-chances-of-faster-than-light-space-travel-a-boost-157391">warp drives</a>, the faster-than-light travel popularized by Star Trek. </p>
<p>One promising way to get something moving very fast is to use a solar sail. These are large, thin sheets of plastic attached to a spacecraft and designed so that sunlight can push on them, like wind in a normal sail. A few spacecraft have used solar sails to show that they work, and scientists think that a solar sail could <a href="http://ffden-2.phys.uaf.edu/webproj/212_spring_2015/Robert_Miller/physics.html#:%7E:text=Solar%20sails%20have%20a%20maximum,the%20sail%20propelling%20it%20forward">propel spacecraft to 10% of the speed of light</a>. </p>
<p>One day, when humanity is not limited to a tiny fraction of the speed of light, we might <a href="https://tauzero.aero/">travel to the stars</a>.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/170849/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Impey receives funding from the National Science Foundation and the Hearst Foundation.</span></em></p>The fastest things ever made by humans are spacecraft, and the fastest spacecraft reached 330,000 mph – only 0.05% the speed of light. But there are ways to go faster.Chris Impey, University Distinguished Professor of Astronomy, University of ArizonaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1698052021-11-01T12:26:16Z2021-11-01T12:26:16ZA small telescope past Saturn could solve some mysteries of the universe better than giant telescopes near Earth<figure><img src="https://images.theconversation.com/files/429193/original/file-20211028-27-1f4qlx4.png?ixlib=rb-1.1.0&rect=0%2C186%2C2592%2C1593&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A telescope in the outer solar system would be able to do unique science that is impossible closer to the Sun.</span> <span class="attribution"><span class="source">Michael Zemcov</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Dozens of space-based telescopes operate near Earth and provide incredible images of the universe. But imagine a telescope far away in the outer solar system, 10 or even 100 times farther from the Sun than Earth. The ability to look back at our solar system or peer into the darkness of the distant cosmos would make this a uniquely powerful scientific tool.</p>
<p><a href="https://www.rit.edu/directory/mbzsps-michael-zemcov">I’m an astrophysicist</a> who studies the formation of structure in the universe. Since the 1960s, scientists like me have been considering the important scientific questions we might be able to answer with a telescope placed in the outer solar system. </p>
<p>So what would such a mission look like? And what science could be done?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing the Sun and all planets in a line." src="https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=227&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=227&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=227&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=286&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=286&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429160/original/file-20211028-25-3re5m6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=286&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Where a telescope is located matters nearly as much as its power. In many cases, the farther from the Sun, the better.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Solar-System-blank.jpg#/media/File:Solar-System-blank.jpg">Beinahegut/WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>A tiny telescope far from home</h2>
<p>The scientific strength of a telescope far from Earth would come primarily from its location, not its size. Plans for a telescope in the outer solar system would put it somewhere beyond the orbit of Saturn, roughly a billion or more miles from Earth. </p>
<p>We’d need only send a very small telescope – with a lens roughly the size of a small plate – to achieve some truly unique astrophysical insights. Such a telescope could be built to weigh less than 20 pounds (9 kilograms) and could be piggybacked on virtually any <a href="https://interstellarprobe.jhuapl.edu">mission to Saturn or beyond</a>. </p>
<p>Though small and simple compared with telescopes like <a href="https://hubblesite.org">Hubble</a> or <a href="https://www.jwst.nasa.gov/content/webbLaunch/index.html">James Webb</a>, such an instrument operating away from the bright light of the Sun could <a href="https://arxiv.org/pdf/1903.05729.pdf">make measurements</a> that are difficult or <a href="https://arxiv.org/pdf/1802.09536.pdf">outright impossible from a vantage point near the Earth</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A picture and graphic showing a disc of dust around a central star." src="https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=302&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=302&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=302&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=379&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=379&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429192/original/file-20211028-13-1wgvq9a.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=379&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 Sun has a disc of dust and gas surrounding it, much like the pinkish haze seen in this image and graphical representation of a nearby red dwarf star and its dust cloud.</span>
<span class="attribution"><a class="source" href="https://hubblesite.org/contents/media/images/2013/20/3181-Image.html?news=true">NASA/ESA/J. Debes</a></span>
</figcaption>
</figure>
<h2>Outside looking in</h2>
<p>Unfortunately for astronomers, getting a selfie of the solar system is a challenge. But being able to see the solar system from an outside vantage point would reveal a lot of information, in particular about the shape, distribution and composition of the dust cloud that surrounds the Sun. </p>
<p>Imagine a street lamp on a foggy evening – by standing far away from the lamp, the swirling mists are visible in a way that someone <a href="https://doi.org/10.3847/25c2cfeb.2f064292">standing under the streetlight could never see</a>.</p>
<p>For years astrophysicists have been able to take images of and study the dust discs in solar systems <a href="https://roman.gsfc.nasa.gov/science/Astro2020/ChenChristineH.pdf?version=1&modificationDate=1628623860142&api=v2">around other stars in the Milky Way</a>. But these stars are very far away, and there are <a href="https://www.science.org/content/article/cosmic-conundrum-disks-gas-and-dust-supposedly-form-planets-don-t-seem-have-goods">limits to what astronomers can learn about them</a>. Using observations looking back toward the Sun, astronomers could compare the shape, features and composition of these distant dust clouds with detailed data on Earth’s own solar system. This data would fill gaps in knowledge about solar dust clouds and make it possible to understand the history of production, migration and destruction of dust in other solar systems that there is no hope of traveling to in person.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A picture of thousands of galaxies." src="https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429164/original/file-20211028-20-129axtv.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The universe is full of galaxies – as seen in this image called the Hubble Ultra Deep Field – and measuring the cumulative light from these is hard to do from Earth.</span>
<span class="attribution"><a class="source" href="https://svs.gsfc.nasa.gov/30946">NASA/JPL</a></span>
</figcaption>
</figure>
<h2>Deep darkness of space</h2>
<p>Another benefit of placing a telescope far from the Sun is the lack of reflected light. The disc of dust in the plane of the planets reflects the Sun’s light back at Earth. This creates a haze that is between <a href="https://ned.ipac.caltech.edu/level5/March17/Cooray/Cooray1.html#1.4">100 and 1,000 times brighter than light from other galaxies</a> and obscures views of the cosmos from near Earth. Sending a telescope outside of this dust cloud would place it in a much darker region of space making it easier to measure the light coming from outside the solar system.</p>
<p>Once there, the telescope could measure the brightness of the ambient light of the universe over a wide range of wavelengths. This could provide insights into how <a href="https://ned.ipac.caltech.edu/level5/Madau2/Mad_contents.html">matter condensed into the first stars and galaxies</a>. It would also enable researchers to test models of the universe by comparing the predicted sum of light from all galaxies with a precise measurement. Discrepancies could point to problems with models of structure formation in the universe or perhaps to <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.150555">exotic new physics</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A blue horseshoe of light surrounding an orange galaxy." src="https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429166/original/file-20211028-5568-22i40f.jpeg?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"></a>
<figcaption>
<span class="caption">From far enough away, it would be possible to use the Sun as a giant lens, similar to the gravitational lensing seen here as light from a distant blue galaxy is bent around a nearer orange galaxy seen in the center.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Gravitational_lens#/media/File:A_Horseshoe_Einstein_Ring_from_Hubble.JPG">ESA/Hubble/NASA</a></span>
</figcaption>
</figure>
<h2>Into the unknown</h2>
<p>Finally, increasing a telescope’s distance from the Sun would also allow astronomers to do unique science that takes advantage of an <a href="https://hubblesite.org/contents/articles/gravitational-lensing">effect called gravitational lensing</a>, in which a massive object distorts the path light takes as it moves past an object.</p>
<p>One use of gravitational lensing is to <a href="https://theconversation.com/rogue-planets-hunting-the-galaxys-most-mysterious-worlds-149588">search for and weigh rogue planets</a> – planets that roam interstellar space after being ejected from their home solar systems. Since rogue planets don’t emit light on their own, astrophysicists can look for their <a href="https://www.universetoday.com/138141/gravitational-microlensing-method/">effect on the light from background stars</a>. To differentiate between the distance of the lensing object and its mass requires observations from a second location far from Earth.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An image showing how a planet will bend the light from a distant star." src="https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429162/original/file-20211028-13882-66luob.gif?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">Gravitational lensing caused by a planet passing in front of a distant star will bend light from that star, and that can also be used to detect dark planets that have been ejected from solar systems.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Gravitational_lens.gif#/media/File:Gravitational_lens.gif">NASA Ames/JPL-Caltech/T. Pyle via WikimediaCommons</a></span>
</figcaption>
</figure>
<p>In 2011, scientists used a camera on the EPOXI mission to the asteroid belt to discover and weigh a <a href="https://doi.org/10.1088/0004-637X/741/1/22">Neptune-sized object floating free among stars in the Milky Way galaxy</a>. Only a few rogue planets have been found, but astronomers suspect they are very common and could hold clues to the <a href="https://www.abc.net.au/news/2021-07-07/free-floating-planets-nasa-kepler-space-telescope/100273040">formation of solar systems and prevalence of planets around stars</a>.</p>
<p>But perhaps the most interesting use for a telescope in the outer solar system would be the potential to use the <a href="https://www.planetary.org/space-images/solar-gravity-lens-telescope">gravitational field of the Sun itself as a giant lens</a>. This kind of measurement may allow astrophysicists to actually map planets in other star systems. Perhaps one day we will be able to name continents on an Earth-like planet around a distant star.</p>
<p>[<em>Get the best of The Conversation, every weekend.</em> <a href="https://theconversation.com/us/newsletters/weekly-highlights-61?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=weeklybest">Sign up for our weekly newsletter</a>.]</p>
<h2>Coming soon?</h2>
<p>Since Pioneer 10 became the first human-made object to cross Jupiter’s orbit in 1973, there have been only a handful of astrophysical studies done from beyond the orbit of Earth. Missions to the outer solar system are rare, but many teams of scientists are doing <a href="https://www.universetoday.com/138141/gravitational-microlensing-method/">studies to show how an extrasolar telescope project would work</a> and what could be learned from one. </p>
<p>Every 10 years or so, leaders in the astrophysics and astronomy fields gather to set goals for the following decade. That plan for the 2020s is scheduled to be released on Nov. 4, 2021. In it, I expect to see discussions about the next telescope that could revolutionize astronomy. Taking a telescope to the outer solar system, while ambitious, is well within the technological ability of NASA or other space agencies. I hope that one day soon a tiny telescope out on a lonely mission in dark reaches of the solar system will provide us incredible insights into the universe.</p><img src="https://counter.theconversation.com/content/169805/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Zemcov receives funding from the National Aeronautics and Space Administration and the National Science Foundation.</span></em></p>Such a mission could be developed soon, allowing astrophysicists to take selfies of the solar system and use the Sun’s gravity as a lens to peer deep into space.Michael Zemcov, Associate Professor of Physics, Rochester Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1667152021-09-17T12:10:43Z2021-09-17T12:10:43ZHow many satellites are orbiting Earth?<figure><img src="https://images.theconversation.com/files/421399/original/file-20210915-14293-1wjwc0n.jpg?ixlib=rb-1.1.0&rect=8%2C1%2C750%2C499&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Thousands of the satellites orbiting Earth are small – like this cubical satellite seen here being released from the International Space Station.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/nasamarshall/24783645598/in/photolist-DL3Eos-2g25mh1-wYYTTe-X7fcWU-USsm8j-cWHRnY-tjYH6M-J4A9e5-2ggsEWo-2k3awWv-2dC3kEA-QZJn5h-YW2NkG-zkcYxm-hxEFAE-hxGaqc-N4fitw-k4woYu-kfZ3vX-2ke6Fxp-2kXUfFa-9ZT3gD-2j8CjNG-2mf1prm-2jaNJDv-soW6Bf-27r4vpy-9Nz3As-2jRr1P9-2kHskod-2kHwtaX-rs6muf-9dMsRi-s7wkDA-s7vaDW-rshGun-yEZ8FJ-smNyRh-2j9QNJa-rs6mbj-2keqFBm-oPKN18-2gr3mkN-m2SWHp-s7D7v6-2kHvXuJ-2jE3zHs-2ioBQGW-kfZ3tn-k31c8m">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/421720/original/file-20210916-25-2hsnlo.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421720/original/file-20210916-25-2hsnlo.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=255&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421720/original/file-20210916-25-2hsnlo.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=255&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421720/original/file-20210916-25-2hsnlo.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=255&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421720/original/file-20210916-25-2hsnlo.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=321&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421720/original/file-20210916-25-2hsnlo.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=321&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421720/original/file-20210916-25-2hsnlo.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=321&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>It seems like every week, another rocket is launched into space carrying <a href="https://theconversation.com/bringing-mars-rocks-back-to-earth-on-feb-18-perseverance-rover-landed-safely-on-mars-a-lead-scientist-explains-the-tech-and-goals-153851">rovers to Mars</a>, <a href="https://theconversation.com/spacex-inspiration4-mission-will-send-4-people-with-minimal-training-into-orbit-and-bring-space-tourism-closer-to-reality-167611">tourists</a> or, most commonly, <a href="https://theconversation.com/beanie-babies-the-invention-of-cubesat-and-student-designed-and-built-satellites-115354">satellites</a>. The idea that “<a href="https://www.msn.com/en-us/news/technology/space-is-becoming-too-crowded-rocket-lab-ceo-warns/ar-BB19NaOA">space is getting crowded</a>” has been around for a few years now, but just how crowded is it? And how crowded is it going to get?</p>
