tag:theconversation.com,2011:/id/topics/panspermia-7266/articlesPanspermia – The Conversation2016-10-07T06:56:18Ztag:theconversation.com,2011:article/655682016-10-07T06:56:18Z2016-10-07T06:56:18ZTo boldly go toward new frontiers, we first need to learn from our colonial past<figure><img src="https://images.theconversation.com/files/140834/original/image-20161007-32698-8dgk2y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The idea that there's a moral imperative for humans to expand beyond Earth is echoed by influential proponents of space exploration. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/tamaracraiu/4504728673/">Tamara Craiu/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>How should we understand the idea of the frontier in the contemporary world, with spacecraft sailing <a href="http://voyager.jpl.nasa.gov/where/">beyond the solar system</a> and <a href="https://en.wikipedia.org/wiki/Quantum_computing">quantum computing</a> taking us deeper into the heart of matter?</p>
<p>Many view human evolution as a continual expansion into new territories, from out-of-Africa to the “high frontier” of space. Frontiers, then, are associated with exploration, conquest, and struggles against hostile nature. </p>
<p>They can be seen as a challenge to solve with technology, going hand-in-hand with human progress. But the concept also comes with a lot of baggage. </p>
<h2>From stone age to space age?</h2>
<p>Once upon a time, the story goes, the world was full of space for humans to expand into. The genus <em>Homo</em> radiated <a href="http://phys.org/news/2016-09-human-dna-tied-exodus-africa.html">out from temperate Africa</a>, colonising the tundras of Ice Age Europe, and the continents and islands of Asia and Australasia. </p>
<p>As the climate warmed from 12,000 years ago, populations increased and people with domesticated animals and crops expanded further, turning <a href="https://news.virginia.edu/content/agricultural-methods-early-civilizations-may-have-altered-global-climate-study-suggests">forests into fields</a> along the way.</p>
<p>On one side of the frontier was tame “culture”; on the other wild “nature”. Humans proved tremendously successful at adapting to these new environments using technologies such as fire, stone tools and metallurgy. </p>
<p>By the 20th century, technology had enabled humans to move beyond the narrow band of pressure and temperature where our bodies had evolved, to explore the deep sea, the Earth’s poles, and outer space. Special suits and vehicles enabled travel to these remote places where life at the extremes promised revelations about our place in the universe.</p>
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<p>This story is captured well in a famous scene from the 1968 film <em><a href="http://www.imdb.com/title/tt0062622/">2001: A Space Odyssey</a></em> in which a bone tool, flung into the sky by an ancestral being, is transformed into an Earth-orbiting spacecraft. </p>
<h2>The other side of the frontier</h2>
<p>What’s often left out of this popular narrative is the perspective of those on the other side of the frontier. Consider colonial expansion from the 15th century onwards, when European nations sent ships to the southern hemisphere in search of new resources. </p>
<p>European invaders painted Indigenous people as Stone Age “savages” and cast themselves as the pinnacle of human evolution, entitled to lay claim to <a href="https://en.wikipedia.org/wiki/Terra_incognita">terra incognita</a> and <a href="https://en.wikipedia.org/wiki/Terra_nullius">terra nullius</a>. </p>
<p>The conquest of frontiers in the American West, the Australian outback, South America and numerous other places, was often brutal and bloody. The expanding front didn’t bring “civilisation” to supposedly benighted people; the result was rather <a href="http://www.australianstogether.org.au/stories/detail/colonisation">genocide, disease, environmental degradation, alienation and poverty</a>.</p>
<p>Utopia did not lie waiting in the New World. </p>
<p>Yet, despite the weight of historical evidence, people continue to assume that new frontiers beyond the Earth can <a href="http://www.independent.co.uk/news/science/stephen-hawking-space-travel-will-save-mankind-and-we-should-colonise-other-planets-10058811.html">provide refuge</a> from old injustices perpetuated on this planet.</p>
<h2>Panspermia and the moral imperative</h2>
<p><a href="https://en.wikipedia.org/wiki/Panspermia">Panspermia</a> is the theory that the universe is filled with life. Micro-organisms and pre-biotic molecules travel on comets and asteroids between the worlds, flourishing when and where conditions are right.</p>
<p>The expansion of life into every available niche is thought to be a natural process that’s taken place countless times in this, and other, galaxies. The corollary of this idea is that enabling the spread of human life throughout the universe is justified.</p>
