Many would say the Moon makes a lot more sense as the first place to send humans. Right now, in the ISS, then they can't even wash their own clothes, but send all their dirty clothes to be burnt up in the atmosphere and replaced from Earth. They need to be supplied by many tons of provisions every year. They have medical issues with zero g flight, and nobody has yet spent two years in space in zero g. They haven't yet got a closed system for oxygen, and rely on tons of water supplied each year to break into hydrogen and oxygen to breath, and the CO2 discarded to space. They have made a few experiments in growing plants in space, but nowhere near supplying even a tiny fraction of their own food.
And - they have lifeboat spaceships attached to the ISS which can return to Earth within a few hours if any emergency situation develops - with fully worked out plans of what to do in that eventuality. It's not just a token measure. Mainly for orbital debris impact - but a Mars mission could easily have an Apollo 13 moment - if something went wrong with the life support, they are over six months journey, could be over 2 years journey back to Earth in worst case - that's for Mars orbit.
Surely we need to show that we can support a mission of two or more years closer to Earth first, for instance, on the Moon?
Yes some of the technology might be different but there are lots of parallels.
But as well as that - on the Moon then they aren't interfering with scientific investigations, or not so much. On Mars, you would need to be very sure that the astronauts won't bring Earth life to the planet - or else, any life you find on the planet, your first assumption would be, that it comes from Earth. We mustn't let that happen. If we do go to Mars then it is much safer, scientifically, to go to Mars orbit or to its moons Deimos or Phobos and to explore Mars from orbit via telepresence. It would be an exciting mission and Mars looks almost Earth like from orbit. From the ground, it would be not much different from the Moon but with a muddy brownish red landscape rather than a dark gray one. From orbit, you could explore it with enhanced vision.
The radiation protection isn't that great on Mars by the way. It is protected somewhat from cosmic radiation - same levels as the ISS - which is sufficiently high that they have to watch their exposure levels like nuclear plant workers. But it's hardly protected at all from the slower moving particles of solar storms, because it has no magnetic field. They would be deadly to any astronaut caught out in them without protection. So most of the time it is similar to living in the ISS but during solar storms, then the ISS is protected but Mars surface is not.
Safest place in terms of solar storms and cosmic radiation is in caves. There are probably many lunar caves. In terms of cosmic radiation they may be the best place. Or just pile lots of regolith on top of your settlement. I expect astronauts on the Moon, if they spend long periods there, like years, would spend much of their time in their shelter anyway controlling robots remotely. After all any EVA is dangerous, potentially risking your life. With the ISS then the eventual plan is to reduce the amount of EVAs and do more of it robotically. In the not so distant future, some suggest, EVAs may almost stop altogether. Except maybe for recreation, like the nearly as dangerous cave diving. You don't realise how dangerous it is because it is done by experts who take many precautions and have to follow protocols very carefully to keep it safe. For the likes of you and me, if not trained, it would be very dangerous indeed.
Whether we do it eventually I don't know. Some have said that if we find interesting non terrestrial life on Mars we should leave it to the Martians. But at any rate, I don't think it will happen as quickly as the optimists suggest, especially the Elon Musk and Mars One ideas that you can just bundle a bunch of volunteers out to Mars, with near future technology and that they'd be able to build a colony. Imagine doing that, but you send them to Antarctica, or to the summit of Mount Everest, or to the middle of the Gobi desert - these places are far far more habitable than Mars. Apart from anything else, you can breath the air (On Mars you are in a near vacuum and the moisture lining your lungs would boil even supplied with oxygen, so you have to have a full spacesuit just as for the ISS EVAs) and don't have to try to make all your air from ice or by recycling with plants. And you don't have to wear spacesuits to repair your habitats. Or build them to hold in ten tons per square meter of atmosphere.
When they say Mars is easier than the Moon - perhaps in some ways, in other ways the Moon may be easier - no dust storms for instance, and 24/7 solar power if you went to the peaks of eternal light. But these are very tiny advantages of one or the other compared to the huge difference between either and Earth. So given that, many would say, the Moon is obviously the place to go first because it is so close to Earth. If anything goes wrong you can be resupplied within a couple of days - or in worst case, get back to Earth within a couple of days. You could have "lifeboat spaceships" just as for the ISS all fueled up and ready to return the entire crew to Earth within two days, if any emergency happens. And colonization is hardly a very likely thing to happen in the near term, in either of these places. More likely temporary settlement such as we have already in the far more habitable Antarctica.