<p>I am a <a href="https://www.uml.edu/Profiles/supriya-chakrabarti.aspx">professor of physics</a> and director of the <a href="https://www.uml.edu/Research/LoCSST/">Center for Space Science and Technology</a> at the University of Massachusetts, Lowell. Many satellites that were put into orbit have gone dead and burned up in the atmosphere, but thousands remain. <a href="https://www.unoosa.org/oosa/osoindex/search-ng.jspx?lf_id=">Groups</a> that track <a href="https://brycetech.com/reports">satellite launches</a> don’t always report the same exact numbers, but the overall trend is clear – and astounding.</p>
<p>Since the Soviet Union launched Sputnik – the first human-made satellite – in 1957, humanity has steadily been putting more and more objects into orbit every year. Over the the second half of the 20th century, there was a slow but steady growth, with <a href="https://www.unoosa.org/oosa/osoindex/search-ng.jspx?lf_id=#?c=%7B%22filters%22:%5B%7B%22fieldName%22:%22en%23object.status.inOrbit_s1%22,%22value%22:%22Yes%22%7D%5D,%22sortings%22:%5B%7B%22fieldName%22:%22en%23object.status.objectStatus_s1%22,%22dir%22:%22asc%22%7D,%7B%22fieldName%22:%22object.status.dateOfDecay_s1%22,%22dir%22:%22desc%22%7D%5D,%22match%22:null%7D">roughly 60 to 100 satellites launched yearly until the early 2010s</a>.</p>
<p>But since then, the pace has been increasing dramatically.</p>
<p>By 2020, 114 launches carried around 1,300 satellites to space, surpassing the 1,000 new satellites per year mark for the first time. But no year in the past compares to 2021. As of Sept. 16, roughly 1,400 new satellites have already begun circling the Earth, and that will only increase as the year goes on. Just this week, SpaceX <a href="https://www.msn.com/en-us/news/technology/spacex-launchjes-51-starlinks-into-polar-orbit/ar-AAOpIcI">deployed another 51 Starlink satellites</a> into orbit. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Three people in white lab coats and hairnets working on a satellite roughly the size of a loaf of bread." src="https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421405/original/file-20210915-14-pryq7z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The ever-shrinking size of technology has led to tiny satellites like the one students are working on here.</span>
<span class="attribution"><span class="source">Edwin Aguirre/University of Massachusetts Lowell</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Small satellites, easy access to orbit</h2>
<p>There are two main reasons for this exponential growth. First, it has never been easier to get a satellite into space. For example, on Aug. 29, 2021, a <a href="https://en.wikipedia.org/wiki/SpaceX_CRS-23">SpaceX rocket</a> carried several satellites – including one <a href="https://www.uml.edu/Research/LoCSST/Research/spacehauc/news.aspx">built by my students</a> – to the International Space Station. On Oct. 11, 2021, these satellites will deploy into orbit, and the number of satellites will increase again.</p>
<p>The second reason is that rockets can carry more satellites more easily – and cheaply – than ever before. This increase isn’t due to rockets getting more powerful. Rather, satellites have gotten smaller thanks to the electronics revolution. The vast majority – 94% – of all spacecraft launched in 2020 were smallsats – <a href="https://brycetech.com/reports">satellites that weigh less than around 1,320 pounds (600 kilograms)</a>. </p>
<p>The majority of these satellites are used for observing Earth or for communications and internet. With a goal of bringing the internet to underserved areas of the globe, two private companies, <a href="https://www.starlink.com">Starlink by SpaceX</a> and <a href="https://onewebsatellites.com/about-us/">OneWeb</a> together launched almost 1,000 smallsats in 2020 alone. They are each <a href="https://www.osa-opn.org/home/articles/volume_32/may_2021/features/will_satellites_cripple_ground-based_astronomy/">planning to launch more than 40,000 satellites</a> in the coming years to create what are called “mega-constellations” in low-Earth orbit.</p>
<p>Several other companies are <a href="https://www.space.com/spacex-starlink-satellites.html">eyeing this US$1 trillion market</a>, most notably <a href="https://spectrum.ieee.org/amazons-project-kuiper-is-more-than-the-companys-response-to-spacex">Amazon with its Project Kuiper </a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/5h2t9Oyg2o0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Large satellite constellations – like SpaceX’s Starlink, seen in the video above – are set to dramatically increase the number of objects orbiting Earth and are already causing problems.</span></figcaption>
</figure>
<h2>A crowded sky</h2>
<p>With the huge growth in satellites, fears of a crowded sky are starting to come true. A day after SpaceX launched its first 60 Starlink satellites, astronomers began to <a href="https://www.youtube.com/watch?v=ytUygPqjXEc">see them blocking out the stars</a>. While the impact on visible astronomy is easy to understand, radio astronomers fear they may <a href="https://www.science.org/news/2020/10/starlink-already-threatens-optical-astronomy-now-radio-astronomers-are-worried">lose 70% sensitivity in certain frequencies due to interference from satellite megaconstellations</a> like Starlink.</p>
<p>Experts have been studying and discussing the <a href="https://aas.org/satellite-constellations-1-workshop">potential problems posed by these constellations</a> and ways the <a href="https://aas.org/satellite-constellations-2-workshop">satellite companies could address them </a>. These include reducing the number and brightness of satellites, sharing their location and supporting better image-processing software.</p>
<p>As low-Earth orbit gets crowded, <a href="https://www.esa.int/Safety_Security/Space_Debris/ESA_s_Space_Environment_Report_2021">concern about space debris</a> increases, as does a <a href="https://www.nature.com/articles/d41586-019-03446-y">real possibility</a> of <a href="https://swfound.org/media/6575/swf_iridium_cosmos_collision_fact_sheet_updated_2012.pdf">collisions</a>.</p>
<h2>Future trends</h2>
<p>Less than 10 years ago, the <a href="https://www.foreignaffairs.com/articles/space/2015-04-20/democratization-space">democratization of space was a goal yet to be realized</a>. Now, with <a href="https://www.wcvb.com/article/umass-designed-satellite-launched-up-to-international-space-station/37477067">student projects on the Space Station</a> and more than <a href="https://space.skyrocket.de/directories/sat_c.htm">105 countries</a> having at least one satellite in space, one could argue that that goal is within reach. </p>
<p>Every disruptive technological advancement requires updates to the rules – or the creation of new ones. SpaceX has tested ways to <a href="https://www.osa-opn.org/home/articles/volume_32/may_2021/features/will_satellites_cripple_ground-based_astronomy/">lower the impact of Starlink constellations</a>, and Amazon has disclosed plans to <a href="https://www.space.com/amazon-kuiper-satellite-constellation-fcc-approval.html">de-orbit their satellites within 355 days after mission completion</a>. These and other actions by different stakeholders make me hopeful that commerce, science and human endeavors will find sustainable solutions to this potential crisis.</p>
<p>[<em>The Conversation’s science, health and technology editors pick their favorite stories.</em> <a href="https://theconversation.com/us/newsletters/science-editors-picks-71/?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=science-favorite">Weekly on Wednesdays</a>.]</p><img src="https://counter.theconversation.com/content/166715/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Supriya Chakrabarti receives funding from NASA. He is affiliated with American Astronomical Society. </span></em></p>In the past decade, the number of satellites in orbit has skyrocketed thanks to tiny electronics and cheap launches. The crowded night sky is posing problems for astronomers and astronauts.Supriya Chakrabarti, Professor of Physics, UMass LowellLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1676112021-09-10T12:26:08Z2021-09-10T12:26:08ZSpaceX Inspiration4 mission sent 4 people with minimal training into orbit – and brought space tourism closer to reality<figure><img src="https://images.theconversation.com/files/420346/original/file-20210909-17-15tww6u.jpg?ixlib=rb-1.1.0&rect=0%2C210%2C4058%2C2612&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Four people – none of them trained astronauts – launched into orbit aboard a SpaceX Dragon capsule on Sept. 15, 2021.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/nasa2explore/8530582531/in/photolist-dZVaGL-dZVaEJ-dZPsZa-2j34sP1-2k5dwqg-2ih9wyp-2k5dwrd-2jsKxeR-2k7E9ZN-WHwz7z-2k5VEYS-2kVWxe5-2kVWsvN-2k7yNbd-2k7DYVJ-2k7vqNA-2dGyCqB-2j8rivC-2k7YwjW-2k7zrHo-2dGyCpe-2f1MeNC-2f1MeNY-2j6kLfz-2k7YAXy-2k7UeMw-2k7ySXh-2k7yXom-2k7urC3-6EK8CM-2kc9oZc-2dGyCsa-2jsJfFm-2k7Echy-2k7DQWD-2k7uKC6-2k7uNCz-2j8sAnT-b86SYZ-2kVSpM1-2f1MePj-2k7uGoL-2k7zwgX-2k7uDjQ-2k7zeLr-2jsJfQj-2gTsp44-2j6jfPB-2k7EdsE-2k7uUGJ/">NASA Johnson/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>Just after 8 p.m. EST on Sept. 15, 2021, the next batch of space tourists lifted off aboard a SpaceX rocket. Organized and funded by entrepreneur <a href="https://www.forbes.com/profile/jared-isaacman/?sh=c09ad2548698">Jared Isaacman</a>, the <a href="https://inspiration4.com/">Inspiration4 mission</a> touts itself as “the first all-civilian mission to orbit” and represents a new type of space tourism.</p>
<p>The four crew members are not the first space tourists this year. In the past few months, the world witnessed billionaires Richard Branson and Jeff Bezos launching themselves and a lucky few others into space on brief <a href="https://theconversation.com/whats-a-suborbital-flight-an-aerospace-engineer-explains-164279">suborbital trips</a>.</p>
<p>While there are similarities between those launches and Inspiration4 – the mission is being paid for by one billionaire and is using a rocket built by another, Elon Musk – the differences are noteworthy. From my perspective as a <a href="https://scholar.google.com/citations?user=PxIOz7cAAAAJ&hl=en&oi=ao">space policy expert</a>, the mission’s <a href="https://www.inverse.com/innovation/inspiration4-spacex-netflix">emphasis on public involvement</a> and the fact that Inspiration4 put regular people into orbit where they will stay for three days make it a milestone in space tourism.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four people standing in front of a rocket." src="https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420348/original/file-20210909-13-1n1m13x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The four crew members of the Inspiration4 mission are a physician assistant, a data engineer, a geoscientist and billionaire Jared Isaacman, left.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/inspiration4photos/51258513164/">Inspiration4/John Kraus via Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>Why Inspiration4 is different</h2>
<p>The biggest difference between Inspiration4 and the flights performed earlier this year is the destination. </p>
<p>Blue Origin and Virgin Galactic took – and in the future, will take – their passengers on <a href="https://theconversation.com/whats-a-suborbital-flight-an-aerospace-engineer-explains-164279">suborbital launches</a>. Their vehicles go only high enough to reach the beginning of space before returning to the ground a few minutes later. SpaceX’s Falcon 9 rocket and crew Dragon vehicle, however, are much more powerful and have taken the Inspiration4 crew all the way into orbit, where they will circle the Earth for three days.</p>
<p>The four-person crew is also quite different from those on the other launches. Led by Isaacman, the mission features a somewhat diverse group of people. One crew member, <a href="https://www.azcentral.com/story/news/local/arizona-science/2021/03/30/arizona-educator-sian-proctor-set-join-1st-spacex-private-flight/4804984001/">Sian Proctor</a>, won a contest among people who use Isaacman’s online payment company. Another unique aspect of the mission is that one of its goals is to raise awareness of and funds for St. Jude Children’s Research Hospital. As such, Isaacman selected <a href="https://www.nytimes.com/2021/02/22/science/spacex-hayley-arceneaux.html">Hayley Arceneaux</a>, a physician assistant at St. Jude and childhood cancer survivor, to participate in the launch. The final member, <a href="https://www.geekwire.com/2021/everett-engineer-arizona-prof-join-billionaires-crew-charity-space-trip/">Christopher Sembroski</a>, won his seat when his friend was chosen in a charity raffle for St. Jude and offered his seat to Sembroski.</p>
<p>Because none of the four participants had any prior formal astronaut training, the flight has been called the first all-civilian space mission. While the rocket and crew capsule are both fully automated – no one on board needed to control any part of the launch or landing – the four members still needed to go through much more training than the people on the suborbital flights. In less than six months, <a href="https://www.axios.com/spacex-astronaut-training-inspiration4-b3378a9a-88f9-4fb3-94a4-0e402453488c.html">crew members have undergone</a> hours of simulator training and lessons in flying a jet aircraft and spent time in a centrifuge to prepare them for the G-forces of launch.</p>
<p>Social outreach has also been an important aspect of the mission. While Bezos’ and Branson’s flights brought on <a href="https://theconversation.com/billionaire-space-race-the-ultimate-symbol-of-capitalisms-flawed-obsession-with-growth-164511">criticism of billionaire playboys in space</a>, Inspiration4 has tried – <a href="https://www.technologyreview.com/2021/09/08/1035219/netflix-spacex-docuseries-inspiration4-countdown/">with mixed results</a> – to make space tourism more relatable. The crew recently appeared on the <a href="https://time.com/6083977/jared-isaacman-inspiration4-profile/">cover of Time magazine</a> and is the subject of an ongoing <a href="https://www.netflix.com/title/81441273">Netflix documentary</a>.</p>
<p>There have also been other fundraising events for St. Jude, including a <a href="https://inspiration4miler.com/">4-mile virtual run</a> and the planned <a href="https://www.space.com/inspiration4-space-beer-hops-auction">auction of beer hops</a> that will be flown on the mission. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Colorful green and pink hues in the atmosphere of Earth with the blackness of space in the background." src="https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/420350/original/file-20210909-13-v16k6u.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 Inspiration4 mission is a step toward giving more people access to views like this – the aurora borealis seen from the International Space Station.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/image-feature/aurora-australis-lights-up-the-sky">NASA</a></span>
