No Escape From Problems in Space Colonies - Earth is Des Res - Even After Nuclear War or Asteroid Impact
    By Robert Walker | April 15th 2014 07:57 PM | 13 comments | Print | E-mail | Track Comments

    Most of us don't give much thought to the idea of escaping our problems on Earth by going into space. But those who want to colonize Mars often see it as an urgent need for humanity, to have a potential "second home" as they see it. It's also a common theme of science fiction, for instance in "If I forget thee, Oh Earth" by Arthur C. Clarke. In this case his young protagonist is on the Moon, looking towards the Earth.

    It was beautiful, and it called to his heart across the abyss of space. There in that shining crescent were all the wonders that he had never known—the hues of sunset skies, the moaning of the sea on pebbled shores, the patter of falling rain, the unhurried benison of snow. These and a thousand others should have been his rightful heritage, but he knew them only from the books and ancient records, and the thought filled him with the anguish of exile.

    Why could they not return? It seemed so peaceful beneath those lines of marching cloud. Then Marvin, his eyes no longer blinded by the glare, saw that the portion of the disk that should have been in darkness was gleaming faintly with an evil phosphorescence: and he remembered. He was looking upon the funeral pyre of a world—upon the radioactive aftermath of Armageddon. Across a quarter of a million miles of space, the glow of dying atoms was still visible, a perennial reminder of the ruinous past. It would be centuries yet before that deadly glow died from the rocks and life could return again to fill that silent, empty world.
    Image to the right is the front cover of the first edition of "Expedition to Earth" which has this as one of its stories.

    Asimov has a similar idea in his stories - the surface of Earth gradually becomes more and more radioactive in an irreversible process over thousands of years, and eventually humanity has to leave. You can find many stories on a similar vein.

    Now, there's no doubt that Earth will become uninhabitable eventually, short of some vast megatechnology (e.g. able to move planets around in the solar system). Roughly a billion years from now the sun will get hotter, as it slowly transitions to its red giant phase - and the seas will boil. Over a long period of time, it will lose all its atmosphere and water and become a dry rocky planet and then will get so hot, the surface rocks will melt. It may get swallowed up by the expanding sun, or it may survive, but for sure the oceans and atmosphere won't survive. See Future of the Earth (wikipedia).

    Artist's impression by Fsgregs of a far future Earth after the sun goes red giant. It has lost its oceans and atmosphere long ago. Earth might possibly escape total destruction from the sun however.

     If there are any intelligent creatures like us on Earth with space faring capabilities in those times, they will surely leave Earth in their spaceships long before that happens. They might well migrate to Mars which might, in the natural course of events, briefly become habitable as the sun warms up, and be an oasis on the way to Jupiter. Or they might live in free floating settlements made from material from the asteroids and comets, able to survive anywhere in the solar system. 

    They probably won't resemble us - after all a billion years ago the trilobites probably hadn't evolved yet, indeed it's before the mysterious Ediacaran lifeforms.

    The mysterious fractal form of Charnia. Though it looks like a plant or seaweed, it can't be a plant, as it lived at levels of the oceans too deep for photosynthesis. Nobody really knows what it is and how it lived, though it's believed it fed off nutrients in the water. The fossil was found by a school boy Roger Mason, in 1957 - and was actually spotted a year earlier by a 15 year old school girl Tina Negus who told her geography teacher about it - but she simply said it was impossible and didn't bother to follow up her report. You can read her story in her own words here: " An account of the discovery of Charnia"

    When the Earth becomes uninhabitable and loses its oceans a billion years from now, our descendants, or descendants of other creatures on Earth, will be at least as far removed from us in time as we are removed from Charnia.

    Our descendants would have to leave Earth - but not any time soon.

    So for sure we do have to leave Earth - but many have a sense of urgency about this - that we should set up a colony on Mars as soon as possible, even if it turns out that this will make it far harder or impossible to find out in detail what Mars is like in its present biologically reasonably pristine state.

    So, could we make Earth uninhabitable? Could we make it so uninhabitable that our descendants need to leave the Earth and migrate into space in the near future, as in the science fiction stories by Arthur C. Clarke, Asimov, and others?

    Nuclear test in Bikini Atoll in 1954

    Well there is no doubt that a nuclear war would cause many problems on the Earth, especially with the nuclear winter. 

    The Kuwaiti oil fires in the Gulf war. The thick smoke caused a drop of temperature of the region by several degrees C - but as Carl Sagan wrote, "as events transpired, it was pitch black at noon and temperatures dropped 4-6 C over the Persian Gulf, but not much smoke reached stratospheric altitudes and Asia was spared."

    A nuclear winter could cause conditions like that for several years over the entire world. 

    Then there are various other things, for instance, new diseases that could wipe out humanity.

    There are astronomical events also which could cause problems. A giant impact for instance, like the one that brought an end to the dinosaur era. 

    Artists' impressions of giant impacts on the Earth. Some of these might cause a firestorm over the entire Earth, which burns up just about everything and makes most species extinct over the entire Earth.

    That sounds pretty dire. But, the first thing to bear in mind is that these events are rare, only every few tens of millions of years for the largest ones. We can expect many smaller meteorites, before one of these monsters, in ordinary course of events.

    Yes, this is going to happen eventually - if we don't find a way to deflect them first. But - "eventually" here means, most likely a few million years from now.

    Meanwhile our main priority probably should be tracking the rather smaller city threatening meteorites, which may hit every few centuries. Once we can deal with those, any really large threats should also be easy to spot. We may be able to deflect those also, and at any rate in the not so distant future, with the entire solar system carefully mapped out, right out to the Oort cloud surely if we remain a technological civilization, we will have plenty of warning to decide what to do about them.

    Even after a global firestorm, and most species extinct, then the Earth would still have its atmosphere and its oceans. It would be far more habitable than Mars or the Moon. If you were in either of those places, then your best chance of surviving is to get back to Earth, if you can make it here. Because here, you won't need to create your own oxygen, water is abundant, you have protection from cosmic radiation, have normal atmospheric pressure. Any humans left on Earth would have a far better chance of surviving than, say, Mars One or SpaceX colonists on Mars with no support from Earth.

    Even after a nuclear war, there would be uninhabitable places on the Earth for sure, but we don't have the technology to make the entire surface of the Earth radioactive. 

