Neither. Both are of great interest for science, and of no interest for colonization at present. The Antarctic treaty means can only be used for pure research, so rules out colonization - at least until time comes for its renewal.
The Outer Space Treaty has no end date, and does not rule out colonization, but makes it clear that any exploration of space has to be done in a way that is not "harmful contamination" which has been interpreted as including, not impacting on the scientific researches of the other member states who signed the treaty.
Anyway- both are rather impractical, though Antarctica less so.
A Mars colonized by millions of humans, with present day technology would need hundreds of thousands of rockets to Mars, every year, to supply them with replacement parts for their spacesuits, environmental units, etc, based on ISS type technology.
And easiest way to feed them, actually, least amount of trips, is to just ship all the food from Earth and not bother with greenhouses on Mars. At least that's what a recent MIT students survey suggested. They were talking about Mars One's plans - but the same is for anything using current technology - didn't assume anything particular to Mars One, just assumed present day technology or near future.
There is no way the Earth economy would support a large settlement like that, not with present day technology. The MIT study found that with present day technology - it goes way beyond our capabilities to launch the 41 rockets needed to be sent every two years once you have 20 people on Mars. That's because they all have to be launched in a small launch window for the Holmann transfer orbit. And that was a lower bound as they didn't take account of everything in their analysis.
And millions of people on a planet, all struggling to survive, all relying on shipments from Earth, won't make the start of a technological base on Mars just by throwing large numbers of people at it. Just more people to die basically if it is as borderline and difficult as it seems would be with present technology.
They are hoping that future technology will solve that, but have no mature technology to base those hopes on yet.
As for terraforming Mars, that's a long distant future hope. And - not at all likely or easy in my view. About 1000 years to get to the point where you have trees and can travel around with aqualung type air breathers without a spacesuit - and that's if it all goes well, but no guarantee it would work out like that, lots to go wrong.
One point I realised just now, listening to a Curiosity talk - one of the experts pointed out that even if Mars had a thick atmosphere like Earth and like it probably had early on - still - the water would all gather at the poles as ice first. So - the amount of ice we have on Mars - well in a thick atmosphere it would need a lot more water just to fill the polar regions with ice. Until that was done the atmosphere would be so dry that the entire rest of the planet would be a desert like the Sahara desert. And that much water - just isn't there as far as we can tell. Nobody knows where it got to - vanished to space through solar wind, or sunk deep below the surface to the hydrosphere kilometers deep? In any case is not available on the surface any more. Yes there is enough ice at the poles to cover entire surface to some depth of water. But not nearly as much ice as there is in Antarctica - and Mars would need a bigger ice cap at both poles than Antarctica I think due to its greater distance from the sun, so colder.
Saying this not to be a "nay sayer" but just practical.
I think also that we shouldn't colonize Mars unless it can be done consistent with planetary protection and at present can't see how that can be possible, because of all the microbes and other lifeforms that we bring with us and would spill out over the surface in case of a hard landing. Likely to end up finding life on Mars and then find out, it is just the life we brought ourselves, and confuses searches for Mars originated life.
But as well as that - it just doesn't seem to be a viable place for a colony if going there just to colonize with no other reason to be there. Far better colonize the deserts of the Earth.
And as for backups- backup on the Earth. No disaster would make Earth so uninhabitable that you won't have at least a few humans survive, e.g. in shelters built to be fireproof and shield from firestorm, or in a submarine under the sea - and those are extreme and extremely unlikely disasters. As for survival due to quarantine because of the distance of Mars from Earth - as travel to Mars gets easier it will no longer be quarantined from Earth n that way - better to set up intentional quarantined islands on the Earth that you need to stay in quarantine for e.g. six months before you visit them - if you think that is a cause for concern.
Go into all this more in my other answers.