</figcaption>
</figure>
<h2>The future of space tourism?</h2>
<p>Sending a crew of amateur astronauts into orbit is a significant step in the development of space tourism. However, despite the more inclusive feel of the mission, there are still serious barriers to overcome before average people can go to space.</p>
<p>For one, the cost remains quite high. Though three of the four are not rich, Isaacman is a billionaire and <a href="https://time.com/6083977/jared-isaacman-inspiration4-profile/">paid an estimated $200 million</a> to fund the trip. The need to train for a mission like this also means that prospective passengers must be able to devote significant amounts of time to prepare – time that many ordinary people don’t have.</p>
<p>Finally, <a href="https://www.nasa.gov/hrp/5-hazards-of-human-spaceflight">space remains a dangerous place</a>, and there will never be a way to fully remove the danger of launching people – whether untrained civilians or seasoned professional astronauts – into space.</p>
<p>[<em>Over 110,000 readers rely on The Conversation’s newsletter to understand the world.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=100Ksignup">Sign up today</a>.]</p>
<p>Despite these limitations, orbital space tourism is coming. For SpaceX, Inspiration4 is an important proof of concept that demonstrated the safety and reliability of their autonomous rocket and capsule systems. Indeed, SpaceX has <a href="https://www.cnet.com/news/spacex-signs-blockbuster-deal-to-send-space-tourists-to-the-iss/">several tourist missions planned in the next few months</a>, even though the company isn’t focused on space tourism. Some will even includes stops at the International Space Station.</p>
<p>Even as space remains out of reach for most on Earth, Inspiration4 is an example of how billionaire space barons’ efforts to include more people on their journeys can give an otherwise exclusive activity a wider public appeal.</p>
<p><em>This is an updated version of an article originally published on Sept. 10, 2021.</em></p><img src="https://counter.theconversation.com/content/167611/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>The Inspiration4 mission sent four civilians to space for three days. Though still funded by a billionaire, the mission is a step forward in the nascent space tourism industry.Wendy Whitman Cobb, Professor of Strategy and Security Studies, Air UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1646012021-07-19T13:45:14Z2021-07-19T13:45:14ZSpace tourism: rockets emit 100 times more CO₂ per passenger than flights – imagine a whole industry<p>The commercial race to get tourists to space is heating up between Virgin Group founder Sir Richard Branson and former Amazon CEO Jeff Bezos. On Sunday 11 July, Branson ascended 80 km to reach the edge of space in his piloted <a href="https://www.bbc.co.uk/news/science-environment-57797297">Virgin Galactic VSS Unity</a> spaceplane. Bezos’ autonomous Blue Origin rocket <a href="https://www.cnbc.com/2021/06/07/jeff-bezos-to-fly-on-blue-origin-first-passenger-flight-in-july.html">is due to launch on July 20</a>, coinciding with the anniversary of the Apollo 11 Moon landing. </p>
<p>Though Bezos loses to Branson in time, he is set to reach higher altitudes (<a href="https://www.ft.com/content/621ddc59-11fe-4101-8abf-701a53b2475f">about 120 km</a>). The launch will demonstrate his offering to very wealthy tourists: the opportunity to truly reach outer space. Both tour packages will provide passengers with a brief ten-minute frolic in zero gravity and glimpses of Earth from space. Not to be outdone, Elon Musk’s SpaceX will provide four to five days of <a href="https://www.space.com/spacex-crew-dragon-will-fly-space-tourists.html">orbital travel</a> with its Crew Dragon capsule later in 2021.</p>
<p>What are the environmental consequences of a space tourism industry likely to be? Bezos boasts his Blue Origin rockets are <a href="https://twitter.com/blueorigin/status/1413521631717122059?s=20">greener</a> than Branson’s VSS Unity. The Blue Engine 3 (BE-3) will <a href="https://www.space.com/blue-origin-jeff-bezos-new-shepard-first-crewed-launch-explained">launch</a> Bezos, his brother and two guests into space using liquid hydrogen and liquid oxygen propellants. VSS Unity used <a href="https://www.bbc.co.uk/news/science-environment-57798167">a hybrid propellant</a> comprised of a solid carbon-based fuel, hydroxyl-terminated polybutadiene (HTPB), and a liquid oxidant, nitrous oxide (laughing gas). The SpaceX Falcon series of reusable rockets will propel the Crew Dragon into orbit using liquid kerosene and liquid oxygen. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1416842252249444358"}"></div></p>
<p>Burning these propellants provides the energy needed to launch rockets into space while also generating greenhouse gases and air pollutants. Large quantities of water vapour are produced by burning the BE-3 propellant, while combustion of both the VSS Unity and Falcon fuels produces CO₂, soot and some water vapour. The nitrogen-based oxidant used by VSS Unity also generates nitrogen oxides, compounds that contribute to air pollution closer to Earth.</p>
<p>Roughly <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016EF000399">two-thirds</a> of the propellant exhaust is released into the stratosphere (12 km-50 km) and mesosphere (50 km-85 km), where it can persist for at least two to three years. The very high temperatures during launch and re-entry (when the protective heat shields of the returning crafts burn up) also convert stable nitrogen in the air into reactive nitrogen oxides.</p>
<p>These gases and particles have many negative effects on the atmosphere. In the stratosphere, nitrogen oxides and chemicals formed from the breakdown of water vapour convert ozone into oxygen, depleting the ozone layer which guards life on Earth against harmful UV radiation. Water vapour also produces stratospheric clouds that provide a surface for this reaction to occur at a faster pace than it otherwise would. </p>
<h2>Space tourism and climate change</h2>
<p>Exhaust emissions of CO₂ and soot trap heat in the atmosphere, contributing to global warming. Cooling of the atmosphere can also occur, as clouds formed from the emitted water vapour reflect incoming sunlight back to space. A depleted ozone layer would also absorb less incoming sunlight, and so heat the stratosphere less. </p>
<p>Figuring out the overall effect of rocket launches on the atmosphere will require detailed modelling, in order to account for these complex processes and the persistence of these pollutants in the upper atmosphere. Equally important is a clear understanding of how the space tourism industry will develop. </p>
<p>Virgin Galactic anticipates it will offer <a href="https://www.ft.com/content/0d9c9174-9374-4c48-a25b-3ae7dd6764b3">400 spaceflights each year</a> to the privileged few who can afford them. Blue Origin and SpaceX have yet to announce their plans. But globally, rocket launches wouldn’t need to increase by much from the current <a href="https://www.spacelaunchreport.com/logyear.html">100 or so performed each year</a> to induce harmful effects that are <a href="https://everydayastronaut.com/rocket-pollution/">competitive with other sources</a>, like ozone-depleting chlorofluorocarbons (CFCs), and CO₂ from aircraft. </p>
<p>During launch, rockets can emit between four and ten times more nitrogen oxides than <a href="https://naei.beis.gov.uk/data/map-large-source">Drax</a>, the largest thermal power plant in the UK, over the same period. CO₂ emissions for the four or so tourists on a space flight will be between 50 and 100 times more than the <a href="https://www.theguardian.com/environment/ng-interactive/2019/jul/19/carbon-calculator-how-taking-one-flight-emits-as-much-as-many-people-do-in-a-year">one to three tonnes</a> per passenger on a long-haul flight.</p>
<p>In order for international regulators to keep up with this nascent industry and control its pollution properly, scientists need a better understanding of the effect these billionaire astronauts will have on our planet’s atmosphere.</p><img src="https://counter.theconversation.com/content/164601/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eloise Marais receives funding from UKRI, the European Commission and DEFRA. </span></em></p>Here’s what a space tourism industry led by Bezos, Branson and Musk might mean for the planet.Eloise Marais, Associate Professor in Physical Geography, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1608532021-05-17T16:58:48Z2021-05-17T16:58:48ZGaza’s enhanced rocket technology challenges Israel’s defences<figure><img src="https://images.theconversation.com/files/400886/original/file-20210516-19-y98z8l.jpg?ixlib=rb-1.1.0&rect=52%2C824%2C5858%2C3043&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Israeli Iron Dome air defense system launches to intercept rockets fired from Gaza Strip, near Sderot, Israel.</span> <span class="attribution"><span class="source">(AP Photo/Ariel Schalit)</span></span></figcaption></figure><p>Gaza militants have launched their <a href="https://www.nytimes.com/2021/05/11/world/middleeast/israel-gaza-airstrikes.html">“Sword of Jerusalem” rocket war</a> with Israel by firing a symbolic salvo at Jerusalem and bigger ones elsewhere. Israel’s <a href="https://mfa.gov.il/MFA/ForeignPolicy/Terrorism/Palestinian/Pages/Operation-Guardian-of-the-Walls-10-May-2021.aspx">“Guardian of the Walls” operation</a> responded with Iron Dome interceptors at home and airstrikes in Gaza.</p>
<p>As someone who’s researched Israeli missile defence systems for several years, the situation initially seemed to me like a repeat of <a href="https://www.bbc.com/news/world-middle-east-33223365">their 2014 conflict</a>, which showcased Israel’s advanced defences. But militants in Gaza have enhanced their rocket technology and tactics. <a href="https://www.middleeastmonitor.com/20181227-remembering-israels-2008-war-on-gaza/">That’s reminiscent of 2008</a>, when Israel was more vulnerable to rockets and waged a three-week military offensive against Gaza.</p>
<figure class="align-center ">
<img alt="A ruined building" src="https://images.theconversation.com/files/401051/original/file-20210517-13-1u7m0tv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/401051/original/file-20210517-13-1u7m0tv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=410&fit=crop&dpr=1 600w, https://images.theconversation.com/files/401051/original/file-20210517-13-1u7m0tv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=410&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/401051/original/file-20210517-13-1u7m0tv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=410&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/401051/original/file-20210517-13-1u7m0tv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=515&fit=crop&dpr=1 754w, https://images.theconversation.com/files/401051/original/file-20210517-13-1u7m0tv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=515&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/401051/original/file-20210517-13-1u7m0tv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=515&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Palestinians inspect damaged houses that were hit in early morning Israeli airstrikes in Gaza City.</span>
<span class="attribution"><span class="source">(AP Photo/Khalil Hamra)</span></span>
</figcaption>
</figure>
<p>According to the Israel Defense Forces, <a href="https://twitter.com/IDF/status/1393992449979260928">roughly 3,100 rockets</a> have been fired from Gaza. That’s about as many as during the seven-week battle in 2014. (All rocket numbers in this article were reported by the Israel Defense Forces or Israel Security Agency. There is no way to independently verify most of them.) </p>
<p>Israeli news reports say they’ve caused <a href="https://www.jpost.com/arab-israeli-conflict/homes-in-southern-israel-sustain-direct-hits-as-rockets-rain-down-668232">10 civilian deaths and more than 564 injuries</a>, while <a href="https://www.aljazeera.com/news/2021/5/16/more-deaths-gaza-israel-launches-most-intense-raids-yet">Israeli countermeasures have killed almost 200 Palestinians</a> and <a href="https://www.cnn.com/2021/05/16/middleeast/israel-palestinian-conflict-intl/index.html">resulted in scenes of carnage and devastation.</a></p>
<figure class="align-center ">
<img alt="Bar chart showing number of rockets fired per year from 2005 to 16 May 2021." src="https://images.theconversation.com/files/400900/original/file-20210516-23-w97sfx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400900/original/file-20210516-23-w97sfx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=407&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400900/original/file-20210516-23-w97sfx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=407&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400900/original/file-20210516-23-w97sfx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=407&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400900/original/file-20210516-23-w97sfx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=511&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400900/original/file-20210516-23-w97sfx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=511&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400900/original/file-20210516-23-w97sfx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=511&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Rockets fired per year from Gaza toward Israel, from 2005 to 16 May 2021, according to Israel Defence Forces/Israel Security Agency.</span>
<span class="attribution"><span class="source">Created by Michael Armstrong from published Israeli data.</span></span>
</figcaption>
</figure>
<p>The counts have risen so quickly because Gaza militants have <a href="https://www.jpost.com/arab-israeli-conflict/iran-reveals-its-strategy-advising-hamas-on-war-against-israel-668265">improved their rockets and their usage of them</a>.</p>
<h2>Improved rocketry</h2>
<p>The most noticeable change this year is larger quantities. Gaza militants fired 470 rockets during the first 24 hours and have averaged 408 per day. Those numbers easily beat the one-day maximums of 316 in 2012 and 192 in 2014.</p>
<p>The firing is also better co-ordinated. Rather than launching many small attacks spread across the day, they’ve unleashed larger salvos of up to <a href="https://www.timesofisrael.com/2-killed-by-rockets-in-ashkelon-amid-massive-barrages-from-gaza/">137 rockets within five minutes</a>. That’s much improved, though still far slower than <a href="https://www.youtube.com/watch?v=0-SN9Cxao5M">regular army</a> <a href="https://www.youtube.com/watch?v=0vZKXGRpf5c">artillery units</a>.</p>
<p>Accuracy has improved, too. About 50 per cent of the rockets arriving over Israel have threatened populated areas. That’s up from 22 per cent in 2012 and 18 per cent in 2014. Fewer rockets land in empty fields after missing their targets.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1393069600137531392"}"></div></p>
<p>Larger, longer-range rockets are also more common now. During previous conflicts, Israel’s southern cities endured most of the fire. This time, <a href="https://goo.gl/maps/HHA716t1JF3Qmuxw7">Tel Aviv</a>, in central Israel more than 55 kilometres from Gaza’s border, is routinely targeted.</p>
<p>Rocket reliability, however, has dropped. About 15 per cent have failed at launch, versus under 10 per cent during previous conflicts.</p>
<h2>Destructive impact</h2>
<p>The improved technology and tactics make barrages more destructive. My calculations suggest at least 134 rockets have hit populated areas.</p>