    We can't even make Earth as hazardous to health as the cosmic radiation that bathes the entire surface of Mars. On Mars humans need meters of soil to protect them from cosmic radiation because they don't have the protective atmosphere of the Earth. On Earth even after a nuclear war, you wouldn't need that much protection except at the worst hot spots of radioactivity.

    If you can somehow survive the event itself (say underground or beneath the sea) then the Earth would remain a far more benign place to live than anywhere else. And it's far easier to go underground or under the sea for survival than to travel to Mars or the Moon to do that. 

    If you want to terraform anywhere in the solar system after such an event, then again we are already in the right place. The Earth is the only place that is worth working on, to get a habitable planet again in the shortest possible period of time.

    Indeed Earth will become reasonably habitable within a few years even after a global firestorm just by itself, so long as some plants survive at least in seed form. If the fires are so extensive that no plant seeds survive on the Earth itself, then so long as some survive in deep seedbanks like the Svalbard Global Seed Vault in Norway (entrance shown in photo to the right, it's a deep passively cooled seed bank), whatever humans remain on Earth could use these to restore the Earth.

    Early science fiction writers had the idea that a nuclear chain reaction could become a runaway reaction in ordinary materials in the Earth's crust and indeed make the whole surface radioactive. Asimov took that idea and with the aid of a bit of sci. fi. technobabble created an almost believable future scenario where it happens as an unstoppable thousands of years long process. But we don't have any way of doing such a thing in reality.

    Other cosmic events similarly can't make Earth as uninhabitable as Mars, or at least, the chance is so tiny as to be almost infinitesimal. To take the main examples.

    1. A nearby supernova. We know all the nearby stars able to go supernova in the next few million years, and none are near enough to cause serious problems to the extent of making the whole Earth uninhabitable. 
    2. A gamma ray burst. This could make half of Earth uninhabitable - but the other half would survive, as it is of such short duration, with the main effect over in seconds, or minutes at the most. 
    3. A black hole. Well this could destroy the Earth. But in practise - though theoretically you could have primordial black holes able to do this - it doesn't seem that there are any, or at least not many, not enough to be an event to worry about. Because the sun still survives. Conceivably there could be an embryo planet that got lost into a black hole, in the early solar system, and we might not notice it. But the sun is a far larger target than any planet. If there were trillions of mini black holes roaming our galaxy, the stars would blink out, and our sun is far more likely to get hit than any planet. There may well be huge black holes, there may even be micro black holes created in the early universe, but they can't be numerous enough to be a big issue for us.
    4. Impact by an embryo planet or giant comet. These were common in the early solar system. But not likely now. If there were frequent giant comets visiting the inner solar system, we'd see the impact scars on the Mars and the Moon. They do have huge scars, but the really big ones all date back to the first few hundred million years of our solar system. There is one possibility though. Mercury might hit the Earth. But no need to lose any sleep over this. If it happens (itself a low probability event), it will be a billion years from now - gradually perturbed by resonances with Jupiter - and most likely to hit Venus or escape the solar system - but might hit the Earth. If that happens our future descendants may need to worry about it - but not us, not for a few hundred million years at least.

    We think we have problems here on the Earth but compared to other places in the solar system, really, we have things easy here.

    Mars colonist enthusiasts talk about technological methods which they believe could solve all the problems of Mars. The problem with this as a motivation for colonizing Mars is that the same technology would let you colonize inhospitable areas of the Earth for a far lower cost than Mars. 

    And on Earth, much of it is not even needed, especially the technology to generate oxygen from ice, or to create buildings able to hold in ten tons per square meter of outwards atmospheric pressure in the near vacuum of Mars, or the technology to protect buildings from cosmic radiation, or the technology for space suits to let you go outside your habitats.

    So it doesn't make too much sense to use these expensive technologies to colonize Mars if you are looking for somewhere to live. Far better to do something like the seawater greenhouse or other technologies for reversing desertification on Earth.


    As for escape to space to avoid violent tendencies of humans on Earth - we can only really hope to survive in space if we can learn to be somewhat more peaceful than we are now, not just in space, but on the Earth also. 

    If you took present day technology and put it back in a time machine to the early twentieth century, I think it's reasonably clear that humans then wouldn't be able to handle it. Without all the understanding and safeguards we developed over the last century, then they might well go extinct in some great war, using biological weapons, jet fighters, nerve gas, and other chemical weapons, atom bombs and so forth.

    Similarly if the ordinary person today had the ability to go into space as easily as we can fly in an airplane, including for instance all the countries on the Earth, even the most unstable ones - I'm not sure if we'd survive that level of technology right now. Space settlements would be particularly vulnerable. So - if we do colonize in space, we need to be sure that we do that in a peaceful way, or our attempts will probably not last long, with the fragile colonies and spaceships vulnerable to impacts with tiny pieces of debris travelling at the speeds of interplanetary spaceships. Surely if we are afraid of consequences of our violence on ourselves on Earth - then it's not really the best time to go into space, as similar violence with highly developed space technology would be far worse.

    If we attempt to escape into space we will just take all our problems with us, and they would loom far larger in the fragile and difficult conditions of space colonies.

    We have made a great beginning here with the Outer Space Treaty with its emphasis on cooperation and peaceful development of space, and with no country able to claim territories in space. I think we need to build on that - but much as one might like to rush into space and develop quickly - perhaps we are better off learning to walk before we run.


    To trash Earth enough so that an escape to Mars makes sense we'd have to somehow get rid of all the water - including all the oceans - all the oxygen of course, and nearly all the atmosphere leaving a laboratory vacuum - all the ice also except a fifth of the ice in Antarctica (spread over the surface of Earth would be about equivalent to the ice on Mars) -and  get rid of the Earth's magnetic field which protects us from solar storms and also protects water vapour in the upper atmosphere which otherwise would get split and lost.

    Then - reduce the amount of sunlight to a half (that by itself is enough to plunge Earth into a snowball phase) - greatly increase meteorite impact rate (because Mars is so close to the asteroid belt) - reduce the gravity to a third (we don't know if this low g is healthy for humans and it means also that you need e.g. three times as much oxygen and nitrogen for the same atmospheric pressure) - and stop continental drift (which on Earth is what returns the CO2 to the atmosphere long term).