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<img alt="" src="https://images.theconversation.com/files/140833/original/image-20161007-32718-1sndeuf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/140833/original/image-20161007-32718-1sndeuf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=469&fit=crop&dpr=1 600w, https://images.theconversation.com/files/140833/original/image-20161007-32718-1sndeuf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=469&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/140833/original/image-20161007-32718-1sndeuf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=469&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/140833/original/image-20161007-32718-1sndeuf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=589&fit=crop&dpr=1 754w, https://images.theconversation.com/files/140833/original/image-20161007-32718-1sndeuf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=589&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/140833/original/image-20161007-32718-1sndeuf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=589&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">The trappings of status in the ‘real’ world are just a matter of coding in the virtual one.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/andreasstawinski/15568818582/">Cyber-Andi/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>To date, evidence that micro-organisms can survive journeys in space, even if encased in meteoroids, is scant. Critics also point out that the theory merely delays the real question, which is how life started. </p>
<p>While the panspermia theory is controversial, the idea that there’s a moral imperative for humans to expand beyond Earth is echoed by <a href="http://www.spacequotes.com/">influential proponents</a> of space exploration. </p>
<p>Consider <a>these thoughts</a>) from American science fiction writer <a href="http://www.raybradbury.com/">Ray Bradbury</a>, from his 1971 conversation with <a href="http://www.carlsagan.com/">Carl Sagan</a>, and <a href="http://www.biography.com/people/arthur-c-clarke-9249620">Arthur C. Clarke</a>, on the eve of NASA’s Mariner 9 spacecraft entering orbit around Mars:</p>
<blockquote>
<p>What’s the use of looking at Mars through a telescope, sitting on panels, writing books, if it isn’t to guarantee, not just the survival of mankind, but mankind surviving forever!</p>
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<p>And here’s space-travel advocate, <a href="https://en.wikipedia.org/wiki/Marshall_Savage">Marshall Savage</a> in his 1992 book <a href="https://www.goodreads.com/book/show/1965968.The_Millennial_Project?from_search=true">The Millennial Project: Colonising the Galaxy in Eight Easy Steps</a>: </p>
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<p>We need to rupture the barriers that confine us to the land mass of a single planet. By breaking out, we can assure our survival and the continuation of Life.</p>
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<p>Such views are increasingly attracting trenchant criticism, as scholars “<a href="https://theconversation.com/want-to-understand-the-decolonisation-debate-heres-your-reading-list-51279">decolonise</a>” knowledge and expose how the simple narrative of frontier expansion obscures the cause of terrestrial inequalities.</p>
<h2>Islands of the interior</h2>
<p>Perhaps the frontiers to be conquered in the 21st century are not spatial, but virtual. </p>
<p>Rapid advances in computing technology and data storage have renewed speculation about the idea, so often described in science fiction, of <a href="http://www.bbc.com/news/magazine-35786771">uploading personalities</a> into a digital environment. Here worlds can be tailored to suit individual or collective taste without environmental impact. </p>
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<img alt="" src="https://images.theconversation.com/files/139213/original/image-20160926-31862-7iavo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/139213/original/image-20160926-31862-7iavo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=821&fit=crop&dpr=1 600w, https://images.theconversation.com/files/139213/original/image-20160926-31862-7iavo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=821&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/139213/original/image-20160926-31862-7iavo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=821&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/139213/original/image-20160926-31862-7iavo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1032&fit=crop&dpr=1 754w, https://images.theconversation.com/files/139213/original/image-20160926-31862-7iavo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1032&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/139213/original/image-20160926-31862-7iavo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1032&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">Tsiolkovsky imagined that the free energy of the sun would meet all human requirements for warmth and sustenance.</span>
<span class="attribution"><span class="source">Russian Academy of Science</span></span>