<p>During the first four days of this conflict, one Israeli died for every 206 rockets reaching the country. That approaches the one-per-204 rate of 2008, when Israel’s defences were weaker. By comparison, it took 270 rockets to kill a civilian in 2012 and 1,429 in 2014. </p>
<p>The injury rate, about one for every three rockets arriving overhead, also resembles 2008. And many buildings have been damaged.</p>
<figure class="align-center ">
<img alt="Rocket destruction, including decimated palm trees and cars covered in rubble and debris." src="https://images.theconversation.com/files/400895/original/file-20210516-17-owsize.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400895/original/file-20210516-17-owsize.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400895/original/file-20210516-17-owsize.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400895/original/file-20210516-17-owsize.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400895/original/file-20210516-17-owsize.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400895/original/file-20210516-17-owsize.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400895/original/file-20210516-17-owsize.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">Israeli firefighters works at the site where a rocket fired from the Gaza Strip hit the central Israeli town of Holon, near Tel Aviv.</span>
<span class="attribution"><span class="source">(AP Photo/Heidi Levine)</span></span>
</figcaption>
</figure>
<p>These results imply that shock-and-awe destruction is the 2021 strategy of Gaza militants. By comparison, the 2014 operation mostly featured economic attrition. Israel suffered relatively few civilian casualties <a href="https://www.ft.com/content/af80d236-74c6-11e4-a418-00144feabdc0">but heavy financial costs</a> from the prolonged disruption.</p>
<p>Both then and now, Israel has responded with <a href="https://theconversation.com/north-korea-missile-crisis-echoes-israels-anti-rocket-strategy-82415">several countermeasures</a>.</p>
<h2>Blocking (many) rockets</h2>
<p><a href="https://theconversation.com/as-missiles-fly-a-look-at-israels-iron-dome-interceptor-94959">Iron Dome interceptors</a> provide the best-known defence. Israel claims the systems <a href="https://twitter.com/sfrantzman/status/1393995143582298113">intercepted 1,210 rockets</a> last week, or 90 per cent of the rockets they engaged. That’s about the percentage they achieved in 2014, too, <a href="https://doi.org/10.1093/jogss/ogx028">though perhaps not in 2012</a>.</p>
<figure class="align-center ">
<img alt="An Iron Dome air defence system fires to intercept a rocket" src="https://images.theconversation.com/files/400897/original/file-20210516-23-1q55dfd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400897/original/file-20210516-23-1q55dfd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400897/original/file-20210516-23-1q55dfd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400897/original/file-20210516-23-1q55dfd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400897/original/file-20210516-23-1q55dfd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400897/original/file-20210516-23-1q55dfd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400897/original/file-20210516-23-1q55dfd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">In this July 2014 photo, an Iron Dome air defence system fires to intercept a rocket from Gaza Strip in the costal city of Ashkelon, Israel.</span>
<span class="attribution"><span class="source">(AP Photo/Tsafrir Abayov)</span></span>
</figcaption>
</figure>
<p>Are they always achieving it now? </p>
<p>With bigger barrages and greater accuracy, more rockets are arriving together above each target. That means there’s more risk the interceptors will become overloaded and let some rockets through.</p>
<p>Suppose the systems sometimes block “only” 80 per cent of rockets. That’s still impressive. But it means the portion penetrating then doubles from 10 to 20 per cent, causing twice the destruction.</p>
<p><a href="https://doi.org/10.1287/opre.2014.1309">My research seven years ago</a> analyzed this tactic. It showed that high-performing interceptors can seem “fragile” — once their capacity is exceeded, damage on the ground soars.</p>
<p>That research also studied the idea of firing directly at interceptor systems to disable them. Sure enough, one barrage <a href="https://www.jpost.com/middle-east/iran-says-hamas-is-targeting-iron-dome-sites-airports-668194">recently made such an attempt</a>. That was likely a waste of ammo, as their rockets aren’t accurate enough yet for such small targets.</p>
<p>Ironically, one Iron Dome system was briefly disabled two days earlier by an equipment malfunction. <a href="https://www.timesofisrael.com/1-killed-3-injured-as-hamas-fires-anti-tank-missile-at-israeli-jeep/">That let some extra rockets through</a>.</p>
<p>Israel also has <a href="https://www.idf.il/en/minisites/home-front-command/">extensive warning systems and bomb shelters</a>. Those prevent as many casualties as interceptors do, but don’t stop property damage.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/israeli-rocket-experience-shows-bomb-shelters-matter-as-much-as-interceptors-96402">Israeli rocket experience shows bomb shelters matter as much as interceptors</a>
</strong>
</em>
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<p>Airstrikes are another Israeli countermeasure. Its aircraft began bombing <a href="https://www.timesofisrael.com/rocket-volleys-target-south-at-dawn-as-idf-hits-key-hamas-positions/">rocket stockpiles and launchers</a> last week, followed by production sites and other targets.</p>
<p>But while its bombers can destroy rocket stockpiles and workshops, they don’t have much immediate effect on firing rates. <a href="https://doi.org/10.1093/jogss/ogx028">My analysis of previous operations</a> found that airstrikes didn’t decrease daily fire rates; only ground assaults did that</p>
<p>Collateral damage is another problem. Bombs have damaged <a href="https://apnews.com/article/israel-west-bank-gaza-middle-east-israel-palestinian-conflict-7974cc0c03897b8b21e5fc2f8c7d8a79">or completely destroyed</a> many buildings. And almost <a href="https://www.aljazeera.com/news/2021/5/16/more-deaths-gaza-israel-launches-most-intense-raids-yet">200 Palestinian militants and civilians</a> have died so far.</p>
<figure class="align-center ">
<img alt="A woman cries standing near the rubble of a building." src="https://images.theconversation.com/files/400893/original/file-20210516-17-7wwkj4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400893/original/file-20210516-17-7wwkj4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400893/original/file-20210516-17-7wwkj4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400893/original/file-20210516-17-7wwkj4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400893/original/file-20210516-17-7wwkj4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=528&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400893/original/file-20210516-17-7wwkj4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=528&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400893/original/file-20210516-17-7wwkj4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=528&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A woman reacts while standing near the rubble of a building that was destroyed by an Israeli airstrike on Saturday that housed The Associated Press, broadcaster Al-Jazeera and other media outlets in Gaza City.</span>
<span class="attribution"><span class="source">(AP Photo/Adel Hana)</span></span>
</figcaption>
</figure>
<h2>What next?</h2>
<p>Gaza’s <a href="https://www.jpost.com/arab-israeli-conflict/what-do-hamas-and-pij-have-in-their-rocket-arsenals-analysis-667856">14,000-rocket arsenal</a> could support short-range barrages <a href="https://www.jpost.com/middle-east/idf-military-intelligence-knew-hamas-would-fire-on-jerusalem-668192">for months</a>. </p>
<p>But it will likely run out of long-range rockets sooner, making a truce look more attractive. Israel might favour a truce soon, too, as it runs out of meaningful airstrike targets.</p>
<p>Let’s hope that truce happens soon. The alternatives are a prolonged war of aerial attrition, or a costly ground battle in Gaza.</p><img src="https://counter.theconversation.com/content/160853/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael J. Armstrong 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>Improved rocket technology and tactics have made the ongoing Gaza-Israel conflict different from the one in 2014. Israel’s defences have been stressed.Michael J. Armstrong, Associate professor of operations research, Goodman School of Business, Brock UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1607572021-05-17T12:25:43Z2021-05-17T12:25:43ZIf a satellite falls on your house, space law protects you – but there are no legal penalties for leaving junk in orbit<figure><img src="https://images.theconversation.com/files/400832/original/file-20210514-13-1mq0r5w.jpg?ixlib=rb-1.1.0&rect=0%2C17%2C6000%2C3664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">It's unlikely falling space junk will destroy property or kill a person. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/satellite-royalty-free-image/476204650?adppopup=true">Petrovich9/iStock via Getty Images</a></span></figcaption></figure><p>On May 8, 2021, a piece of space junk from a Chinese rocket fell uncontrolled back to Earth and <a href="https://www.nytimes.com/2021/05/08/science/china-rocket-reentry-falling-long-march-5b.html">landed in the Indian Ocean near the Maldives</a>. A year ago, in May 2020, another Chinese rocket met the same fate when it plummeted out of control into the waters <a href="https://www.theverge.com/2020/5/13/21256484/china-rocket-debris-africa-uncontrolled-reentry-long-march-5b">off the West African coast</a>. No one knew when or where either of these pieces of space junk were going to hit, so it was a relief when neither crashed on land or injured anyone.</p>
<p>Space debris is any nonfunctional human-made object in space.
As a professor of <a href="https://sfis.asu.edu/timiebi-aganaba-jeanty">space and society focused on space governance</a>, I’ve noticed that there are three questions the public always asks when falling space debris gets into the news. Could this have been prevented? What would have happened if there was damage? And how will new commercial companies be regulated as space activities and launches <a href="https://www.euroconsult-ec.com/research/WS319_free_extract_2019.pdf">increase exponentially</a>?</p>
<p>For space law to be effective, it <a href="https://unoosa.org/pdf/pres/stsc2011/tech-35.pdf">needs to do three things</a>. First, regulation must prevent as many dangerous situations from occurring as possible. Second, there needs to be a way to monitor and enforce compliance. And finally, laws need to lay out a framework for responsibility and liability if things do go wrong. So, how do current laws and treaties around space stack up? They do OK, but interestingly, looking at environmental law here on Earth may give some ideas on how to improve the current legal regime with respect to space debris.</p>
<h2>What if a rocket landed on your house?</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A large white rocket on a launch pad." src="https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1067&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1067&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1067&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1340&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1340&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400833/original/file-20210514-15-8pfz57.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1340&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Two Chinese Long March 5b rockets, like the one seen here, have crashed into the ocean within the past year.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:%E9%95%BF%E5%BE%81%E4%BA%94%E5%8F%B7%E9%81%A5%E4%BA%8C%E7%81%AB%E7%AE%AD%E8%BD%AC%E5%9C%BA.jpg#/media/File:%E9%95%BF%E5%BE%81%E4%BA%94%E5%8F%B7%E9%81%A5%E4%BA%8C%E7%81%AB%E7%AE%AD%E8%BD%AC%E5%9C%BA.jpg">篁竹水声/WikimediaCommons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Imagine that, instead of landing in the ocean, the recent Chinese rocket crashed into your house while you were at work. What would current law allow you to do?</p>
<p>According to the <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introouterspacetreaty.html">1967 Outer Space Treaty</a> and <a href="https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introliability-convention.html">1972 Liability Convention</a> – both adopted by the United Nations – this would be a government-to-government issue. The treaties declare that states are internationally responsible and liable for any damage caused by a spacecraft – even if the damage was caused by a private company from that state. According to these laws, your country wouldn’t even need to prove that someone had done something wrong if a space object or its component parts caused damage on the surface of the Earth or to normal aircraft in flight. </p>
<p>Basically, if a piece of space junk from China landed on your house, your own country’s government would make a claim for compensation through diplomatic channels and then pay you – if they chose to make the claim at all.</p>
<p>While the chances are slim to none that a broken satellite will land on your house, space debris has crashed onto land. In 1978, the Soviet Cosmos 954 satellite <a href="https://nationalinterest.org/feature/operation-morning-light-the-nuclear-satellite-almost-14411?page=1">fell into a barren region of Canada’s Northwest Territories</a>. When it crashed, it spread radioactive debris from its onboard nuclear reactor over a wide swath of land. A joint Canadian-American team began a cleanup effort that cost over CAD$14 million (US$11.5 million). The Canadians requested CAD$6 million from the Soviet Union, but the Soviets paid only CAD$3 million in the final settlement.</p>
<p>This was the first – and only – time the Liability Convention has been used when a spacecraft from one country has crashed in another. When the Liability Convention was put into use in this context, <a href="https://digitalcommons.law.yale.edu/cgi/viewcontent.cgi?article=1316&context=yjil">four governing norms emerged</a>. Countries have a duty to: warn other governments about debris; provide any information they could about an impending crash; clean up any damage caused by the craft; and compensate your government for any injuries that might have resulted.</p>
<p>There have been other instances where <a href="https://www.space.com/13049-6-biggest-spacecraft-falls-space.html">space junk has crashed back to Earth</a> – most notably when <a href="https://www.abc.net.au/news/2019-07-12/four-decades-on-from-skylabs-descent-from-space/11249626">Skylab, a U.S. space station, fell and broke up</a> over the Indian Ocean and uninhabited parts of Western Australia in 1979. A local government jokingly fined NASA AUS$400 (US$311) for littering – a fine that NASA ignored, though it was eventually <a href="https://www.skymania.com/wp/nasas-litter-bill-paid-30-years-on/">paid by an American radio host in 2009</a>. But despite this and other incidences, Canada remains the only country to put the Liability Convention to use.</p>