    You might think that a global firestorm could reduce the amount of oxygen in the Earth's atmosphere, because we rely on plants to create it. But it turns out, we have enough oxygen in the atmosphere already to last us for millennia. Though there are fluctuations every year, due to seasonal effects of plants growing and dying, without this life the oxygen would remain in the atmosphere for thousands of years and just slowly get absorbed in the oceans. Plants and sea algae would grow back within a few years, certainly in centuries, plenty of time to replenish the oxygen again after a firestorm.

    And - those who talk about terraforming Mars may not realize that the most optimistic projections make it a thousand year process. This is how the Mars society imagines it - and they are the most optimistic of all about terraforming (outside of science fiction of course):

    When have we ever done a highly technological project that takes a thousand years to reach completion? We have difficulty keeping on track with a technological space project for 20 or 30 years. And those are the projections of the Mars society optimists. 

    Others think that it would take far longer, at least to have any chance to breath the atmosphere. Chris McKay estimates 100,000 years to a breathable atmosphere - and with many things to go wrong along the way. 

    The reason for this difference of opinion here is that the oxygen needs to be separated from carbon dioxide, carbonates or water - most likely from carbon dioxide if there is enough of it. To do that using life processes, you need plants to not just grow, but to capture meters thick layers of peat, or other organics over the entire surface of Mars. The carbon you extract from the CO2 has to go somewhere.  And you have to counter natural process of decay that recapture the oxygen created as CO2 and return it to the atmosphere, and other processes involving life forms consuming the oxygen as soon as it is created. If you just look at creation of oxygen and ignore its consumption, the situation looks much more optimistic, but realistically, you can't do that without huge megatechnology, e.g. perhaps global greenhouses or some such. At least nowhere on Earth do you get carbon capture fast enough to create an oxygen atmosphere in less than many millennia, and with the reduced light levels on Mars, and the need to create three times as much oxygen for the same atmospheric pressure in the lower gravity of Mars, that becomes Chris McKay's 100,000 years.

    We seem to find it impossible on Earth, with all our billions and our vast industry - to adjust the CO2 levels of the Earth's atmosphere back down by 0.01% of the Earth's atmospheric pressure from 400 parts per million back to the pre-industrial 300 parts per million. 

    If we can't do that, how can anyone suppose a small colony on Mars could keep its atmosphere stable when it starts to go in unexpected directions? Or in the other direction, if we had technology that permitted terraforming Mars then we could stop global warming pretty much overnight.

    It just doesn't bear close scrutiny I think. Working through ideas for terraforming Mars I think is of great benefit so long as you keep it to the ideas stage. It's great for clarity of thinking, better understanding of processes of Earth, and understanding how we can re-terraform areas of Earth that become desert like.

    But when it comes to actually terraforming other planets, I think we are talking about centuries into the future. That is, unless there is some huge fast increase of understanding and knowledge. 

    It's probably like interstellar flight. We have many ideas for interstellar flight. Some are actually practical right now. If we desperately needed to do an interstellar flight we could do it with a generational spaceship and using hydrogen bombs to fuel it as in the Orion project design. 

    Project Orion - this nuclear powered spaceship would weigh thousands of tons, powered by hydrogen bombs. We could build it now (though it would of course violate the nuclear test treaty). A large enough version, using many times the total existing arsenal of nuclear weapons on the Earth could actually travel to nearby stars.

    But if we do want to go to other stars, there is no point in setting out right now assuming our technology continues to advance, as spaceships launched a few centuries from now would surely easily overtake these slow interstellar giant ships.

    But any spaceship we launch right now would take centuries and most likely thousands of yeas to get there. So long as we continue as a space faring civilization, then future interstellar spaceships would easily overtake the ones launched in the early centuries of a space civilization. As time goes on, through advancing technology, the expected arrival dates of an interestellar spaceship at nearby stars will get earlier and earlier, and for as long as this process continues,it doesn't make much sense to set out on the voyage, except as a desperate last ditch attempt (more about this in the comments to this article).

    It's the same with any mega-engineering projects expected to take thousands of years to reach completion. It actually is likely to help to start later - because if you start too soon, then you are likely to do things that will mess it up and make it harder for later engineers.

    For instance, Mars has reasonable quantities of dry ice, and water ice at present. This may be useful in the future - but if we were to warm it up now, and things go wrong, it might well combine to make carbonates or in other ways become unavailable to future terraforming attempts. And as already said, any life we introduced can't be removed as far as we know and makes irreversible changes to the planet - which our successors may not welcome.

    So, until we know what we are doing, the chances are that we could make other planets worse, especially if you introduce life forms to another planet. That's a big irreversible unknown, what living things would do to future terraforming attempts, if done without understanding the consequences. Introduce species that would fight against the things you wish to achieve and it could set back the process by centuries, or make it impossible.

    For that reason, as well as to protect Mars for future scientific study until we know what's there, I think humans with their trillions of microbes in thousands of species should not go anywhere near Mars surface though they could be of great benefit in close to Mars orbit exploring via telepresence, e.g. able to drive a successor to Curiosity tens or even hundreds of kilometers every day and look for life in real time via telepresence.

    The rovers are our eyes, and boots, and hands on other worlds at present and I think we need to continue that way - at least for a while yet.

    Artist's impression of ExoMars - ESA rover which they plan to send to Mars in 2018 - the first rover since Viking able to search for life directly on Mars. It is able to detect life in the heart of the Atacama desert (which Curiosity couldn't do and only the labelled release experiment on Viking could do - for more on that see Rhythms From Martian Sands - What Did Our Viking Landers Find in 1976? Astonishingly, We Don't Know)

    The main focus of ExoMars is on past life, and it is not going to visit the places most habitable for present day life - but does have the capability of spotting present day life as well if it comes across it.

    Our current rovers are slow, only able to travel less than 100 meters a day - but future rovers will be able to travel kilometers per day. They will be able to explore a pristine Mars (hopefully anyway if the planetary protection measures to date have worked) because we haven't yet contaminated it with Earth life and haven't yet colonized it. 

    Later, then we may be able to send humans to Mars orbit to control a wide variety of rovers on the surface in real time, including rovers able to fly, and explore caves and the Valles Marineres and other exciting - and dangerous - places on Mars. As the technology develops we will be able to control mechanical humanoid avatars also - and in that way put "telerobotic" boots on Mars.

    Let's keep Mars pristine, at least for a while, so that we can explore it in its original state!

