{"id":30,"date":"2007-03-15T10:04:42","date_gmt":"2007-03-15T15:04:42","guid":{"rendered":"http:\/\/www.starshipnivan.com\/blog\/?p=30"},"modified":"2015-06-13T09:23:44","modified_gmt":"2015-06-13T13:23:44","slug":"making-aliens-3","status":"publish","type":"post","link":"https:\/\/starshipnivan.com\/blog\/?p=30","title":{"rendered":"Making Aliens 3: The Landing"},"content":{"rendered":"

\"europa.jpg\"The Repercussions of Planetary Settlement<\/strong><\/p>\n

by Athena Andreadis<\/p>\n

Art image: Europa<\/em>, by Joe Bergeron<\/p>\n

Part 3: The Landing<\/strong><\/p>\n

Even if we come up with propulsion systems that shrink the distances between the stars, they are just the overture to a very long and difficult opera. If our venture out is not to be merely a more expensive repetition of our vanity foray to the Moon, we have to give serious thought to how we will live on extraterrestrial planets.<\/p>\n

Like good representatives of humanity, we will address this question through technology — but the vital question is, which technology. We have three choices:<\/p>\n

1. closed systems — terrariums for people such as Biosphere 2;
\n2. terraforming — making other planets Earth-like; and
\n3. genetic engineering — changing ourselves and our imports to suit our planet host.<\/p>\n

Science fiction, especially in its film incarnations (with its preference for filiming in California), has spoiled us by postulating a universe that is excessively endowed with Earth-like planets. Even when shuttles are forced to perform unscheduled emergency landings, they invariably crash on planets where neither breathing apparatuses nor protective clothing are necessary, and which often tempt the crew with hanging fruit and dancing girls. But how likely is the existence of all the Xerox copies of Earth that have been paraded throughout sf films and series, from Star Trek to Star Wars?<\/p>\n

At this point, evidence is steadily accumulating that Jovian planets are circling other suns. Where big gaseous planets exist, small rocky ones also must lurk. Nevertheless, all the planets that belong to the same class as Earth will differ widely in their outcomes, just as tiny details in our local drawing boards have generated environments as different as Earth and Venus, and on Earth itself hot springs and frozen mountains, and lifeforms as diverse as roses and sea urchins.<\/p>\n

The final state of a planet depends on a huge number of variables — type of primary, distance from primary, system configuration, planetary mass, rotation rate, inclination of orbit, number and size of moons, thickness and composition of atmosphere. So, contrary to the optimism of science fiction, we’re unlikely to ever find a twin Earth. If we find planets within another star’s habitable zone, we will probably need to either terraform them extensively or genetically engineer the colonists so that they can survive without external aid — for example, make them able to hibernate. But let’s suppose that we do find an unspoiled second Earth. Even if it fulfills all the requirements of the long astrophysical \/ planetological list, details are also important<\/p>\n

For instance, one issue rarely discussed in science fiction is that all molecules involved in life display the property of chirality (Greek for “hand”). That is, they are fundamentally asymmetric. Life on Earth has exclusively chosen one of the two possible configurations — the “left-handed” orientation — and has stuck to it throughout its evolution.<\/p>\n

If the biochemistry of New Earth is right-handed, we won’t be able to digest any native foodstuffs, because our digestive apparatus will not be able to degrade them into useful units nor use them for energy. No matter how luscious the fruit appears, it will be strictly eye candy. The alternative will be to introduce terrestrial animals and plants, which may overwhelm indigenous life.<\/p>\n

Other problems could doom would-be colonizers. Gravity significantly lower than terrestrial will make our muscles atrophy and turn our hip and leg bones brittle. More crucially, gravity seems to play a role in embryo formation and in correct configuration of brain synapses. It will avail us little to go to another planet, if we cannot have children, propagate plants — or think straight. Even subtle shifts will lead to problems: for example, we have an in-built circadian rhythm of about 24 hours. If you think jet lag is bad, imagine what it would be like to suffer from it permanently, living on a planet whose length of day differs greatly from that of Earth. Just as a day of different length will confound our biological rhythms, a primary star of a different color will do the same to our vision (as explored by Ursula LeGuin in her short story, The Eye Altering<\/em>).<\/p>\n

Such dislocations would drastically decrease our ability to survive, because the compatibility of inner and outer cues intimately affects competence and health. Too, recent results from orbital experiments show that mice born in low gravity have a permanently different sense of balance and of 3-D space and, unlike adults transiently exposed to low gravity, they don’t re-adjust their brain wiring upon return to Earth. Contemporary Westerners tend to forget that even Earth presented humans with major survival challenges before engineering and medicine relegated most of them to dusty museum dioramas.<\/p>\n

Even if we find an ideal planet, should we try to colonize it, given the dismal record of human colonization on Earth? An Earth-like planet could harbor intelligent indigenous life, though some scientists believe that self-aware intelligence might be very rare in the universe. They point out that humanity is the only species that became sentient on Earth, even though billions of other species have existed during the planet’s 4.6 billion year history.<\/p>\n

I think that is too pessimistic an assessment. The fact that humans stand alone does not preclude non-human sentience, on Earth or elsewhere. Once humans developed intelligence they cut off the possible evolution to sentience of any other terrestrial species, even of close humanoid cousins who were already making the transition to high intelligence. The dice of evolution never fall the same way twice. If events had occurred just slightly differently on Earth, humans wouldn’t have appeared. For example, the impact of the large meteor on the Yucat\u00e1n Peninsula 65 million years ago, which wiped out the dinosaurs, gave mammals their big chance.<\/p>\n

Though humans are unique in the cosmos, intelligence most likely is not. If a planet is Earth-like enough to tempt us to settle on it, I think it will be favorable enough to eventually grow its own version of intelligence. This raises a serious ethical dilemma, and past human behavior is not reassuring on this point. Paradoxically, this is why we need to send the ships out early, before Earth runs out of resources. If we send out expeditions at the last possible moment, when our very survival is at stake, we won’t have the luxury of factoring ethics into our equations and we’ll undoubtedly swarm over the new planets like army ants, denuding and devastating as we go.<\/p>\n

Making Aliens 1: Why Go at All?<\/><\/p>\n

Making Aliens 2: The Journey<\/a><\/p>\n

Making Aliens 3: The Landing<\/p>\n

Making Aliens 4: Playing God I<\/a><\/p>\n

Making Aliens 5: Playing God II<\/a><\/p>\n

Making Aliens 6: The Descendants<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

The Repercussions of Planetary Settlement by Athena Andreadis Art image: Europa, by Joe Bergeron Part 3: The Landing Even if we come up with propulsion systems that shrink the distances between the stars, they are just the overture to a very long and difficult opera. If our venture out is not to be merely a […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6,10,5],"tags":[],"class_list":["post-30","post","type-post","status-publish","format-standard","hentry","category-biology-and-culture","category-science","category-space-exploration"],"_links":{"self":[{"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/30","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=30"}],"version-history":[{"count":0,"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/30\/revisions"}],"wp:attachment":[{"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=30"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=30"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starshipnivan.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=30"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}