<p>However, if you owned a small orbiting satellite that got hit by a piece of space junk, you and your government would have to prove who was at fault. Currently, though, there is <a href="https://theconversation.com/a-giant-piece-of-space-junk-is-hurtling-towards-earth-heres-how-worried-you-should-be-160254?">no globally coordinated space traffic management system</a>. With tens of thousands of tracked pieces of debris in orbit – and multitudes of smaller, untrackable pieces, figuring out what destroyed your satellite would be a very difficult thing to do. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An image of the Earth surrounded by a cloud of yellow dots." src="https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400834/original/file-20210514-23-qydc5a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Every dot in this image represents a known piece of space debris.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Debris-GEO1280.jpg#/media/File:Debris-GEO1280.jpg">NASA Orbital Debris Program/WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>Space pollution is the bigger problem</h2>
<p>Current space law has worked so far because the issues have been few and far between and have been dealt with diplomatically. As more and more spacecraft take flight, the risks to property or life will inevitably increase and the Liability Convention may get more use.</p>
<p>But risks to life and property are not the only concerns about a busy sky. While launch providers, satellite operators and insurance companies care about the problem of space debris for its <a href="https://www.bvp.com/atlas/why-removing-space-debris-requires-caution-and-action">effect on space operations</a>, space sustainability advocates argue that the <a href="https://theconversation.com/final-frontiers-space-13171">environment of space has value itself</a> and faces a much greater risk of harm than individuals on Earth. </p>
<p>The mainstream view is that degrading the environment on Earth through pollution or mismanagement is bad because of its <a href="https://www.nationalgeographic.org/encyclopedia/pollution/">negative impact on the environment or living beings</a>. The same is true for space, even if there is no clear direct victim or physical harm. In the <a href="https://www.jaxa.jp/library/space_law/chapter_3/3-2-2-1_e.html">Cosmos 954 settlement</a>, the Canadians claimed that since the Soviet satellite deposited hazardous radioactive debris in Canadian territory, this constituted “damage to property” within the meaning of the Liability Convention. But, as Article 2 of the Outer Space Treaty declares that no state can own outer space or celestial bodies, it is not clear whether this interpretation would apply in the event of harm to objects in space. Space is shaping up to be a new frontier on which the tragedy of the commons can play out.</p>
<p><a href="https://www.nasa.gov/pdf/582393main_OCT-Orbital_Debris_TAGGED.pdf">Removing from orbit existing large objects</a> that could collide with one another would be a great place for governments to start. But if the United Nations or governments agreed on laws that define legal consequences for creating space debris in the first place and punishment for not following best practices, this could help mitigate future pollution of the space environment. </p>
<p>[<em>Understand new developments in science, health and technology, each week.</em> <a href="https://theconversation.com/us/newsletters/science-editors-picks-71/?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=science-understand">Subscribe to The Conversation’s science newsletter</a>.]</p>
<p>Such laws would not need to be invented from scratch. The <a href="https://www.unoosa.org/pdf/publications/st_space_49E.pdf">2007 United Nations Space Debris Mitigation guidelines</a> already address the issue of debris prevention. While some countries have transferred these guidelines into national regulations, worldwide implementation is still pending, and there are <a href="http://www.esa.int/Safety_Security/Space_Debris/Mitigating_space_debris_generation">no legal consequences for noncompliance</a>.</p>
<p>The chances of a person being killed by a falling satellite are close to zero. On the off chance it does happen, current space law provides a pretty good framework for dealing with such an event. But just like during the early 20th century on Earth, current laws are focusing on the individual and ignoring the bigger picture of the environment – albeit a cold, dark and unfamiliar one. Adapting and enforcing space law so that it prevents and deters actors from polluting the space environment – and holds them accountable if they break these laws – could help avoid a trash-filled sky.</p>
<p><em>This is an updated version of an article originally published on May 17, 2021. It has been updated to clarify the history of falling space debris.</em></p><img src="https://counter.theconversation.com/content/160757/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Timiebi Aganaba 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>Chances are small that space junk will destroy property or harm a person, and existing space law could deal with such an event. But current law doesn’t address the bigger problem of space pollution.Timiebi Aganaba, Assistant Professor of Space and Society, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1605102021-05-07T12:44:42Z2021-05-07T12:44:42ZSpace tourism is here – 20 years after the first stellar tourist, Jeff Bezos’ Blue Origin plans to send civilians to space<figure><img src="https://images.theconversation.com/files/399324/original/file-20210506-17-zm3v4c.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4114%2C2792&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Astronaut Tracy Caldwell Dyson on the International Space Station with a view many more are likely to see soon. </span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Tracy_Caldwell_Dyson_in_Cupola_ISS.jpg#/media/File:Tracy_Caldwell_Dyson_in_Cupola_ISS.jpg">NASA/Tracy Caldwell Dyson/WIkimediaCommons</a></span></figcaption></figure><p>For most people, getting to the stars is nothing more than a dream. But on May 5, 2021, the 60th anniversary of the first suborbital flight, that dream became a little bit more achievable. </p>
<p>The space company Blue Origin announced that it would <a href="https://www.nbcnews.com/science/space/jeff-bezos-blue-origin-auction-seat-space-tourism-flight-rcna828">start selling tickets for suborbital flights to the edge of space</a>. The first flight is scheduled for July 20, and Jeff Bezos’ company is <a href="https://www.nytimes.com/2021/05/05/science/blue-origin-space-jeff-bezos.html">auctioning off one single ticket to the highest bidder</a>. </p>
<p>But whoever places the winning bid won’t be the first tourist in space.</p>
<p>On April 28, 2001, Dennis Tito, a wealthy businessman, <a href="https://www.space.com/11492-space-tourism-pioneer-dennis-tito.html">paid US$20 million for a seat on a Russian Soyuz</a> spacecraft to be the first tourist to visit the International Space Station. Only <a href="https://spaceadventures.com/experiences/space-station/">seven civilians have followed suit</a> in the 20 years since, but that number is poised to double in the next 12 months alone.</p>
<p>NASA has long been <a href="http://www.spaceref.com/news/viewnews.html?id=304">hesitant to play host to space tourists</a>, so Russia – looking for sources of money post-Cold War in the 1990s and 2000s – has been the only option available to those looking for this kind of extreme adventure. However, it seems the rise of private space companies is going to make it easier for regular people to experience space.</p>
<p>From my perspective as <a href="https://scholar.google.com/citations?user=PxIOz7cAAAAJ&hl=en&oi=ao">a space policy analyst</a>, recent announcements from companies like Blue Origin and SpaceX are the opening of an era in which more people can experience space. Hoping to build a future for humanity in space, these companies are seeking to use space tourism as a way to demonstrate both the safety and reliability of space travel to the general public.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Three men floating in the International Space Station" src="https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.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"></a>
<figcaption>
<span class="caption">Dennis Tito, on the left beside two Russian astronauts, was the first private citizen to ever go to space – and he spent more than a week on the International Space Station.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:ISS-02_Soyuz_TM-32_Taxi_crewmembers.jpg#/media/File:ISS-02_Soyuz_TM-32_Taxi_crewmembers.jpg">NASA/WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>The development of space tourism</h2>
<p>Flights to space like Dennis Tito’s are expensive for a reason. A rocket must burn a lot of costly fuel to travel high and fast enough to enter Earth’s orbit.</p>
<p>Another cheaper possibility is a suborbital launch, with the rocket going high enough to reach the edge of space and coming right back down. This is the kind of flight that Blue Origin is now offering. While passengers on a suborbital trip experience weightlessness and incredible views, these launches are more accessible.</p>
<p>The difficulty and expense of either option has meant that, traditionally, only nation-states have been able to explore space. This began to change in the 1990s as a series of entrepreneurs entered the space arena. Three companies led by billionaire CEOs have emerged as the major players: Blue Origin, SpaceX and Virgin Galactic. Though none have taken paying, private customers to space, all anticipate doing so in the very near future.</p>
<p>British billionaire Richard Branson has built his brand on not just business but also his love of adventure. In pursuing space tourism, Branson has brought both of those to bear. He established <a href="https://www.virgingalactic.com/">Virgin Galactic</a> after buying <a href="https://www.space.com/16769-spaceshipone-first-private-spacecraft.html">SpaceShipOne</a> – a company that won the <a href="https://www.xprize.org/prizes/ansari">Ansari X-Prize</a> by building the first reusable spaceship. Since then, Virgin Galactic has sought to design, build and fly a larger <a href="https://www.virgingalactic.com/learn/">SpaceShipTwo</a> that can carry up to six passengers in a suborbital flight.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A silvery ship that looks like a fighter plane with elongated tail fins." src="https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=320&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=320&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=320&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=402&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=402&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=402&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 VSS Unity spacecraft is one of the ships that Virgin Galactic plans to use for space tours.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/VirginGalactic/c699fbc80ae44738a66a899dffd37b6a/photo?Query=virgin%20AND%20galactic&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=375&currentItemNo=13">AP Photo/Matt Hartman</a></span>
</figcaption>
</figure>
<p>The going has been harder than anticipated. While Branson <a href="http://news.bbc.co.uk/2/hi/science/nature/7529978.stm">predicted opening the business</a> to tourists in 2009, Virgin Galactic has encountered some significant hurdles – including the death of a pilot in <a href="https://www.space.com/30073-virgin-galactic-spaceshiptwo-crash-pilot-error.html">a crash in 2014</a>. After the crash, engineers found significant problems with the design of the vehicle, which required modifications.</p>
<p>Elon Musk and Jeff Bezos, respective leaders of SpaceX and Blue Origin, began their own ventures in the early 2000s.</p>
<p>Musk, <a href="https://www.space.com/spacex-starship-first-mars-trip-2024">fearing that a catastrophe</a> of some sort could leave Earth uninhabitable, was frustrated at the lack of progress in making humanity a multiplanetary species. He founded SpaceX in 2002 with the goal of first developing reusable launch technology to decrease the cost of getting to space. Since then, SpaceX has found success with its <a href="https://www.spacex.com/vehicles/falcon-9/">Falcon 9</a> rocket and <a href="https://www.spacex.com/vehicles/dragon/">Dragon spacecraft</a>. SpaceX’s ultimate goal is human settlement of Mars; sending paying customers to space is an intermediate step. Musk says he hopes to show that space travel can be done easily and that tourism might provide a revenue stream to support development of the larger, Mars-focused Starship system.</p>
<p>Bezos, <a href="https://medium.com/@lynwerkledges/the-oneill-cylinder-jeff-bezos-vision-for-an-incredible-civilisation-in-space-fef75b499710">inspired by the vision of physicist Gerard O’Neill</a>, wants to expand humanity and industry not to Mars but to space itself. <a href="https://www.blueorigin.com/">Blue Origin</a>, established in 2004, has proceeded slowly and quietly in also developing reusable rockets. Its <a href="https://www.blueorigin.com/new-shepard/">New Shepard</a> rocket, first successfully flown in 2015, will be the spaceship taking tourists on suborbital trips to the edge of space <a href="https://www.reuters.com/lifestyle/science/blue-origin-begin-space-tourism-ticket-sales-wednesday-2021-05-05/">this July</a>. For Bezos, <a href="https://www.publicaffairsbooks.com/titles/christian-davenport/the-space-barons/9781610398305/">these launches represent</a> an effort at making space travel routine, reliable and accessible as a first step to enabling further space exploration.</p>
<figure class="align-center ">
<img alt="A large silvery rocket standing upright on a launchpad." src="https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.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">SpaceX has already started selling tickets to the public and has future plans to use its Starship rocket, a prototype of which is seen here, to send people to Mars.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Starship_SN9_Evening_Rays.jpg#/media/File:Starship_SN9_Evening_Rays.jpg">Jared Krahn/WikimediaCommons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Outlook for the future</h2>
<p>Blue Origin is not the only company offering passengers the opportunity to go into space and orbit the Earth. </p>
<p>SpaceX currently has two tourist launches planned. The first is <a href="https://spacenews.com/inspiration4-announces-crew-for-private-spacex-crew-dragon-mission/">scheduled for as early as September 2021</a>, funded by billionaire businessman Jared Isaacman. The other trip, planned for 2022, is <a href="https://www.cnbc.com/2021/01/26/axiom-space-unveils-ax-1-crew-for-fully-private-spacex-mission-to-iss.html">being organized by Axiom Space</a>. These trips <a href="https://www.nytimes.com/2020/03/05/science/axiom-space-station.html">will be costly</a> for wannabe space travelers, at $55 million for the flight and a stay on the International Space Station. The high cost has led some to warn that <a href="https://spacenews.com/foust-forward-space-tourisms-image-problem/">space tourism</a> – and private access to space more broadly – might reinforce inequality between rich and poor.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A white domed capsule with windows in the Texas desert." src="https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/399319/original/file-20210506-17-1dd96mg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The first tourist to fly on a privately owned spaceship will ride in Blue Origin’s New Shepard Crew Capsule, seen here after a test flight in Texas.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Blue_Origin_M7.jpg">NASA Flight Opportunities/WikimediaCommons</a></span>
</figcaption>
</figure>
<p>While Blue Origin is already accepting bids for a seat on the first launch, it has not yet announced the cost of a ticket for future trips. Passengers will also need to meet several physical qualifications, including weighing 110 to 223 pounds (50 to 101 kg) and measuring between 5 feet and 6 feet, 4 inches (1.5 to 1.9 meters) in height. Virgin Galactic, which continues to test SpaceShipTwo, has no specific timetable, but its tickets are expected to be <a href="https://www.cnbc.com/2020/09/26/space-tourism-how-spacex-virgin-galactic-blue-origin-axiom-compete.html">priced from $200,000 to $250,000</a>.</p>