As for the idea that Mars is more like Earth because it could be terraformed - if you've read the Mars trilogy and think it could be terraformed in two or three centuries - that's science fiction. In reality nobody knows if it can be terraformed, or is sure how to do it. The Mars Society, who are likely to be optimistic, estimate a thousand years to reach the point where trees can grow on Mars, then a few more thousand years to be able to breathe oxygen. Others would say a hundred thousand years to generate enough oxygen for humans to breathe. But we don't know if it has enough materials to terraform it, you might need to import a planet's worth of nitrogen (for a buffer gas) and water, and even CO2 from comets. All we know for sure is that it has enough CO2 to double its atmospheric pressure, to 2% of Earth's - and if we did that, it would lose that CO2 back to its poles quickly because with its current distance from sun and orbital tilt, then a 2% atmosphere is unstable.
But even if we could somehow transport the Earth atmosphere and ecosystems to Mars, they wouldn't survive. It's far too cold. To keep it warm enough for trees you need greenhouse gases. Just CO2 is not enough. Or orbiting thin film mirrors with total area the size of a planet. For all future time. And if it can indeed be terraformed as quickly as a thousand years, it could "unterraform" probably as quickly. In any case will lose its water in the long term.
Whether it can ever be terraformed, who knows? Whether we will want a terraformed Mars a thousand years from now, again who knows? But in any case we are surely not yet anywhere near the stage where we can take on a thousand year terraforming project with uncertain outcome. Abandoning it half finished would be like leaving a baby child floating in the sea and hoping it would survive. And with Mars so different from Earth there are many things to go wrong. Present day Mars may well be the end state of an early Mars which had life on it. It doesn't follow at all that adding life to a planet will make it more habitable. Perhaps sometimes it does, sometimes it doesn't. I think in any case we don't know enough.
But whether or not, again the most modest of the terraforming projects involves building several hundred full scale half gigawatt nuclear power stations on Mars and mining many cubic kilometers of fluorite ore to use to make greenhouse gases. Can you imagine building a nuclear power station on Mars using spacesuits? What could we do on Earth or the Moon with that level of technology?
Whether we ever do this sort of thing eventually during the next few thousand years - in the near term it certainly doesn't make Mars more habitable than Earth and won't help at all with survival for the first people to land on the Moon or Mars. It doesn't make it any safer or more habitable in the near term, that, theoretically, if everything worked out, if you accept the optimistic views of the Mars society, building lots of greenhouse gas factories, it just might be possible to get to the point where you can grow trees a thousand years from now. Given that right now it is far less habitable than Antarctica.
For that matter, theoretically you can terraform the Moon also. It requires constant input of comet material to maintain its atmosphere. And there are many "gotchas" and things that could go wrong. But it could in theory be done. Does that make the Moon a better place for humans to build habitats in the near term, that you could theoretically terraform it? Or paraterraform it?
See also Trouble With Terraforming Mars
And - they have lifeboat spaceships attached to the ISS which can return to Earth within a few hours if any emergency situation develops - with fully worked out plans of what to do in that eventuality. It's not just a token measure. Mainly for orbital debris impact - but a Mars mission could easily have an Apollo 13 moment - if something went wrong with the life support, they are over six months journey, could be over 2 years journey back to Earth in worst case - that's for Mars orbit.
Surely we need to show that we can support a mission of two or more years closer to Earth first, for instance, on the Moon?
Yes some of the technology might be different but there are lots of parallels.
But as well as that - on the Moon then they aren't interfering with scientific investigations, or not so much. On Mars, you would need to be very sure that the astronauts won't bring Earth life to the planet - or else, any life you find on the planet, your first assumption would be, that it comes from Earth. We mustn't let that happen. If we do go to Mars then it is much safer, scientifically, to go to Mars orbit or to its moons Deimos or Phobos and to explore Mars from orbit via telepresence. It would be an exciting mission and Mars looks almost Earth like from orbit. From the ground, it would be not much different from the Moon but with a muddy brownish red landscape rather than a dark gray one. From orbit, you could explore it with enhanced vision.
The radiation protection isn't that great on Mars by the way. It is protected somewhat from cosmic radiation - same levels as the ISS - which is sufficiently high that they have to watch their exposure levels like nuclear plant workers. But it's hardly protected at all from the slower moving particles of solar storms, because it has no magnetic field. They would be deadly to any astronaut caught out in them without protection. So most of the time it is similar to living in the ISS but during solar storms, then the ISS is protected but Mars surface is not.
Safest place in terms of solar storms and cosmic radiation is in caves. There are probably many lunar caves. In terms of cosmic radiation they may be the best place. Or just pile lots of regolith on top of your settlement. I expect astronauts on the Moon, if they spend long periods there, like years, would spend much of their time in their shelter anyway controlling robots remotely. After all any EVA is dangerous, potentially risking your life. With the ISS then the eventual plan is to reduce the amount of EVAs and do more of it robotically. In the not so distant future, some suggest, EVAs may almost stop altogether. Except maybe for recreation, like the nearly as dangerous cave diving. You don't realise how dangerous it is because it is done by experts who take many precautions and have to follow protocols very carefully to keep it safe. For the likes of you and me, if not trained, it would be very dangerous indeed.