    If we find interestingly different life on Mars we may need to keep it free of Earth life indefinitely. If so that should be a cause of celebration as it means Mars is a really interesting place to study and explore, though best done via telepresence at least with present day technology.

    We don't need to be depressed at this. But rather, excited. We live in amazing times, with the solar system still relatively pristine, so we can actually look at the planets and see what they were like originally. On Mars, we have the opportunity to study a planet that may well have evolved life independently, quite possibly in a different direction from Earth - or if it evolved similarly to Earth - hasn't had all the traces of the early stages of evolution erased by continental drift. Like Earth, it had oceans and ideal conditions for life in the early solar system. Unlike Earth - much of it surface has remained pretty much unchanged, in a deep freeze, since the very beginnings of the solar system.

    If we use these times to just spread the pollution of Earth life to as many places as we can in the solar system, as the colonists wish to do, our future descendants may well look back at our times with regret, and wish they lived now, in times when the solar system was still in such a pristine state, and wonder what knowledge they lost. 

    I would apply this even to the Moon. Rather than look at the ice at the lunar poles and just think about how best we can use it to spread humans through the solar system - let's instead consider what a wonderful opportunity we have to study these still pristine deposits which may have information about the very early solar system. I think anything like that should be first studied by scientists - and only used for fuel and other resources once we know for sure what it is that we have there. Perhaps some of these deposits might be valuable in other ways - particular craters or particular deposits of especial interest, but there is no way we can judge this now, either way, with our current so limited knowledge of the solar system.

    I'm not at all saying we won't or shouldn't set up human colonies in space. Just that, for the time being anyway, these are going to be research outposts, like the settlements in Antarctica - probably with few permanent residents. Simply because it doesn't make practical sense to go anywhere outside of Earth as a permanent place to live, or a second home, no more than it makes sense to live in Antarctica permanently - and Mars, the Moon, and the asteroid belt and all other locations in the solar system are far less hospitable than many relatively uninhabited areas of the Earth such as deserts, and polar regions.

    We'll also have industry in space eventually too, surely, do already to some extent with the satellites. We may have humans in space for industrial reasons. But they would be mostly focused on helping the Earth, for instance solar satellites in space to beam power to the Earth, constructed using materials in space. Or building research stations for scientists, and places for tourists to visit. We'll surely have adventurers and explorers exploring the solar system eventually also just as they did in Antarctica. We may have wealthy billionaires who set up permanent homes in space because it's a cool place to live.

    But in the near future at least for some time, unless there is some huge game changing technology, I don't see any scope for a second home for humanity in space. At least, not until we have totally sorted out our problems on Earth first. Then we'd go into space and perhaps find second homes there eventually, but not as an escape from Earth, more as part of a process of discovery and adventure and learning new things.

    This is Princess Elizabeth research station in Antarctica - Belgium's station, and the first "zero emission" research station in Antarctica; it generates all its own power.

    Space colonies, I believe, are likely to start as research stations like this, inhabited mainly by scientists, who are there because they find the solar system utterly fascinating. They will probably have visitors also - tourists, journalists, adventurers and so on, there for shorter periods of time - plus staff who are there to help keep the station running. But for ordinary people, there won't be much of interest to keep you there for months and years on end, and they are certainly not an easy place to set up home in the near future.

    What do you think? If you have other ideas about this, or any other thoughts on any of these points do say in the comments and let's have a vigorous discussion! And any questions also, do ask away.

    There are several articles about this that I wrote here: Let's Plan For Exploration and Discovery of Space with no End Date - NOT Escape from Earth - Opinion Piece - talks in detail about some of the things we might discovery in space and why our solar system is well worth the trouble and expense of exploring, particularly for life discoveries.

    And one that got a lot of attention: Trouble With Terraforming Mars - many details that make Mars so hard to terraform, and some of the many things that could go wrong.

    And you can try some of the other articles in my blog at

    I originally wrote this as a comment to an interesting article on io9 by Annalee Newitz called "The One Scientific Field Most Likely to Get Humanity Into Space" - it's well worth a read if you haven't seen it, takes another interesting perspective on this whole question.


    This article (and the whole of this series) are definitely in the top echelon, and apart from agreement, there’s nothing of significance I can add to the discussion.  However, I hope you don’t mind me indulging in a little flippant humour:—

       Man at door: “So there really is life on Mars!”

       Alien: “No way man!  That’s why we have to come all the way here to party.”

    On The Sky at Night (BBC TV) we learned that the people developing that ESA rover are calling it “Brian”.

    Now there  I detect more than a mere hint of humour.  At present, on British commercial TV and radio, we are being subjected to advertisments from an insurance comparison website, featuring a most annoying robot called “Brian” [1] which goes around pestering potential customers with estimates as to how much they could save on their car insurance.  I feel it’s more than likely that that’s where the ESA folks got the name from!

    [1] nothing to do with the picture, which is a toy from the Japanese manufacturer Masudaya
    Robert H. Olley / Quondam Physics Department / University of Reading / England
    Oh right, I missed that Sky at Night. There are a few days left to watch it for anyone in the UK (not sure if you can watch it outside the UK).  Has a lot about Mars
    The Sky at Night - Mysterious Mars

    Actually seems, Brian is the name for the prototype they use for testing ExoMars navigation in the Mars Yard :).

    Glad you like the article, and thanks for the fun UFO toy image :).
    Very fine article, Robert.

    I'm sorry to say that this article is much better than what I was expecting from the title.  Instead, I was very pleasantly surprised to find this article to be well thought out, and articulately expressed.

    Thank you, for this great article.  I think you have covered this quite well.


    David, thanks, glad you like it. I find the title in some ways the hardest part of writing an article :). Go through many changes before I settle on final version.
    Have noticed though, that e.g. the BBC website does the same - their article titles go through frequent changes during the day after a story breaks.

    Anyway am trying a slightly different title now, "Why There's No Escape From Our Problems On Mars, The Moon, or in Space Colonies if We Trash Earth"

    But may go through other variations also. My "Trouble with Terraforming Mars" title came from another website that used that title to link back to my article, and I liked it so much used it for the original article, don't think I'd have thought of that title by myself.

    It makes a surprising difference, for instance, sometimes just by changing the title on an article it moves several places up in the panel to right here, and the time visitors spend on the article increases as well, I think because the article matches what they expected when they clicked on the link - if it's a good article, but not what they expected or were interested to read about, many visitors will click away quickly.