<p>Though these prices are high, it is worth considering that Dennis Tito’s $20 million ticket in 2001 could potentially pay for 100 flights on Blue Origin soon. The experience of viewing the Earth from space, though, may prove to be priceless for a whole new generation of space explorers.</p>
<p><em>This is an updated version of an <a href="https://theconversation.com/space-tourism-20-years-in-the-making-is-finally-ready-for-launch-159606">article originally published</a> on April 28, 2021. It has been updated to include the announcement by Blue Origin.</em></p><img src="https://counter.theconversation.com/content/160510/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 Defense Department or any of its affiliates. </span></em></p>The first space tourist left Earth 20 years ago aboard a Russian rocket. Now, private companies like Jeff Bezos’ Blue Origin are offering trips to the stars for those who can pay.Wendy Whitman Cobb, Professor of Strategy and Security Studies, Air UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1596062021-04-28T12:15:09Z2021-04-28T12:15:09ZSpace tourism – 20 years in the making – is finally ready for launch<figure><img src="https://images.theconversation.com/files/397411/original/file-20210427-21-1cpclid.jpg?ixlib=rb-1.1.0&rect=414%2C176%2C6979%2C5759&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Space tourism has been slow to get off the ground. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/space-tourism-concept-a-young-male-asian-royalty-free-illustration/1300171457?adppopup=true">Nadia Bormotova/iStock via Getty Images Plus</a></span></figcaption></figure><p>For most people, getting to the stars is nothing more than a dream. On April 28, 2001, Dennis Tito achieved that lifelong goal – but he wasn’t a typical astronaut. Tito, a wealthy businessman, <a href="https://www.space.com/11492-space-tourism-pioneer-dennis-tito.html">paid US$20 million for a seat on a Russian Soyuz</a> spacecraft to be the first tourist to visit the International Space Station. Only <a href="https://spaceadventures.com/experiences/space-station/">seven people have followed suit</a> in the 20 years since, but that number is poised to double in the next 12 months alone.</p>
<p>NASA has long been <a href="http://www.spaceref.com/news/viewnews.html?id=304">hesitant to play host to space tourists</a>, so Russia – looking for sources of money post-Cold War in the 1990s and 2000s – has been the only option available for those looking for this kind of extreme adventure. However, it seems the rise of private space companies is going to make it easier for regular people to experience space.</p>
<p>From my perspective as <a href="https://scholar.google.com/citations?user=PxIOz7cAAAAJ&hl=en&oi=ao">a space policy analyst</a>, I see the beginning of an era in which more people can experience space. With companies like SpaceX and Blue Origin hoping to build a future for humanity in space, space tourism is a way to demonstrate both the safety and reliability of space travel to the general public.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Three men floating in the International Space Station" src="https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397415/original/file-20210427-21-1lvsrl9.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"></a>
<figcaption>
<span class="caption">Dennis Tito, on the left beside two Russian astronauts, was the first private citizen to ever go to space – and he spent more than a week on the International Space Station.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:ISS-02_Soyuz_TM-32_Taxi_crewmembers.jpg#/media/File:ISS-02_Soyuz_TM-32_Taxi_crewmembers.jpg">NASA/WikimediaCommons</a></span>
</figcaption>
</figure>
<h2>The development of space tourism</h2>
<p>Flights to space like Dennis Tito’s are expensive for a reason. A rocket must burn a lot of costly fuel to travel high and fast enough to enter Earth’s orbit. </p>
<p>Another cheaper possibility is a suborbital launch, with the rocket going high enough to reach the edge of space and coming right back down. While passengers on a suborbital trip experience weightlessness and incredible views, these launches are more accessible.</p>
<p>The difficulty and expense of either option has meant that, traditionally, only nation-states have been able to explore space. This began to change in the 1990s as a series of entrepreneurs entered the space arena. Three companies led by billionaire CEOs have emerged as the major players: Virgin Galactic, Blue Origin and SpaceX. Though none have taken paying, private customers to space, all anticipate doing so in the very near future.</p>
<p>British billionaire Richard Branson has built his brand on not just business but also his love of adventure. In pursuing space tourism, Branson has brought both of those to bear. He established <a href="https://www.virgingalactic.com/">Virgin Galactic</a> after buying <a href="https://www.space.com/16769-spaceshipone-first-private-spacecraft.html">SpaceShipOne</a> - a company that won the <a href="https://www.xprize.org/prizes/ansari">Ansari X-Prize</a> by building the first reusable spaceship. Since then, Virgin Galactic has sought to design, build and fly a larger <a href="https://www.virgingalactic.com/learn/">SpaceShipTwo</a> that can carry up to six passengers in a suborbital flight. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A silvery ship that looks like a fighter plane with elongated tail fins." src="https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=320&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=320&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=320&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=402&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=402&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397419/original/file-20210427-13-1cw14qm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=402&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 VSS Unity spacecraft is one of the ships that Virgin Galactic plans to use for space tours.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/VirginGalactic/c699fbc80ae44738a66a899dffd37b6a/photo?Query=virgin%20AND%20galactic&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=375&currentItemNo=13">AP Photo/Matt Hartman</a></span>
</figcaption>
</figure>
<p>The going has been harder than anticipated. While Branson <a href="http://news.bbc.co.uk/2/hi/science/nature/7529978.stm">predicted opening the business</a> to tourists in 2009, Virgin Galactic has encountered some significant hurdles – including the death of a pilot in <a href="https://www.space.com/30073-virgin-galactic-spaceshiptwo-crash-pilot-error.html">a crash in 2014</a>. After the crash, engineers found significant problems with the design of the vehicle, which required modifications.</p>
<p>Elon Musk and Jeff Bezos, respective leaders of SpaceX and Blue Origin, began their own ventures in the early 2000s.</p>
<p>Musk, <a href="https://www.space.com/spacex-starship-first-mars-trip-2024">fearing that a catastrophe</a> of some sort could leave Earth uninhabitable, was frustrated at the lack of progress in making humanity a multiplanetary species. He founded SpaceX in 2002 with the goal of first developing reusable launch technology to decrease the cost of getting to space. Since then, SpaceX has found success with its <a href="https://www.spacex.com/vehicles/falcon-9/">Falcon 9</a> rocket and <a href="https://www.spacex.com/vehicles/dragon/">Dragon</a> spacecraft. SpaceX’s ultimate goal is human settlement of Mars – sending paying customers to space is an intermediate step. Musk says he hopes to show that space travel can be done easily and that tourism might provide a revenue stream to support development of the larger, Mars-focused Starship system. </p>
<p>Bezos, <a href="https://medium.com/@lynwerkledges/the-oneill-cylinder-jeff-bezos-vision-for-an-incredible-civilisation-in-space-fef75b499710">inspired by the vision of physicist Gerard O’Neill</a>, wants to expand humanity and industry not to Mars, but to space itself. <a href="https://www.blueorigin.com/">Blue Origin</a>, established in 2004, has proceeded slowly and quietly in also developing reusable rockets. Its <a href="https://www.blueorigin.com/new-shepard/">New Shepard</a> rocket, first successfully flown in 2015, will eventually offer tourists a suborbital trip to the edge of space, similar to Virgin Galactic’s. For Bezos, <a href="https://www.publicaffairsbooks.com/titles/christian-davenport/the-space-barons/9781610398305/">these launches represent</a> an effort at making space travel routine, reliable and accessible to people as a first step to enabling further space exploration.</p>
<figure class="align-center ">
<img alt="A large silvery rocket standing upright on a launchpad." src="https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397422/original/file-20210427-21-1c0u725.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">SpaceX has already started selling tickets to the public and has future plans to use its Starship rocket, a prototype of which is seen here, to send people to Mars.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Starship_SN9_Evening_Rays.jpg#/media/File:Starship_SN9_Evening_Rays.jpg">Jared Krahn/WikimediaCommons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Outlook for the future</h2>
<p>Now, SpaceX is the only option for someone looking to go into space and orbit the Earth. It currently has two tourist launches planned. The first is <a href="https://spacenews.com/inspiration4-announces-crew-for-private-spacex-crew-dragon-mission/">scheduled for as early as September 2021</a>, funded by billionaire businessman Jared Isaacman. The other trip, planned for 2022, is <a href="https://www.cnbc.com/2021/01/26/axiom-space-unveils-ax-1-crew-for-fully-private-spacex-mission-to-iss.html">being organized by Axiom Space</a>. These trips <a href="https://www.nytimes.com/2020/03/05/science/axiom-space-station.html">will be costly</a>, at $55 million for the flight and a stay on the International Space Station. The high cost has led some to warn that <a href="https://spacenews.com/foust-forward-space-tourisms-image-problem/">space tourism</a> – and private access to space more broadly – might reinforce inequality between rich and poor.</p>
<p>Blue Origin’s and Virgin Galactic’s suborbital trips are far more reasonable in cost, with both <a href="https://www.cnbc.com/2020/09/26/space-tourism-how-spacex-virgin-galactic-blue-origin-axiom-compete.html">priced between $200,000 and $250,000</a>. Blue Origin appears to be the nearest to allowing paying customers on board, <a href="https://spacenews.com/blue-origin-aces-dress-rehearsal-for-new-shepard-crewed-flights/">saying after a recent launch</a> that crewed missions would be happening “soon.” Virgin Galactic continues to test SpaceShipTwo, but no specific timetable has been announced for tourist flights.</p>
<p>Though these prices are high, it is worth considering that Dennis Tito’s $20 million ticket in 2001 could pay for 100 flights on Blue Origin soon. The experience of viewing the Earth from space, though, may prove to be priceless for a whole new generation of space explorers.</p>
<p>[<em>Over 104,000 readers rely on The Conversation’s newsletter to understand the world.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=100Ksignup">Sign up today</a>.]</p>
<p><em>An updated version of this article was published on May 7, 2021. <a href="https://theconversation.com/space-tourism-is-here-20-years-after-the-first-stellar-tourist-jeff-bezos-blue-origin-plans-to-send-civilians-to-space-160510">Read it here</a>.</em></p><img src="https://counter.theconversation.com/content/159606/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 affiliates.</span></em></p>The first space tourist left Earth 20 years ago aboard a Russian rocket. Now, private companies are on the cusp of offering trips off Earth for those who can pay.Wendy Whitman Cobb, Professor of Strategy and Security Studies, Air UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1538512021-02-04T13:12:43Z2021-02-04T13:12:43ZBringing Mars rocks back to Earth: On Feb. 18, Perseverance Rover landed safely on Mars – a lead scientist explains the tech and goals<figure><img src="https://images.theconversation.com/files/385145/original/file-20210218-14-1pm2m5k.png?ixlib=rb-1.1.0&rect=191%2C13%2C672%2C440&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Perseverance Rover's first image sent back to NASA from Mars shows the surface of the Jezero crater.</span> <span class="attribution"><a class="source" href="https://www.nasa.gov/press-release/touchdown-nasas-mars-perseverance-rover-safely-lands-on-red-planet">NASA/JPL</a></span></figcaption></figure><p><em>Editor’s note: On Feb. 18, NASA’s <a href="https://mars.nasa.gov/mars2020/">Mars 2020 mission</a> arrived at the red planet and successfully landed the Perseverance Rover on the surface. <a href="https://scholar.google.com/citations?user=KR2ejsUAAAAJ&hl=en&oi=sra">Jim Bell</a> is a professor in the School of Earth and Space Exploration at Arizona State University and has worked on a number of Mars missions. He is the primary investigator leading a team in charge of one of the camera systems on Perseverance. We spoke with him in late January for The Conversation’s new podcast, <a href="https://theconversation.com/why-its-a-big-month-for-mars-the-conversation-weekly-podcast-154326">The Conversation Weekly</a>.</em></p>
<iframe src="https://player.acast.com/60087127b9687759d637bade/episodes/a-big-month-for-mars?theme=default&cover=1&latest=1" frameborder="0" width="100%" height="110px" allow="autoplay"></iframe>
<p><em>Below are excerpts from our conversation that have been edited for length and clarity.</em></p>
<h2>What’s the goal of this mission?</h2>
<p>What we’re looking for is evidence of past life, either direct chemical or organic signs in the composition and the chemistry of rocks, or textural evidence in the rock record. The environment of Mars is extremely harsh compared to the Earth, so we’re not really looking for evidence of current life. Unless something actually gets up and walks in front of the cameras, we’re really not going to find that.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A topographic, top down photo with colors showing the ancient river delta in the Jezero Crater" src="https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=481&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=481&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=481&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=604&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=604&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382059/original/file-20210202-21-xtkpmh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=604&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 color–enhanced photo shows the ancient river delta in the Jezero Crater where Perseverance will look for signs of life.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/w/index.php?search=jezero+crater+delta&title=Special:Search&go=Go&ns0=1&ns6=1&ns12=1&ns14=1&ns100=1&ns106=1&searchToken=8mo5vr95t586fpr7e67m1ighw#%2Fmedia%2FFile%3A260184-JezeroCrater-Delta-Full.jpg">NASA/JPL/JHU-APL/MSSS/Brown University</a></span>
</figcaption>
</figure>
<h2>Where is the Perseverance Rover landing to look for ancient life?</h2>
<p>There was a three- or four-year process that involved the entire global community of Mars and planetary science researchers to figure out where to send this rover. We chose a <a href="https://en.wikipedia.org/wiki/Jezero_(crater)">crater called Jezero</a>. Jezero has a beautiful river delta in it, preserved from an ancient river that flowed down into that crater and deposited sediments. This is kind of like the delta at the end of the Mississippi River in Louisiana which is depositing sediments very gently into the Gulf of Mexico.</p>