See also science20 posts: Trouble With Terraforming Mars and Why We Can't "Backup Earth" On Mars, The Moon, Or Anywhere Else In Our Solar System
And here are some of my Mars answers here on Quora
Mars and Space by Robert Walker on Lists of My Answers
The Outer Space Treaty has no end date, and does not rule out colonization, but makes it clear that any exploration of space has to be done in a way that is not "harmful contamination" which has been interpreted as including, not impacting on the scientific researches of the other member states who signed the treaty.
Anyway- both are rather impractical, though Antarctica less so.
A Mars colonized by millions of humans, with present day technology would need hundreds of thousands of rockets to Mars, every year, to supply them with replacement parts for their spacesuits, environmental units, etc, based on ISS type technology.
And easiest way to feed them, actually, least amount of trips, is to just ship all the food from Earth and not bother with greenhouses on Mars. At least that's what a recent MIT students survey suggested. They were talking about Mars One's plans - but the same is for anything using current technology - didn't assume anything particular to Mars One, just assumed present day technology or near future.
There is no way the Earth economy would support a large settlement like that, not with present day technology. The MIT study found that with present day technology - it goes way beyond our capabilities to launch the 41 rockets needed to be sent every two years once you have 20 people on Mars. That's because they all have to be launched in a small launch window for the Holmann transfer orbit. And that was a lower bound as they didn't take account of everything in their analysis.
And millions of people on a planet, all struggling to survive, all relying on shipments from Earth, won't make the start of a technological base on Mars just by throwing large numbers of people at it. Just more people to die basically if it is as borderline and difficult as it seems would be with present technology.
They are hoping that future technology will solve that, but have no mature technology to base those hopes on yet.
As for terraforming Mars, that's a long distant future hope. And - not at all likely or easy in my view. About 1000 years to get to the point where you have trees and can travel around with aqualung type air breathers without a spacesuit - and that's if it all goes well, but no guarantee it would work out like that, lots to go wrong.
One point I realised just now, listening to a Curiosity talk - one of the experts pointed out that even if Mars had a thick atmosphere like Earth and like it probably had early on - still - the water would all gather at the poles as ice first. So - the amount of ice we have on Mars - well in a thick atmosphere it would need a lot more water just to fill the polar regions with ice. Until that was done the atmosphere would be so dry that the entire rest of the planet would be a desert like the Sahara desert. And that much water - just isn't there as far as we can tell. Nobody knows where it got to - vanished to space through solar wind, or sunk deep below the surface to the hydrosphere kilometers deep? In any case is not available on the surface any more. Yes there is enough ice at the poles to cover entire surface to some depth of water. But not nearly as much ice as there is in Antarctica - and Mars would need a bigger ice cap at both poles than Antarctica I think due to its greater distance from the sun, so colder.
Saying this not to be a "nay sayer" but just practical.
I think also that we shouldn't colonize Mars unless it can be done consistent with planetary protection and at present can't see how that can be possible, because of all the microbes and other lifeforms that we bring with us and would spill out over the surface in case of a hard landing. Likely to end up finding life on Mars and then find out, it is just the life we brought ourselves, and confuses searches for Mars originated life.
But as well as that - it just doesn't seem to be a viable place for a colony if going there just to colonize with no other reason to be there. Far better colonize the deserts of the Earth.
And as for backups- backup on the Earth. No disaster would make Earth so uninhabitable that you won't have at least a few humans survive, e.g. in shelters built to be fireproof and shield from firestorm, or in a submarine under the sea - and those are extreme and extremely unlikely disasters. As for survival due to quarantine because of the distance of Mars from Earth - as travel to Mars gets easier it will no longer be quarantined from Earth n that way - better to set up intentional quarantined islands on the Earth that you need to stay in quarantine for e.g. six months before you visit them - if you think that is a cause for concern.
Go into all this more in my other answers.
See also science20 posts: Trouble With Terraforming Mars and Why We Can't "Backup Earth" On Mars, The Moon, Or Anywhere Else In Our Solar System
And here are some of my Mars answers here on Quora
Mars and Space by Robert Walker on Lists of My Answers
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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