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<p>In the 1890s, Russian space pioneer <a href="http://www.mapcon.com/konstantin-tsiolkovsky-role-in-rocket-science">Konstantin Tsiolkovsky</a> hypothesised that living in microgravity (when people and objects appear to be weightless) would eliminate social disparities. Basking in the full energy of the sun, with no need for houses or furniture, everyone would be equal. </p>
<p>While this vision has not been realised, digital habitats seem to offer similar potential. The trappings of status in the “real” world, with all their attendant costs, need only be imagined to come into being; a new body or an elaborate castle are just a matter of coding.</p>
<p>But our experience with cyberspace to date suggests that class, race and gender <a href="http://culturalpolitics.net/digital_cultures/global">still structure access to resources</a>. The impacts of colonialism have contributed to a “<a href="https://en.wikipedia.org/wiki/Digital_divide">digital divide</a>” that mirrors the old geopolitical frontiers.</p>
<p>Virtual communities can also be places where the worst of human behaviour is nurtured. Some argue that this is because people don’t yet perceive the online environment as “real”. Hence they think the social consequences of their aggression cannot be real. </p>
<p>How, then, do we define reality when human interactions and material culture become numbers stored in machines?</p>
<p>It may be that the ultimate frontiers of the future will be boundaries between different levels of engagement with the material world. The “haves” may withdraw into quantum computers, rather than colonising other planets, and leave the “have-nots” to tackle the global unpredictability of the <a href="http://www.ibtimes.com/what-anthropocene-epoch-humans-climate-change-have-brought-new-geological-era-experts-2408732">Anthropocene</a> era.</p>
<h2>A thirst for the new</h2>
<p>If crossing frontiers consistently fails to deliver utopia and instead replicates terrestrial inequalities, is there any cause for optimism?</p>
<p>People on Earth avidly follow the discovery of <a href="https://theconversation.com/explainer-how-do-you-find-exoplanets-24153">expolanets</a> (a planet that orbits a star outside our solar system). Witness the frenzy that accompanied the announcement of the <a href="http://news.sky.com/story/new-planet-found-which-humans-could-colonise-10550245">potentially-habitable Proxima b</a> in August. </p>
<p>The live exploration of inaccessible ocean landscapes through remote cameras, like those of the <a href="http://www.noaa.gov/">US National Oceanic and Atmospheric Administration’s</a> research vessel <a href="http://oceanexplorer.noaa.gov/okeanos/explorations/explorations.html">Okeanos Explorer</a>, is equally compelling.</p>
<p>Humans, it seems, have a thirst for escape. We hope that elsewhere – wherever that is – things may be better. </p>
<p>But this particular version of elsewhere has proved to be elusive. In the end, frontiers are not crisp lines on maps, but complex historical processes. As legendary explorer <a href="https://en.wikipedia.org/wiki/Freya_Stark">Freya Stark</a> (1893-1993) said, “every frontier is doomed to produce an opposition beyond it”. </p>
<p>This, then, is our mission: to reconcile the opposites on the near side, before boldly going further into the beyond.</p><img src="https://counter.theconversation.com/content/65568/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alice Gorman is a member of the Space Industry Association of Australia and the Australian Institute of Aboriginal and Torres Strait Islander Studies.</span></em></p>Technology had enabled humans to explore the deep sea, the Earth’s poles, and outer space. But we shouldn’t forget historical lessons about frontiers in the process of traversing them.Alice Gorman, Senior Lecturer in archaeology and space studies, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/184392013-09-19T21:46:01Z2013-09-19T21:46:01ZProof of alien life? You need a lot more evidence than that<figure><img src="https://images.theconversation.com/files/31667/original/h26msxzt-1379626011.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Funny looking alien.</span> <span class="attribution"><span class="source">University of Sheffield</span></span></figcaption></figure><p>Could life really exist on other planets? The most positive scientific answer we can offer is: well, maybe, but we do not yet have enough evidence for or against.</p>
<p>Yet Milton Wainwright and colleagues from the Universities of Sheffield & Buckingham would seem to disagree with that. They seem to have found evidence of life-forms in Earth’s atmosphere, delivered from space. The press has rapidly and <a href="http://www.independent.co.uk/news/science/the-truth-is-out-there-british-scientists-claim-to-have-found-proof-of-alien-life-8826690.html">uncritically echoed these claims</a>.</p>