<p>On Earth, this shallow water is a very gentle environment where organic molecules and fossils can actually be gently buried and preserved in very fine-grained <a href="https://en.wikipedia.org/wiki/Mudstone">mudstones</a>. If a Martian delta operates the same way, then it’s a great environment for preserving evidence of things that were flowing in that water that came from the ancient highlands above the crater. </p>
<p>There’s lots of things we don’t know, but there was liquid water there. There were heat sources – there were active volcanoes 2, 3, 4 billion years ago on Mars – and there are impact craters from asteroids and comets dumping lots of heat into the ground as well as organic molecules. It’s a very short list of places in the solar system that meet those constraints, and Jezero is one of those places. It’s one of the best places that we think to go to do this search for life.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&rect=86%2C135%2C6745%2C5327&q=45&auto=format&w=1000&fit=clip"><img alt="The Perseverance Rover in a NASA lab on earth." src="https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&rect=86%2C135%2C6745%2C5327&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382056/original/file-20210202-15-17clle0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Perseverance Rover is 90% spare parts from the Curiosity Rover but has a few new tools on board.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Perseverance_(rover)#/media/File:PIA23499-Mars2020Rover-FirstTestDrive-20191217a.jpg">NASA/JPL-Caltech</a></span>
</figcaption>
</figure>
<h2>What scientific tools is Perseverance carrying?</h2>
<p>The <a href="https://mars.nasa.gov/mars2020/spacecraft/rover/">Perseverance Rover</a> looks a lot like <a href="https://mars.nasa.gov/msl/home/">Curiosity</a> on the outside because it’s made from something like 90% spare parts from Curiosity – that’s how NASA could afford this mission. Curiosity has a pair of cameras – one wide angle, one telephoto.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The Mastcam-Z cameras side by side. They are cylindrical, copper colored tubes with square lenses." src="https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=374&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=374&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=374&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=470&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=470&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382063/original/file-20210202-21-1uivdco.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=470&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Mastcam-Z includes two cameras with zoom lenses allowing researchers to create three-dimensional images of the Martian landscape.</span>
<span class="attribution"><a class="source" href="https://mars.nasa.gov/resources/25282/ready-for-a-close-up-or-a-wide-angle/">MSSS/ASU</a></span>
</figcaption>
</figure>
<p>In Perseverance, we’re sending similar cameras, but with zoom technology so we can zoom from wide angle to telephoto with both cameras – the “Z” in <a href="https://mars.nasa.gov/mars2020/spacecraft/instruments/mastcam-z/">Mastcam-Z</a> stands for zoom. This allows us to get great stereo images. Just like our left eye and our right eye build a three-dimensional image in our brain, the zoom cameras on Perserverance are a left eye and a right eye. With this, we can build a three-dimensional image back on Earth when we get those images.</p>
<p>3D images allow us to do a whole range of things scientifically. We want to understand the topography of Mars in much more detail than we’ve been able to in the past. We want to put the pieces of the delta geology story together not just with two-dimensional, spatial information, but with height as well as texture. And we want to make 3D maps of the landing site. </p>
<p>Our engineering and driving colleagues really need that information too. These 3D images will help them decide where to drive by helping to identify obstacles and slopes and trenches and rocks and stuff like that, allowing them to drive the rover much deeper into places than they would have been able to otherwise.</p>
<p>And finally, we’re going to make really cool 3D views of our landing site to share with the public, including movies and flyovers.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing the sample collection tubes which are made from titanium and include a sealing mechanism." src="https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/382064/original/file-20210202-21-1h5xf7o.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">The sample tubes are specially built to store the rock and soil cores for future pickup.</span>
<span class="attribution"><a class="source" href="https://mars.nasa.gov/resources/25483/anatomy-of-a-sample-tube-interior/">NASA/JPL-Caltech</a></span>
</figcaption>
</figure>
<h2>What else is different about this mission?</h2>
<p>Perseverance is intended to be the first part of a robotic sample return mission from Mars. So instead of just drilling into the surface like the Curiosity Rover does, Perseverance will drill and core into the surface and <a href="https://mars.nasa.gov/mars2020/mission/science/objectives/">cache those little cores into tubes</a> about the size of a dry-erase marker. It will then put those tubes onto the surface for a future mission later this decade to pick up and then bring back to the Earth. </p>
<p>Perseverance won’t come back to the Earth, but the plan is to bring the samples that we collect back.</p>
<p>In the meantime, we’ll be doing all of the science that any great rover mission would do. We are going to characterize the site, explore the geology and measure the atmospheric and weather properties. </p>
<p>[<em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>.]</p>
<h2>How will you get those samples back to Earth?</h2>
<p>This is where it gets a little less certain, because these are all ideas and missions in the works. NASA and the European Space Agency are collaborating on a concept to build and launch a lander that will send a little fetch rover that goes and gets the little tubes, picks them up and brings them back to the lander. Waiting on the lander would be a small rocket called a <a href="https://mars.nasa.gov/resources/24764/mars-ascent-vehicle-launching-with-samples-artists-concept/">Mars Ascent Vehicle</a>, or MAV. Once the samples are loaded into the MAV, it launches them into Mars orbit.</p>
<p>Then you’ve got this grapefruit- to soccer-ball-sized canister up there, and NASA and the Europeans are collaborating on an orbiter that will search for that canister, capture it and then rocket it back to the Earth, where it will land in the Utah desert. What could possibly go wrong?</p>
<p>If successful, that’ll be the first time we’ve done that from Mars. The scientific tools on the rovers are good, but nothing like the labs back on Earth. Bringing those samples back is going to be absolutely critical to getting the most out of the samples.</p>
<p><em>This is an updated version of an article originally published on Feb. 4. The editor’s note was updated to reflect the successful landing of the Perseverance Rover on Mars.</em></p><img src="https://counter.theconversation.com/content/153851/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jim Bell receives funding from NASA for his work on the Perseverance rover mission.. He is also an unpaid member of the Board of Directors of The Planetary Society, engaging in activities including education and advocacy of space exploration with elected officials.</span></em></p>NASA’s Mars 2020 mission has arrived and landed the Perseverance Rover on the red planet. The rover’s goal is to collect rock and soil samples to be brought back to Earth in the future.Jim Bell, Professor of Earth and Space Exploration, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1501672020-12-20T21:12:25Z2020-12-20T21:12:25ZHow to get people from Earth to Mars and safely back again<figure><img src="https://images.theconversation.com/files/372184/original/file-20201201-21-qplwcp.jpg?ixlib=rb-1.1.0&rect=758%2C353%2C1158%2C724&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://images.nasa.gov/details-PIA24032">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>There are many things humanity must overcome before any return journey to Mars is launched.</p>
<p>The two major players are NASA and SpaceX, which work together intimately on missions to the International Space Station but have competing ideas of what a crewed Mars mission would look like.</p>
<h2>Size matters</h2>
<p>The biggest challenge (or constraint) is the mass of the payload (spacecraft, people, fuel, supplies etc) needed to make the journey.</p>
<p>We still talk about launching something into space being like launching its weight in gold.</p>
<p>The payload mass is usually just a small percentage of the total mass of the launch vehicle.</p>
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Read more:
<a href="https://theconversation.com/buried-lakes-of-salty-water-on-mars-may-provide-conditions-for-life-146928">Buried lakes of salty water on Mars may provide conditions for life</a>
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</em>
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<p>For example, the <a href="https://solarsystem.nasa.gov/news/382/10-things-rockets-we-love-saturn-v/">Saturn V</a> rocket that launched <a href="https://www.nasa.gov/mission_pages/apollo/apollo-11.html">Apollo 11</a> to the Moon weighed 3,000 tonnes.</p>
<p>But it could launch only 140 tonnes (5% of its initial launch mass) to low Earth orbit, and 50 tonnes (less than 2% of its initial launch mass) to the Moon.</p>
<p>Mass constrains the size of a Mars spacecraft and what it can do in space. Every manoeuvre costs fuel to fire rocket motors, and this fuel must currently be carried into space on the spacecraft.</p>
<p>SpaceX’s plan is for its crewed <a href="https://www.spacex.com/vehicles/starship/">Starship</a> vehicle to be <a href="https://spaceflightnow.com/2020/10/16/nasa-selects-companies-to-demonstrate-in-space-refueling-and-propellant-depot-tech/">refuelled in space</a> by a separately launched fuel tanker. That means much more fuel can be carried into orbit than could be carried on a single launch.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A rocket capsule just about to land on Mars." src="https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/374113/original/file-20201210-18-15bl8cf.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">Concept art of SpaceX’s Dragon landing on Mars.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/spacex/21424800115/">Official SpaceX Photos/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<h2>Time matters</h2>
<p>Another challenge, intimately connected with fuel, is time.</p>
<p>Missions that send spacecraft with no crew to the outer planets often travel complex trajectories around the Sun. They use what are called <a href="https://solarsystem.nasa.gov/basics/primer/">gravity assist manoeuvres</a> to effectively slingshot around different planets to gain enough momentum to reach their target.</p>
<p>This saves a lot of fuel, but can result in missions that take years to reach their destinations. Clearly this is something humans would not want to do. </p>
<p>Both Earth and Mars have (almost) circular orbits and a manoeuvre known as the <a href="https://solarsystem.nasa.gov/basics/chapter4-1/">Hohmann transfer</a> is the most fuel-efficient way to travel between two planets. Basically, without going into too much detail, this is where a spacecraft does a single burn into an elliptical transfer orbit from one planet to the other.</p>
<p>A Hohmann transfer between Earth and Mars takes around 259 days (between eight and nine months) and is only possible approximately every two years due to the different orbits around the Sun of Earth and Mars.</p>
<p>A spacecraft could reach Mars in a shorter time (SpaceX is claiming <a href="https://www.space.com/spacex-plans-journey-to-mars.html">six months</a>) but — you guessed it — it would cost more fuel to do it that way.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3361%2C2212&q=45&auto=format&w=1000&fit=clip"><img alt="Mars, the red planet." src="https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3361%2C2212&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372132/original/file-20201201-13-1s1mkcn.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">Mars and Earth have few similarities.</span>
<span class="attribution"><a class="source" href="https://solarsystem.nasa.gov/resources/683/valles-marineris-the-grand-canyon-of-mars/">NASA/JPL-Caltech</a></span>
</figcaption>
</figure>
<h2>Safe landing</h2>
<p>Suppose our spacecraft and crew get to Mars. The next challenge is landing.</p>
<p>A spacecraft entering Earth is able to use the drag generated by interaction with the atmosphere to slow down. This allows the craft to land safely on the Earth’s surface (provided it can survive the related heating).</p>
<p>But the atmosphere on Mars is about 100 times thinner than Earth’s. That means less potential for drag, so it isn’t possible to land safely without some kind of aid. </p>
<p>Some missions have landed on airbags (such as NASA’s <a href="https://mars.nasa.gov/mars-exploration/missions/pathfinder/">Pathfider</a> mission) while others have used thrusters (NASA’s <a href="https://www.nasa.gov/mission_pages/phoenix/overview">Phoenix</a> mission). The latter, once again, requires more fuel.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/5TaP8YMM524?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A thruster landing on Mars.</span></figcaption>
</figure>
<h2>Life on Mars</h2>
<p>A Martian day lasts 24 hours and 37 minutes but the similarities with Earth stop there.</p>
<p>The thin atmosphere on Mars means it can’t retain heat as well as Earth does, so life on Mars is characterised by large extremes in temperature during the day/night cycle.</p>
<p>Mars has a maximum temperature of 30°C, which sounds quite pleasant, but its minimum temperature is -140°C, and its average temperature is <a href="https://mars.nasa.gov/all-about-mars/facts/">-63°C</a>. The average winter temperature at the Earth’s South Pole is <a href="https://niwa.co.nz/education-and-training/schools/resources/climate/antarctic">about -49°C</a>.</p>
<p>So we need to be very selective about where we choose to live on Mars and how we manage temperature during the night.</p>
<p>The gravity on Mars is 38% of Earth’s (so you’d feel lighter) but the air is principally carbon dioxide (CO₂) with several percent of nitrogen, so it’s completely unbreathable. We would need to build a climate-controlled place just to live there.</p>
<p>SpaceX <a href="https://www.spacex.com/human-spaceflight/mars/">plans</a> to <a href="https://www.space.com/spacex-plans-journey-to-mars.html">launch several cargo flights</a> including critical infrastructure such as greenhouses, solar panels and — you guessed it — a fuel-production facility for return missions to Earth.</p>
<p>Life on Mars would be possible and several simulation <a href="https://theconversation.com/dear-diary-the-sun-never-set-on-the-arctic-mars-simulation-84597">trials</a> have <a href="https://www.bbc.com/news/world-us-canada-34092770">already</a> been <a href="https://www.nationalgeographic.com/science/2019/01/see-how-astronauts-simulate-mars-mission-on-earth/">done</a> on Earth to see how people would cope with such an existence.</p>
<h2>Return to Earth</h2>
<p>The final challenge is the return journey and getting people safely back to Earth.</p>