    Anyway glad you like the article, Thanks!
    You speak of not starting on mega-engineering projects, because discoveries of faster methods made during the process would possibly be made harder to use. And yet, you give no suggestion of WHAT time frame it would be appropriate to start the process? You bring to mind a story by Alan Nourse, called "The Martyr" (available on Project Gutenberg), where life extension becomes real, and as a result the mega-engineering project to build a starship becomes lost in a swarm of changes made to make things better, more perfect, over and over, because the leaders of the project now feel they have the time to do it RIGHT.

    Ultimately, we'll never learn the real problems associated with terraforming until we either have perfect knowledge, or we actually try it. Witness the recent issue with a leak in the spacesuit on the ISS - it was actually something that was impossible here on Earth, because we don't have freefall here on Earth to any real degree, so no amount of testing found it, or would have found it.

    Certainly, we should do a lot more testing and research before we even attempt it (though I would be curious about tossing a few Falcon 9 loads of extremophile organisms into the clouds of Venus to see what happens...), but the fact that we cannot perfectly predict what will happen should not be seen as a blocking issue.

    Honestly, from the title, I thought you were going to speak on the basic physics issue of the impossibility (barring huge teleportation fields people could just walk or ride through) of evacuating all humans from the planet. Especially with current rockets, but even with the Space Elevator (few do the math to realize just how long a ride on the Space Elevator would be from Earth to GeoSynch! I expect cargo will ride it all the way up, but humans will likely end up riding a rocket-car that gets dropped from the cable at some point over the majority of the atmosphere.)

    Oh sorry, need to work on the title some more. The title you saw was a new one I did just a few minutes before your comment. That's an interesting topic too but not what I wanted to talk about here.


    Actually I don't think that it is at all impossible for all the humans on Earth, or as many as want to, to migrate into space in the future if technology develops a bit more, and there was any point in it.

    Right now of course is impossible. But in not so distant future it may be as easy to fly into space as to fly to another country, with technology such as the British Skylon fly directly to orbit with a single engine, no rocket stages, or the JP Aerospace idea to fly airships to orbit - or improved re-usability of the rocket stages with more conventional methods with Space X's ideas. 

    If so - well we have about a billion airplane flights a year on Earth. So if it gets as easy to fly into space as to go to somewhere else on the Earth - then we could fly the entire population of the Earth into space in just a few years. 


    But - this was the point of the article - there isn't any point in doing that if you are looking for somewhere to live, because nowhere in space is as worth terraforming as the Earth.

    Really - only if you have reversed all the problems we've already caused on the Earth - and also terraformed all the deserts - and then if you are still looking for places for people to live (if our population expands further) - start building colonies over the seas of the Earth as well, probably floating or below the sea colonies - all that is far easier and more productive than any space colony ideas could be.

    Only when the Earth is completely colonized with humans - then it would be worth terraforming places in space. 

    Or some game changing technology. For instance 3D printers at nanoscale plus self replicating machines - those could transform space development of course, e.g. self replicating solar panels in space, almost unlimited energy - and building entire habitats in space automatically using the replicators. Then - would be easy to colonize space. But of course that would also completely transform life on Earth as well. It's  probably not much point trying to work out what we'd do in that situation, it would probably be different from anything we can expect right now.

    Meanwhile, of course can go into space for adventure, fun, tourism, etc. Am not saying anything about that at all.

    It's just the idea that we could solve the problems we have on Earth by starting up a new colony in space that doesn't have those problems that this article is about. Anywhere in space would have far greater problems than we have on Earth, as a place to live, and even after terraforming, same is true, for centuries into the future.

    And if we can colonize space as easily as we can on Earth - then that means we have already got the resources and technology to solve all our current problems on EArth - of course probably created many more as well, but e.g. surely global warming and shortage of resources would no longer be an issue in such a world.


    Well - so long as it is a thousand year project - at the most optimistic and most likely a 100,000 year long project - I think we do need to just wait for new technology to develop. It's just too long a timescale to contemplate. And - given that the problems we have are right now, and need to be solved in decades, these terraforming ideas aren't going to solve those. 

    So, if you attempt to terraform some planet - you are doing it, clearly, for our descendants a thousand years from now, and not for us now. But how do we know what our descendants a thousand years from now would want us to do to the solar system?

    If you don't see it as something that has to be done urgently to solve our present problems - well you don't have to do it at all right now. Give time to find out more about Mars, explore it, and decide what it is we should best do in the future.

    With a thousand year long project - well the delays have to be seriously long, like many centuries, to have a significant impact on how long it will take. Especially if there are mistakes we could make that would make it take ten times longer or be impossible, and things we might be able to do that would half the time or even a tenth of the time, who knows, with ideas we don't even know about yet.

    We can surely delay starting on it by at least a century - which would surely also lead to new ideas and avoid mistakes that would save much more than a century on such a project.

    And also, on that timescale, well we could create habitats from materials in the asteroid belt also - and that gives the possibility of living area far larger than Mars, land area of a thousand Earths, see my article 

    Asteroid Resources Could Create Space Habs For Trillions; Land Area Of A Thousand Earths

    So, perhaps we don't need to be so focused on colonizing and terraforming planetary surfaces. When you have a habitat in space, then you can make it Earth like in decades, even less, depending on its size. Something like the Stanford torus - they planned to complete it within 40 years. We could now do that more quickly surely.

    That is - if we can solve the closed habitat issues. If we can make a closed self contained habitat in space - with all the biological cycles working - that's a major challenge that's within our ability to try to tackle, like terraforming in its scope but far more manageable by humans. And if we make a mistake - well in the worst case, say some biological disaster, diseases that become more potent in the space environment, viruses, or whatever, things not expected - I expect biology, because of its complexity to give us the most unpredictable and tricky surprises if we try to set up entire working small scale ecosystems in space - well in worst case you evacuate the atmosphere, sterilize the soil, and start again.

    You can never do that with a planet.

    Then if you can do that - then you can create also much larger habitats - even world sized habitats in space - lots of smaller ones or big ones with the entire surface of the Earth in a single habitat. Again that's a massive engineering project - but probably an easier project than terraforming Mars - I think personally anyway - to create a habitat or habitats in space with surface area as large as Mars. And one that isn't irreversibly contaminating a planet that might have such extra-ordinary insights into the past of our solar system and evolution.