Whether we do it eventually I don't know. Some have said that if we find interesting non terrestrial life on Mars we should leave it to the Martians. But at any rate, I don't think it will happen as quickly as the optimists suggest, especially the Elon Musk and Mars One ideas that you can just bundle a bunch of volunteers out to Mars, with near future technology and that they'd be able to build a colony. Imagine doing that, but you send them to Antarctica, or to the summit of Mount Everest, or to the middle of the Gobi desert - these places are far far more habitable than Mars. Apart from anything else, you can breath the air (On Mars you are in a near vacuum and the moisture lining your lungs would boil even supplied with oxygen, so you have to have a full spacesuit just as for the ISS EVAs) and don't have to try to make all your air from ice or by recycling with plants. And you don't have to wear spacesuits to repair your habitats. Or build them to hold in ten tons per square meter of atmosphere.
When they say Mars is easier than the Moon - perhaps in some ways, in other ways the Moon may be easier - no dust storms for instance, and 24/7 solar power if you went to the peaks of eternal light. But these are very tiny advantages of one or the other compared to the huge difference between either and Earth. So given that, many would say, the Moon is obviously the place to go first because it is so close to Earth. If anything goes wrong you can be resupplied within a couple of days - or in worst case, get back to Earth within a couple of days. You could have "lifeboat spaceships" just as for the ISS all fueled up and ready to return the entire crew to Earth within two days, if any emergency happens. And colonization is hardly a very likely thing to happen in the near term, in either of these places. More likely temporary settlement such as we have already in the far more habitable Antarctica.
As for the idea that Mars is more like Earth because it could be terraformed - if you've read the Mars trilogy and think it could be terraformed in two or three centuries - that's science fiction. In reality nobody knows if it can be terraformed, or is sure how to do it. The Mars Society, who are likely to be optimistic, estimate a thousand years to reach the point where trees can grow on Mars, then a few more thousand years to be able to breathe oxygen. Others would say a hundred thousand years to generate enough oxygen for humans to breathe. But we don't know if it has enough materials to terraform it, you might need to import a planet's worth of nitrogen (for a buffer gas) and water, and even CO2 from comets. All we know for sure is that it has enough CO2 to double its atmospheric pressure, to 2% of Earth's - and if we did that, it would lose that CO2 back to its poles quickly because with its current distance from sun and orbital tilt, then a 2% atmosphere is unstable.
But even if we could somehow transport the Earth atmosphere and ecosystems to Mars, they wouldn't survive. It's far too cold. To keep it warm enough for trees you need greenhouse gases. Just CO2 is not enough. Or orbiting thin film mirrors with total area the size of a planet. For all future time. And if it can indeed be terraformed as quickly as a thousand years, it could "unterraform" probably as quickly. In any case will lose its water in the long term.
Whether it can ever be terraformed, who knows? Whether we will want a terraformed Mars a thousand years from now, again who knows? But in any case we are surely not yet anywhere near the stage where we can take on a thousand year terraforming project with uncertain outcome. Abandoning it half finished would be like leaving a baby child floating in the sea and hoping it would survive. And with Mars so different from Earth there are many things to go wrong. Present day Mars may well be the end state of an early Mars which had life on it. It doesn't follow at all that adding life to a planet will make it more habitable. Perhaps sometimes it does, sometimes it doesn't. I think in any case we don't know enough.
But whether or not, again the most modest of the terraforming projects involves building several hundred full scale half gigawatt nuclear power stations on Mars and mining many cubic kilometers of fluorite ore to use to make greenhouse gases. Can you imagine building a nuclear power station on Mars using spacesuits? What could we do on Earth or the Moon with that level of technology?
Whether we ever do this sort of thing eventually during the next few thousand years - in the near term it certainly doesn't make Mars more habitable than Earth and won't help at all with survival for the first people to land on the Moon or Mars. It doesn't make it any safer or more habitable in the near term, that, theoretically, if everything worked out, if you accept the optimistic views of the Mars society, building lots of greenhouse gas factories, it just might be possible to get to the point where you can grow trees a thousand years from now. Given that right now it is far less habitable than Antarctica.
For that matter, theoretically you can terraform the Moon also. It requires constant input of comet material to maintain its atmosphere. And there are many "gotchas" and things that could go wrong. But it could in theory be done. Does that make the Moon a better place for humans to build habitats in the near term, that you could theoretically terraform it? Or paraterraform it?
See also Trouble With Terraforming Mars
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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