<p>Apollo 11 entered Earth’s atmosphere at about 40,000km/h, which is just below the velocity required to escape Earth’s orbit.</p>
<p>Spacecraft returning from Mars will have re-entry velocities from 47,000km/h to 54,000km/h, depending on the orbit they use to arrive at Earth.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dear-diary-the-sun-never-set-on-the-arctic-mars-simulation-84597">Dear diary: the Sun never set on the Arctic Mars simulation</a>
</strong>
</em>
</p>
<hr>
<p>They could slow down into low orbit around Earth to around 28,800km/h before entering our atmosphere but — you guessed it — they’d need extra fuel to do that.</p>
<p>If they just barrel into the atmosphere, it will do all of the deceleration for them. We just need to make sure we don’t kill the astronauts with G-forces or burn them up due to excess heating.</p>
<p>These are just some of the challenges facing a Mars mission and all of the technological building blocks to achieve this are there. We just need to spend the time and the money and bring it all together.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The view of sunrise over Earth as seen from the International Space Station" src="https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/374120/original/file-20201210-23-xkn5nb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">And we need to return people safely back to Earth, mission accomplished.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/image-feature/good-morning-from-the-international-space-station-1">NASA</a></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/150167/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris James receives funding from the Australian Research Council. </span></em></p>We’ve already sent probes to land on Mars. The challenge now is to get people there and bring them home again.Chris James, Lecturer, Centre for Hypersonics, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1379672020-05-20T12:15:15Z2020-05-20T12:15:15ZTo safely explore the solar system and beyond, spaceships need to go faster – nuclear-powered rockets may be the answer<figure><img src="https://images.theconversation.com/files/335879/original/file-20200518-83367-yrk119.jpg?ixlib=rb-1.1.0&rect=0%2C17%2C3952%2C3119&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Over the last 50 years, a lot has changed in rocketry. The fuel that powers spaceflight might finally be changing too. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/rocket-orbiting-the-earth-royalty-free-illustration/533327609?adppopup=true">CSA-Printstock/DIgital Vision Vectors via Getty Images</a></span></figcaption></figure><p>With dreams of Mars on the minds <a href="https://www.nasa.gov/topics/moon-to-mars/lunar-gateway">of both NASA</a> and <a href="https://www.vox.com/2018/11/2/18053424/elon-musk-tesla-spacex-boring-company-self-driving-cars-saudi-twitter-kara-swisher-decode-podcast">Elon Musk</a>, long-distance crewed missions through space are coming. But you might be surprised to learn that modern rockets don’t go all that much faster than the rockets of the past.</p>
<p>There are a lot of reasons that a faster spaceship is a better one, and nuclear-powered rockets are a way to do this. They offer many benefits over traditional fuel-burning rockets or modern solar-powered electric rockets, but there have been only <a href="https://www.energy.gov/ne/nuclear-reactor-technologies/space-power-systems/next-generation-radioisotope-generators">eight U.S. space launches</a> carrying nuclear reactors in the last 40 years.</p>
<p>However, in 2019 the <a href="https://www.space.com/trump-nuclear-spacecraft-launch-guidelines.html">laws regulating nuclear space flights changed</a> and work has already begun on this next generation of rockets. </p>
<h2>Why the need for speed?</h2>
<p>The first step of a space journey involves the use of launch rockets to get a ship into orbit. These are the large fuel-burning engines people imagine when they think of rocket launches and are not likely to go away in the foreseeable future due to the constraints of gravity.</p>
<p>It is once a ship reaches space that things get interesting. To escape Earth’s gravity and reach deep space destinations, ships need additional acceleration. This is where nuclear systems come into play. If astronauts want to explore anything farther than the Moon and perhaps Mars, they are going to need to be going very very fast. Space is <a href="https://www.youtube.com/watch?v=Iy7NzjCmUf0&t=178s">massive</a>, and <a href="https://www.youtube.com/watch?v=zR3Igc3Rhfg">everything is far away</a>.</p>
<p>There are two reasons faster rockets are better for long-distance space travel: safety and time.</p>
<p>Astronauts on a trip to Mars would be <a href="https://www.space.com/41887-mars-radiation-too-much-for-astronauts.html">exposed to very high levels of radiation</a> which can cause serious <a href="https://www.asc-csa.gc.ca/eng/sciences/osm/radiation.asp">long-term health problems such as cancer and sterility</a>. Radiation shielding can help, but it is extremely heavy, and the longer the mission, the more shielding is needed. A better way to reduce radiation exposure is to simply get where you are going quicker.</p>
<p>But human safety isn’t the only benefit. As space agencies probe farther out into space, it is important to get data from unmanned missions as soon as possible. It took <a href="https://voyager.jpl.nasa.gov/mission/science/neptune/">Voyager-2 12 years just to reach Neptune</a>, where it snapped some incredible photos as it flew by. If Voyager-2 had a faster propulsion system, astronomers could have had those photos and the information they contained years earlier. </p>
<p>Speed is good. But why are nuclear systems faster?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=487&fit=crop&dpr=1 600w, https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=487&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=487&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=613&fit=crop&dpr=1 754w, https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=613&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/335875/original/file-20200518-83367-1x6b8r7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=613&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Saturn V rocket was 363 feet tall and mostly just a gas tank.</span>
<span class="attribution"><a class="source" href="http://heroicrelics.org/info/saturn-v/saturn-v-general.html">Mike Jetzer/heroicrelics.org</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>Systems of today</h2>
<p>Once a ship has escaped Earth’s gravity, there are three important aspects to consider when comparing any propulsion system:</p>
<ul>
<li>Thrust – how fast a system can accelerate a ship</li>
<li>Mass efficiency – how much thrust a system can produce for a given amount of fuel</li>
<li>Energy density – how much energy a given amount of fuel can produce</li>
</ul>
<p>Today, the most common propulsion systems in use are chemical propulsion – that is, regular fuel-burning rockets – and solar-powered electric propulsion systems.</p>
<p><a href="https://www.grc.nasa.gov/www/k-12/airplane/rocket.html">Chemical propulsion systems</a> provide a lot of thrust, but chemical rockets aren’t particularly efficient, and rocket fuel isn’t that energy-dense. The Saturn V rocket that took astronauts to the Moon produced <a href="https://en.wikipedia.org/wiki/Saturn_V#cite_note-30">35 million Newtons of force</a> at liftoff and <a href="https://www.space.com/18422-apollo-saturn-v-moon-rocket-nasa-infographic.html">carried 950,000 gallons of fuel</a>. While most of the fuel was used in getting the rocket into orbit, the limitations are apparent: It takes a lot of heavy fuel to get anywhere.</p>
<p>Electric propulsion systems generate thrust using electricity produced from solar panels. The most common way to do this is to use an electrical field to accelerate ions, such as in the <a href="https://www.grc.nasa.gov/WWW/hall/overview/overview.htm">Hall thruster</a>. These devices are <a href="https://www.nasa.gov/pdf/501329main_TA02-ID_rev3-NRC-wTASR.pdf">commonly used to power satellites</a> and can have more than five times higher mass efficiency than chemical systems. But they produce much less thrust – <a href="https://www.grc.nasa.gov/WWW/hall/overview/overview.htm">about three Newtons</a>, or only enough to accelerate a car from 0-60 mph in about two and a half hours. The energy source – the Sun – is essentially infinite but becomes less useful the farther away from the Sun the ship gets.</p>
<p>One of the reasons nuclear-powered rockets are promising is because they offer incredible energy density. The uranium fuel used in nuclear reactors has an energy density that is <a href="https://en.wikipedia.org/wiki/Energy_density">4 million times higher</a> than hydrazine, a typical chemical rocket propellant. It is much easier to get a small amount of uranium to space than hundreds of thousands of gallons of fuel.</p>
<p>So what about thrust and mass efficiency?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=477&fit=crop&dpr=1 600w, https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=477&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=477&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=600&fit=crop&dpr=1 754w, https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=600&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/335877/original/file-20200518-83348-1mwpqh4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=600&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 first nuclear thermal rocket was built in 1967 and is seen in the background. In the foreground is the protective casing that would hold the reactor.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Nuclear_thermal_rocket#/media/File:NERVA_XE_nuclear_rocket_engine_being_transported_to_test_stand_-_GPN-2002-000143.jpg">NASA/Wikipedia</a></span>
</figcaption>
</figure>
<h2>Two options for nuclear</h2>
<p>Engineers have designed two main types of nuclear systems for space travel. </p>
<p>The first is called <a href="https://www.nasa.gov/directorates/spacetech/game_changing_development/Nuclear_Thermal_Propulsion_Deep_Space_Exploration">nuclear thermal propulsion</a>. These systems are very powerful and moderately efficient. They use a small nuclear fission reactor – similar to those found in nuclear submarines – to heat a gas, such as hydrogen, and that gas is then accelerated through a rocket nozzle to provide thrust. Engineers from NASA estimate that a mission to Mars powered by nuclear thermal propulsion would be <a href="https://www.popularmechanics.com/space/moon-mars/a18345717/nasa-ntp-nuclear-engines-mars/">20%-25% shorter than a trip on a chemical-powered rocket</a>. </p>
<p>Nuclear thermal propulsion systems are more than <a href="https://www.energy.gov/ne/articles/6-things-you-should-know-about-nuclear-thermal-propulsion">twice as efficient as chemical propulsion systems</a> – meaning they generate twice as much thrust using the same amount of propellant mass – and can deliver <a href="https://gameon.nasa.gov/gcd/files/2018/02/FS_NTP_180213.pdf">100,000 Newtons of thrust</a>. That’s enough force to get a car from 0-60 mph in about a quarter of a second.</p>
<p>The second nuclear-based rocket system is called nuclear electric propulsion. <a href="https://www.nasa.gov/directorates/spacetech/niac/2019_Phase_I_Phase_II/SPEAR_Probe/">No nuclear electric systems have been built yet</a>, but the idea is to use a high-power fission reactor to generate electricity that would then power an electrical propulsion system like a Hall thruster. This would be very efficient, about <a href="https://www.popularmechanics.com/space/moon-mars/a18345717/nasa-ntp-nuclear-engines-mars/">three times better than a nuclear thermal propulsion system</a>. Since the nuclear reactor could create a lot of power, many individual electric thrusters could be operated simultaneously to generate a good amount of thrust. </p>
<p>Nuclear electric systems would be the best choice for extremely long-range missions because they don’t require solar energy, have very high efficiency and can give relatively high thrust. But while nuclear electric rockets are extremely promising, there are still a lot of <a href="https://www.nasa.gov/directorates/spacetech/niac/2019_Phase_I_Phase_II/SPEAR_Probe/">technical problems to solve</a> before they are put into use. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/335876/original/file-20200518-83393-1ygu5b7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An artist’s impression of what a nuclear thermal ship built to take humans to Mars could look like.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Nuclear_thermal_rocket#/media/File:Orion_docked_to_Mars_Transfer_Vehicle.jpg">John Frassanito & Associates/Wikipedia</a></span>
</figcaption>
</figure>
<h2>Why aren’t there nuclear powered rockets yet?</h2>
<p>Nuclear thermal propulsion systems have been studied since the 1960s but have not yet flown in space. </p>
<p><a href="https://aerospace.csis.org/wp-content/uploads/2019/02/NSC-25-Scientific-or-Technological-Experiements-with-Possible-Large-Scale-Adverse-Environmental-Effects-and-Launch-of-Nuclear-Weapons-into-Space.pdf">Regulations</a> first imposed in the U.S. in the 1970s essentially required case-by-case examination and approval of any nuclear space project from multiple government agencies and explicit approval from the president. Along with a <a href="https://www.csis.org/analysis/what-does-trump-administrations-new-memorandum-mean-nuclear-powered-space-missions">lack of funding for nuclear rocket system research</a>, this environment prevented further improvement of nuclear reactors for use in space. </p>
<p>That all changed when the Trump administration issued a <a href="https://www.whitehouse.gov/presidential-actions/presidential-memorandum-launch-spacecraft-containing-space-nuclear-systems/">presidential memorandum</a> in August 2019. While upholding the need to keep nuclear launches as safe as possible, the new directive allows for nuclear missions with lower amounts of nuclear material to <a href="https://www.csis.org/analysis/what-does-trump-administrations-new-memorandum-mean-nuclear-powered-space-missions">skip the multi-agency approval process</a>. Only the sponsoring agency, like NASA, for example, needs to certify that the mission meets safety recommendations. Larger nuclear missions would go through the same process as before.</p>
<p>Along with this revision of regulations, <a href="https://spacenews.com/final-fiscal-year-2019-budget-bill-secures-21-5-billion-for-nasa/">NASA received US$100 million in the 2019 budget</a> to develop nuclear thermal propulsion. DARPA is also developing a <a href="https://breakingdefense.com/2020/02/darpa-doubles-dough-for-nuclear-powered-cislunar-rocket/">space nuclear thermal propulsion system</a> to enable national security operations beyond Earth orbit. </p>
<p>After 60 years of stagnation, it’s possible a nuclear-powered rocket will be heading to space within a decade. This exciting achievement will usher in a new era of space exploration. People will go to Mars and science experiments will make new discoveries all across our solar system and beyond.</p>
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<p class="fine-print"><em><span>Iain Boyd receives funding from the following sources, none of it is related to space propulsion:
Office of Naval Research
Lockheed-Martin
Northrop-Grumman
L3-Harris</span></em></p>An update of 50-year-old regulations has kickstarted research into the next generation of rockets. Powered by nuclear fission, these new systems could be the key to faster, safer exploration of space.Iain Boyd, Professor of Aerospace Engineering Sciences, University of Colorado BoulderLicensed as Creative Commons – attribution, no derivatives.