    With interstellar flight - well surely we'd send unmanned probes before humans in that case, light things just a few kilograms, perhaps solar sails. So we are a bit away from that.

    You have to deal with that paradox somehow - if we do send a mission now, then you can be pretty sure it's going to be overtaken before it is anywhere near to its destination, probably when it is only a fraction of a light year from Earth. Same is also true of interstellar robotic probes so long as they are slow.

    So - well to break through that, you'd need a mission that's going to get to the nearest stars in decades rather than centuries. Which may be possible with lightweight robotic pioneer ships in the not too distant future. As with exploring the solar system I think robots first.

    As we do the robot missions, we can look at what is happening to the time to get to nearest star, and draw a graph and work out, when you think the best time is to set off on an interstellar flight.  Obviously if the time it will take on the flight is going down faster than time is progressing on the Earth then it would be silly to set off - unless as a last ditch attempt before some disaster about to destroy civilization.

    But at some point then the time it will take on the flight will stop going down quite so quickly - and your estimated time of arrival will start moving forward in time rather than backwards. At that point you could think about setting off, if you really want to do it. Same for robotic missions to other stars. You have to think a bit also about - might there be some big game changing technology leap. But if it gets down to decades to get to the stars, you might as well set off anyway.


    At that point, though, if sending humans, I think would need to give some serious thought about - should we explore the galaxy or colonize it? I've covered this a bit in my Why Didn't ETs, Or Self Replicating Machines, Colonize Our Solar System Millions Of Years Ago?

    The thing is - as Steven Hawkins has talked about how we should perhaps not advertise our presence in case there are ETs with not so benign intentions. Well actually - I think that's unlikely to happen that way, myself, because it would be such a surprising coincidence if they have just evolved at same time as us. If they've been around for billions of years - well they have obviously left Earth alone, so can't be on a major campaign to try to colonize all the real estate in the galaxy. If they wanted Earth - well they could have had it millions of years ago before humans evolved here.

    But it's a different matter if we set off waves of  colonizing humans into the galaxy ourselves. Who knows what they might evolve into. Just because they are our distant great great great grand children thousands of generations removed - doesn't guarantee that by the time they get back to us a few millennia from now, that they will treat us well and have good intentions towards us. 

    And - they could also be well intentioned - but unwise. Just needs one high tech but stupid colonist to make self replicating Von Neumann machines at some point down the road that could, literally, trash the galaxy, e.g. the paperclip event horizon idea., someone makes an unstoppable paperclip making machine - with ability to improve its own programming and machinery - and it turns all the galaxy into paperclips - not because it has any ulterior motive, but just because that's what it was programmed to do - and becomes unstoppable because of recursive self improving algorithms.

    So, I think we need to give a lot of careful thought before colonizing the galaxy - is that really what we should do? It might be that all sensible ETs come across this very issue and decide it's not wise, and limit themselves to exploring the galaxy only rather than colonizing  - and never settling anywhere except their home planet - or maybe some limited number of planets, set a limit, say 4, or 128 or whatever, and stop at that point.

    I wish the answer was otherwise. But so far nobody has come up with a satisfactory answer to that. Well - David Brin has the idea of a whole ecosystem of different replicators so they keep each other in check - might be that's the situation already - but I rather hope not, as that's quite a bleak and dangerous universe to live in. At any rate, if the galaxy is not like that - and I htink reasonable chance it isn't as no obvious large scale changes to it, especially, no sign of any self replicator machines transforming our own solar system - then we need to be careful not to set it in that direction.


    With Venus - well - there is less there to damage with Earth life probably - at least the surface of Venus - but still - there just possibly might be life already in the Venus atmosphere. See my If there is Life in Venus Cloud Tops - Do we Need to Protect Earth - or Venus - Could Returned XNA mean Goodbye DNA for Instance?

    And - there are ideas for terraforming Venus -and ideas for cloud colonies - but I think there also we should study first. It's not like a petri dish that we can just throw stuff at it, see what happens - and if it goes in some way we don't like - try again with another planet. Need to give some thought to what's the effect longer term down the road. 

    E.g. one simple question to think about. If there are cloud colonies in Venus - and I think it is the most terraformable planet actually in that respect - what happens to all those billions of people if later on we decide we need to do something more drastic - like remove most of Venus's atmosphere or some big mega-engineering project or other involving impacts of comets on Venus or whatever?

    And - would any life introduced be beneficial to the colonists? And might others be harmful to them - it might matter what kinds of micro-organisms we introduce first, in what order we introduce them to the atmosphere.

    - and if there is life there already - definitely need to keep it pristine for now I think, and find out what it is - that would be amazing. The problem is - if you introduce Earth life - especially the archaea - they can do this amazing thing of gene transfer using GTA agents. This lets the archaea transfer fragments of DNA to completely different species, even different phyla - almost totally unrelated - except of course in very distant past, same origin of DNA and cell machinery.
    So the DNA would get scrambled up if the DNA on Venus is compatible with Earth DNA. And if not - is possibility of out competing it - as an XNA for whatever is native there - same as for Mars. I talk a bit about that in the article.

    So - yes might be our first terraforming experiment, to introduce life to the Venus atmosphere. Certainly less ramifications than introducing it to Mars - at least you'd think - but still - may not be ramification free. It may need some careful thought and planning. And surely shouldn't do that blind without studying it first.
    Trying a new title, maybe give a better idea of what the article is about, at least doesn't suggest is a problem with actually physically getting humans away from Earth, "No Escape From Our Problems in Space Colonies - Des. Res. of Solar System is Earth"
    Sorry no idea what a "Des. Res." is.

    British informal A desirable residence (used as a humorous allusion to the language used in housing advertisements): they are converting a Victorian schoolhouse into a des res

    Robert H. Olley / Quondam Physics Department / University of Reading / England
    Thanks, yes that's it exactly :). Didn't realize it was a British thing.
    There are a few reasons like religion and politics for which, conceivably, to operate without interference would outweigh the disadvantages of colonization. The threats of violence remain, in that case, possibly even exacerbated. But in general humanity is short sighted and opportunistic: the technology to colonize these environments is relatively close. It may be an act of faith on your part, Robert, to try to speak reason instead of to try and delay the advance of technology!

