The main thing is - there is no hurry to get started!
Terraforming Mars, at its fastest, would take a thousand years (Mars society estimate) - and that's without oxygen - followed by several millennia to get an oxygen rich atmosphere (could be 100,000 years according to Chris McKay - and on Earth that took many millions of years) - and that's if it works, with many things to go wrong.
And it needs a long term stable peaceful civilization able to undertake mega-projects with main pay-off millennia into the future - it's a major commitment to take on
It's like having a child. You can't give up when the child is one year old - but are committed to them for the rest of their life. Similarly if we terraform Mars we as a civilization are committed to this - and not just us, but our descendants, through at least several thousand generations into the future.
You shouldn't start on terraforming Mars - and then stop a few decades later - or even a couple of centuries later - because that would be quite likely to leave it in a worse state than when you started.
That's because Mars is not naturally like Earth. Move Earth out to Mars orbit and it would turn into a snowball Earth. Also, Mars has many other differences from Earth - so adding life to Mars certainly won't automatically make it like Earth. It may very well have life already - and if so - that's not made it into an Earth-like planet.
With only a century or so of - relatively - peaceful civilization here on Earth - and when most projects have to be finished within years or decades at most - it's just too soon. We aren't mature enough as a technological civilization to undertake a project that will take several thousand years to complete and one that has to be completed if you start on it.
Then - there are many things to go wrong - such as - that it ends up in a different state from the one you mean to head it into. Again that's a major on-going commitment of mega-technology to keep it on track and to deal with all the crises that would surely arise as various lifeforms take over the planet that are different from the ones you wanted, e.g. eating or interfering with the life you try to seed there.
Plus some out of control life may turn out to be a nuisance for humans also, creating toxic byproducts for us for instance.
So - might well be - that if you wait a couple of centuries before you start - the thing can be done much faster - and you also get a better planet at the end of the thousand year long process.
And - if it really can be terraformed so quickly, within a thousand years then if things go wrong - surely it can be unterraformed as quickly. And we have a long term commitment to future creatures that might evolve on Mars, or our own descendants who may live there, say a hundred thousand years from now.
They are only separated from us by time. But their world might be dying, and they might no longer have the technology to do anything about it, and it's a world we created which - through our ignorance - or perhaps intentionally - has a short time-span before it becomes uninhabitable again.
So you have to think about that also.
And there's a tendency to look at Mars and think - this is the best place for humans to live in the solar system outside of Earth - but - there are enough resources in the asteroid belt to make Stanford Toruses with total surface area a thousand times the land area of the Earth - surprisingly. So - we don't need planets at all - if we want to colonize space. We can also colonize the atmosphere of Venus with floating habitats.
What we can do in the meantime - it is excellent to think about plans for terraforming - can learn a lot from that if you don't actually go ahead and do them - and also can work on closed system habitats - like Biosphere 2. And closed systems and recycling in space conditions.
Those all have no impact on any other planet, as they can be self contained systems in space. So that's where we can make our mistakes - in small habitats - eventually maybe a few square kilometers. But that's where we need to learn, not on a planet - which we have only one of, and where - if we make mistakes - we can never turn back the clock and try again.
See also
Terraforming Mars, at its fastest, would take a thousand years (Mars society estimate) - and that's without oxygen - followed by several millennia to get an oxygen rich atmosphere (could be 100,000 years according to Chris McKay - and on Earth that took many millions of years) - and that's if it works, with many things to go wrong.
And it needs a long term stable peaceful civilization able to undertake mega-projects with main pay-off millennia into the future - it's a major commitment to take on
It's like having a child. You can't give up when the child is one year old - but are committed to them for the rest of their life. Similarly if we terraform Mars we as a civilization are committed to this - and not just us, but our descendants, through at least several thousand generations into the future.
You shouldn't start on terraforming Mars - and then stop a few decades later - or even a couple of centuries later - because that would be quite likely to leave it in a worse state than when you started.
That's because Mars is not naturally like Earth. Move Earth out to Mars orbit and it would turn into a snowball Earth. Also, Mars has many other differences from Earth - so adding life to Mars certainly won't automatically make it like Earth. It may very well have life already - and if so - that's not made it into an Earth-like planet.
With only a century or so of - relatively - peaceful civilization here on Earth - and when most projects have to be finished within years or decades at most - it's just too soon. We aren't mature enough as a technological civilization to undertake a project that will take several thousand years to complete and one that has to be completed if you start on it.
Then - there are many things to go wrong - such as - that it ends up in a different state from the one you mean to head it into. Again that's a major on-going commitment of mega-technology to keep it on track and to deal with all the crises that would surely arise as various lifeforms take over the planet that are different from the ones you wanted, e.g. eating or interfering with the life you try to seed there.
Plus some out of control life may turn out to be a nuisance for humans also, creating toxic byproducts for us for instance.
So - might well be - that if you wait a couple of centuries before you start - the thing can be done much faster - and you also get a better planet at the end of the thousand year long process.
And - if it really can be terraformed so quickly, within a thousand years then if things go wrong - surely it can be unterraformed as quickly. And we have a long term commitment to future creatures that might evolve on Mars, or our own descendants who may live there, say a hundred thousand years from now.
They are only separated from us by time. But their world might be dying, and they might no longer have the technology to do anything about it, and it's a world we created which - through our ignorance - or perhaps intentionally - has a short time-span before it becomes uninhabitable again.
So you have to think about that also.
And there's a tendency to look at Mars and think - this is the best place for humans to live in the solar system outside of Earth - but - there are enough resources in the asteroid belt to make Stanford Toruses with total surface area a thousand times the land area of the Earth - surprisingly. So - we don't need planets at all - if we want to colonize space. We can also colonize the atmosphere of Venus with floating habitats.
What we can do in the meantime - it is excellent to think about plans for terraforming - can learn a lot from that if you don't actually go ahead and do them - and also can work on closed system habitats - like Biosphere 2. And closed systems and recycling in space conditions.
Those all have no impact on any other planet, as they can be self contained systems in space. So that's where we can make our mistakes - in small habitats - eventually maybe a few square kilometers. But that's where we need to learn, not on a planet - which we have only one of, and where - if we make mistakes - we can never turn back the clock and try again.
See also
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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