Moon is far easier because it is closer to Earth. You could do it robotically using telerobots on Mars controlled by operators on the Earth in real time. And far easier to get equipment there - you can do it any time of the year while for Mars you have an opportunity only once every two years for similar amount of delta v. And if you need humans on the spot, can send them from Earth with a few days notice - this is all of course in some future where we have heavy lift and human rated spacecraft able to go to the Moon.
The Moon also has natural caves (so does Mars) - lava tube caves. If we do have humans go back to the Moon and they stay there long term - that's one place they could stay, shielded from cosmic radiation naturally, less building involved.
The alternative is to cover shelters with meters thick layers of regolith.
All this depends on what we find out about the Moon though in preliminary scientific studies. I think it is far too soon to make long term plans as we haven't yet sent even robotic missions back to the surface of the Moon apart from the Chinese mission, and the Apollo missions used old technology - and - they weren't primarily science led. Just the last one had a scientist on board - and with the technology they had then, scientists on the Earth couldn't have a clear view of what was happening on the Moon.
So - though we do have lots of rocks from the Moon - they are from sites selected mainly for safety reasons safe to land on - and the rocks mostly selected by non geologists with some geology field trip training, with limited help from Earth.
So - we know surprisingly little really about the surface of the Moon, especially the most interesting features for humans such as the caves and the ice deposits, you can only see so much from satellites in orbit around the Moon.
So - I think before making any detailed plans we need to study it a lot more first. Lots of robotic missions probably as they are a much lower cost way to find out about it I think especially since they are easily controlled teleroboticalaly from Earth, and driven around in almost real time.
Apart from this, I think that we won't get humans landing on Mars for quite some time for planetary protection reasons - I've written about this in my other answers so won't say much more just now. But that by itself would mean - that we send humans to the Moon first.
There are lots of other reasons that make the Moon the most likely first destination - we don't know yet have any proven capability to keep humans alive as far away as the Moon, without continual resupply from Earth every few months, so it is far too soon to look further afield in my view.
Also, the ISS has a "lifeboat" permanently attached that can be used to evacuate all the crew to Earth within hours. We could do the same on the Moon - in an emergency can be back on Earth within a day or two. But a lifeboat like that would be impossible further from Earth with many months needed to travel back - and could be over two years to get back from Mars depending when the emergency happens. I think it is far too soon to think about deep space missions without a lifeboat capability like that. Never mind one-way missions.
The Moon also has natural caves (so does Mars) - lava tube caves. If we do have humans go back to the Moon and they stay there long term - that's one place they could stay, shielded from cosmic radiation naturally, less building involved.
The alternative is to cover shelters with meters thick layers of regolith.
All this depends on what we find out about the Moon though in preliminary scientific studies. I think it is far too soon to make long term plans as we haven't yet sent even robotic missions back to the surface of the Moon apart from the Chinese mission, and the Apollo missions used old technology - and - they weren't primarily science led. Just the last one had a scientist on board - and with the technology they had then, scientists on the Earth couldn't have a clear view of what was happening on the Moon.
So - though we do have lots of rocks from the Moon - they are from sites selected mainly for safety reasons safe to land on - and the rocks mostly selected by non geologists with some geology field trip training, with limited help from Earth.
So - we know surprisingly little really about the surface of the Moon, especially the most interesting features for humans such as the caves and the ice deposits, you can only see so much from satellites in orbit around the Moon.
So - I think before making any detailed plans we need to study it a lot more first. Lots of robotic missions probably as they are a much lower cost way to find out about it I think especially since they are easily controlled teleroboticalaly from Earth, and driven around in almost real time.
Apart from this, I think that we won't get humans landing on Mars for quite some time for planetary protection reasons - I've written about this in my other answers so won't say much more just now. But that by itself would mean - that we send humans to the Moon first.
There are lots of other reasons that make the Moon the most likely first destination - we don't know yet have any proven capability to keep humans alive as far away as the Moon, without continual resupply from Earth every few months, so it is far too soon to look further afield in my view.
Also, the ISS has a "lifeboat" permanently attached that can be used to evacuate all the crew to Earth within hours. We could do the same on the Moon - in an emergency can be back on Earth within a day or two. But a lifeboat like that would be impossible further from Earth with many months needed to travel back - and could be over two years to get back from Mars depending when the emergency happens. I think it is far too soon to think about deep space missions without a lifeboat capability like that. Never mind one-way missions.
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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