    What's more, while there may be more cosmic radiation on mars, the danger of nuclear war isn't external radiation, which your article seems to be comparing directly, but contamination with chemically indistinguishable isotopes which are much more dangerous inside the body. I shouldn't guess what degree cosmic radiation induces radiation in surface isotopes on mars.



    Peter, first on the danger of cosmic radiation on Mars - the main risk there is from cancer as I understand. It depends how much you are exposed. But the thing is - that on Mars, same also in space and on the Moon - that it's currently impossible to protect someone in a spacesuit from cosmic radiation. You can be protected in a shelter with meters of cosmic radiation shielding (it is far more penetrating than normal radiation).
    Here is what I say about it in Why Mars is NOT a Great Place to Live - Amazing to Explore From Orbit - with RC Rovers, and Nature Inspired Avatars

    "The NASA career limit for astronauts is based on a 3% risk of cancer in your lifetime. They also estimated that any astronauts who die of cosmic radiation induced cancer have their life expectancy reduced by 15 years approximately (this depends on your age, and whether you are a man or a woman, and the margins of error are large).

    If you follow those guidelines, adults over 30 could spend an average of two hours a day in spacesuits, if they are willing to take a 3% chance of a fifteen year life expectancy reduction. This would include time spent in vehicles roving over the surface as these can't be shielded with meters thick layers of regolith. It would also include time spent in greenhouses on the surface if illuminated with natural light - because the amount of air in a greenhouse wouldn't give any protection from cosmic radiation. Basically humans would need to be pretty much troglodytes, living under several meters of soil for most of their life, on Mars.

    That is unless you deflect the sunlight into the greenhouses with giant mirrors - that's how they get around the issue with the space habitats such as the Stanford Torus - mirrors that reflect light in an angled path around into the habitat, but cosmic radiation just flies straight through the mirrors and is blocked by the shielding, so can't get around the angles into the habitat.

    Cosmic radiation damage, credit NASA
    This shows cosmic radiation damage of DNA. On the surface of Mars every cell will get hit many times by highly energetic cosmic rays, which on Earth are absorbed by our thick atmosphere and the magnetosphere. Mars has no thick atmosphere and almost no magnetic field.
    Most colonists would spend as much time indoors as possible. If you limit yourself to a couple of hours out of doors (including in vehicles) a day, that leaves you with a 3% extra risk of a cancer, as best as we can estimate it at present. Of those who die from cancer, on average their life expectancy will be reduced by 15 years (these figures have large error margins).

    Fetus's are especially vulnerable to radiation, based on data from Hiroshima (it's a different type of radiation but the best data we have) then effects could include for instance, severe mental retardation, so it wouldn't be safe for pregnant women to go outside a shielded habitat at all. Babies and young children would also be especially vulnerable.

    Most colonists would surely spend nearly all their time inside the habitats for safety reasons. You would only go out if you had to."

    That's a very different situation from the situation on the Earth after a nuclear war. You'd be able to go out of doors, safely, at least in protective garments, even immediately afterwards, if you keep away from hot spots. As you say, the danger is mainly from ingesting the radioactive materials and not directly from the radiation, which isn't nearly as strong and penetrating as cosmic radiation. And most of the radioisotopes are short lived, so after some months the danger is greatly reduced. The long lived ones are hazardous but not so much as sometimes believed. And eventually you have the hope to clean up the hot spots and return Earth to normal conditions. That would be a far shorter process than any attempt to terraform Mars, not thousands of years, but decades.

    Of course I'm not saying a nuclear war is likely. The world seems far safer in that respect than it was when I was a child in the middle of the cold war. Yet - there are issues of course and can't say it's not going to happen, many nuclear weapons in the world still. 

    But just that - the idea that we should start up a colony on Mars in order to have a second home just in case we have a nuclear war here on Earth - I think is reasonably clear that after a nuclear war, your colonists on Mars would have a far better chance of surviving if they can get back to Earth. Even radiation levels would be less here than on Mars, at least in some places on the Earth - no war can make the whole surface so radioactive it's as dangerous to health as cosmic radiation is on Mars, so long as you take precautions such as taking care about what you eat and filtering the air you breath.

    And to compare like with like - any colonists on Mars would grow all their food in enclosed greenhouses. If you do that on Earth there's no risk of contamination from radioactive materials even immediately after a nuclear war so long as you take care to filter the air and make sure the soil is not radioactive.

    It's not identical in all respects of course, it's a different kind of radiation, more penetrating and danger is directly from damage from the radiation rather than from ingesting materials, but I think reasonable to say that the Martian surface is as hazardous in terms of radiation as the surface of the Earth would be after a global nuclear war.


    Yes of course, people could have all sorts of reasons for going there. Even just, someone who is a billionaire who thinks it is cool to live on Mars and can afford to do it.

    But - we do have precedent here - we are not totally short sighted but a mixture of long and short sighted. That's where the thing I said about putting modern technology into the early C20 say just before WWI comes in. If we had our present day technology back then - the outcome surely would have been uttterly horrific and might even have made us extinct. But given enough time and learning from things that go wrong as technology develops, we can sort those things out at least to some degree.

    So we have the various agreements on chemical and biological weapons, the nuclear test ban treaty, ban on nuclear weapons in space, the various regulations to protect wildlife from DDT, and the ozone layer, agreements to protect Antarctica, quarantine rules to protect vulnerable environments and so on. 

    And - we do have people break those laws also. But still - we do have those laws and they do work enough to make a pretty huge difference.

    Then also - Mars is not really of any great economic value in the near term. It's pretty much like Antarctica in that respect. So - we have the Antarctic treaty which protects Antarctica - and it's probably easier to enforce because Antarctica is so inhospitable. Well that's exactly the situation with Mars, it's far more inhospitable than Antarctica actually, and no obvious source of wealth on the planet of Mars that's worth spending billions to go there to achieve. Just this idea that many people have that it's a worthwhile place to colonize. If you can show that it's not worth colonizing - seems - there really isn't much else to motivate people to go to Mars, at least no more so than the reasons that lead people to go to Antarctica.