<p>This most definitely grabbed my interest. There has been a lot of talk that life on earth was seeded from space, a hypothesis called panspermia. It has been considered for hundreds of years, and has got a boost from modern research: life, in the form of bacterial colonies, can survive under the extreme conditions found within space environments. But is there physical evidence for “life arriving from space”? Such evidence would be monumental.</p>
<p>On reading results from Wainwright in the <a href="http://journalofcosmology.com/JOC22/milton_diatom.pdf">Journal of Cosmology</a>, I would suggest the jury go back to deliberate some more. What the authors report sending a balloon for obtaining tiny objects from the lower stratosphere, which they examined using a scanning electron microscopy.</p>
<p>They found something called a “diatom frustule”, which is, in essence, the non-living outer shell of a dead organism, a type of algae that thrives in rivers, streams and oceans. Diatoms are so common and so populous in such environments that they are central to those ecosystems. Wainwright makes a case that the inanimate material they see once belonged to a living entity.</p>
<p>The elephant in the room of course is, how did the diatoms end up in the stratosphere?</p>
<p>The authors conclude that they come from some other planet. But the explanations and (more to the point) the scientific evidence provided in the authors’ paper are rather weak. While terrestrial sources for diatoms so high in the stratosphere, such as volcanic eruptions & contamination of the original sampling equipment are considered unviable by the authors, they offer as an alternative that the material must have come from space. However, to date there is no supporting evidence for that hypothesis either.</p>
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<a href="https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=525&fit=crop&dpr=1 600w, https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=525&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=525&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=660&fit=crop&dpr=1 754w, https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=660&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/31669/original/byqr63nr-1379626722.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=660&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Diatom frustule.</span>
<span class="attribution"><span class="source">University of Sheffield</span></span>
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<p>As a sceptical scientist, I would argue that Wainwright has found evidence for some inorganic particle (a composite of silicon and oxygen) in the lower stratosphere. It looks from the morphology (for we have no more to go on than that from the paper) as though it may have been the mineral shell of a living organism, a diatom. An organism found more than 20km up in the sky—how did that get there?</p>
<p>One could propose that it could have come from place A (somewhere down below, from the Earth) or it could have come from place B (somewhere up above, from outer space). What do we know about places A and B? We know that place A is teeming with diatoms and other exotic forms of biological life. We know also, at this point in time, that place B has no life that we can definitively say originates there. So, on balance, a sceptical scientist might focus their attention more on place A.</p>
<p>Doing so means being able to eliminate all suggestion of terrestrial contamination or mechanism for organisms or their remains being delivered to the stratosphere. Both of these hypotheses have a <a href="http://arstechnica.com/science/2013/09/explosive-dispersal-microbes-hitch-a-ride-on-volcanic-eruptions/">greater probability</a> of being answered to the satisfaction of the scientific community than one based on life from space.</p>
<p>As someone who was turned on to science by the wonder of life on other worlds, I am genuinely excited by that possibility. But, as a trained scientist, that excitement will only be realised through scientifically justified evidence. As we stand now, I remain to be swayed by the scientific weight of argument in favour of life from space.</p>
<p>As for the press that has uncritically spread these claims, I can only suggest further developing its sense of scientific skepticism. A good start might be to compare the general reliability of the <a href="http://journalofcosmology.com">Journal of Cosmology</a> to that of more mainstream scientific journals.</p><img src="https://counter.theconversation.com/content/18439/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Kee has received funding from the EPSRC and STFC and currently receives funding from the Leverhulme Trust and the EC through the Marie Curie Programme. He is President of the Astrobiological Society of Britain.</span></em></p>Could life really exist on other planets? The most positive scientific answer we can offer is: well, maybe, but we do not yet have enough evidence for or against. Yet Milton Wainwright and colleagues from…Terry Kee, Reader, University of LeedsLicensed as Creative Commons – attribution, no derivatives.