    And - you have the outer space treaty. Anyone landing on Mars would need to prove that their expedition will not contaminate Mars in a way that would harm the experiments of other parties to the treaty. And any contamination they cause is the responsibility of whatever country they are a citizen of. So the upshot of that is, that for instance if Mars One sends a mission to the Mars surface and they contaminate Mars, no matter where they launch from in the world, because they are a Dutch company, then the Dutch government will be held responsible for whatever harm they cause on Mars. And other nations also have a say in this too. So - though they seem up beat about all this and say they will keep to all the COSPAR requirements to keep Mars contamination free - I don't see how you can if you land humans on Mars. This would at least have to be proved.

    At least for now, while it's pretty hard to launch to space, and only from countries that are signatories to the OST, then it's reasonably containable. We don't need to convince all the billionaires in the world that they shouldn't colonize Mars. Just need to make sure that the governments keep to the OST, and then they are responsible for preventing their citizens from doing such things.

    It's not reached that point yet, but some time down the line, if Space X or Mars One do get to the point where a mission of humans to the Mars surface seems possible, they will need to get their launch approved by COSPAR, big international conference of thousands of scientists from countries world wide. And all the tendencies of their deliberations so far have been towards stricter restrictions on planetary exploration contamination for the last few years. I'm pretty sure, when the time comes, that they would not be able to approve a mission to the Mars surface - especially since a hard landing by a human occupied ship on Mars - a crash - would immediately cause a huge breach of the OST, irreversible contamination of Mars, almost certainly. And there surely would be crashes, it's an extremely dangerous place to land a spacecraft. It's not for nothing that they called the Curiosity landing "Seven minutes of terror" and Curiosity could very easily have crashed - many previous landers have.

    I think, so long as we can go slowly right now, and not get rushed into it - then people will gradually realise the importance of keeping Mars pristine. Especially if we also start to get interesting new results about evolution from Mars probably everyone will begin to realize the value of a pristine planet. But that will take a while probably, chances are that life may be quite hard to find on Mars, not in the first place you look. So I think so long as we realize that, and you don't get people saying "okay we haven't found life there, how long can we wait, it's probably not got life" - if you realize it's likely to be a long search, at least some more decades, and no actual good reason to colonize it, especially quickly - well I am hopeful that reason will prevail.

    We are capable of reasoning and looking into the future, and for sure, at least, it's not a good reason for contaminating Mars, to say, to paraphrase the argument:

    "Let's contaminate Mars because we've done many stupid and irrational things as a species in the past, so it's just our nature". 

    That's not a good reason for contaminating Mars of course. As humans we can also rise above such things, and have shown many times that we can, as well as failing many times. Let's at least try to be responsible in this area!


    I think you are talking about freedom there. So you have the freedom to colonize - but you also have the freedom to enjoy Mars in its pristine state and to learn the knowledge we can gain about evolution from studying it in its pristine state.

    So - the hopeful colonists - if they contaminate Mars - are infringing on that freedom of everyone else to enjoy Mars in its pristine state - at present as a resource for scientific knowledge of quite possibly inestimable value - could be hugely important to the world to fill in the gaps in our understanding between amino acids and the first primitive cells. One estimate is that there are as many major stages of evolution before the most primitive cells we know about as there were between them and us. And of even greater value if it turns out that life on Mars followed a different path from Earth, even maybe XNA based life.

    They are also infringing on the freedom of anyone who wants to terraform Mars in a more planned out way, say with cyanobacteria for a few decades or even centuries to build up oxygen without aerobes or detritovores to return it to the atmosphere.

    And also infringing on freedom of those who might want to "Marsform" Mars - make it suitable for native Mars life forms - if there is interesting native life on Mars and it is different from Earth life - then such a planet with life with a different basis from Earth life on it, could be of huge interest and value - like an exoplanet in our own solar system but we don't have to travel light years to get to it but can study it close up.

    There may eventually be a big debate about what to do about Mars, if anything - but we don't know enough yet to even discuss that, I think, just that it's clear we shouldn't do anything irreversible to limit our future options such as contaminating Mars with reproducing life forms from Earth.

    So - that's a conflict of freedoms, but you get those frequently, and often have to be resolved by legislation. And the prospective colonists don't have any legal or moral right to make an irreversible decision like that for the rest of us.


    My own hope is that we can find a common ground, rather than a conflict situation, by focusing on telepresence exploration. Use the ideas of the prospective Mars colonists, but in ways that don't irreversibly contaminate Mars. So - you use ideas for generating fuel on Mars - Zubrin's idea - and ideas for thin film solar panels for high levels of electricity for low weight of materials - Mars One idea - but use those to power telerobots on the surface.

    Then you can also use the ideas for habitats - but not on the surface, have them in orbit. If you put them into the HERRO mission's sun precessing Molniya orbit - that's almost a Mars capture orbit, can go into it without aerobraking for less delta v than it takes to get to the Moon. I think it's important not to do aerobraking for spacecraft with humans inside, at current levels of technology, because of increased risk of crashing and contaminating Mars, unless you can show that can't happen - e.g. through some auto pilot / mechanical error.

    They would be pretty much the same as the surface habitats - but removes the dangerous landing on Mars - and for radiation shielding mine materials from the moons eventually - or ship them from Earth / NEOs / the moon or whatever - and for early missions - then it's like a short stay research station, need a fair bit of shielding but people only spend a year or two there at a time then return to Earth. That's perhaps something we could do within a couple of decades or so. Though I think it's not safe right now would be best to do precursors, e.g. to the L2 position far side of the Moon, long mission there simulating the isolation of interplanetary missions - exploring far side of Moon and its poles by telepresence and telerobotic construction of large long wave length radio antenna on the MOon - but within a couple of days to return to Earth if something major goes wrong, Apollo 13 style.

    See TV movies Genesis 2 & Brave New World on DVD.
    One tells about Cryonics & awake 230 years ahead, the other Orbital space city ( 1974 movie debut TV)

    Add a comment

    The content of this field is kept private and will not be shown publicly.
    • Allowed HTML tags: <span> <sup> <sub> <a> <em> <strong> <center> <cite><TH><ul> <ol> <li> <dl> <dt> <dd> <img> <br> <p> <blockquote> <strike> <object> <param> <embed> <del> <pre> <b> <i> <table> <tbody> <div> <tr> <td> <h1> <h2> <h3> <h4> <h5> <h6> <hr> <iframe><u><font>
    • Web page addresses and e-mail addresses turn into links automatically.
    If you register, you will never be bothered to prove you are human again. And you get a real editor toolbar to use instead of this HTML thing that wards off spam bots.