Originally Answered: What would the moon be like if it was terraformed?
It could keep an atmosphere for some time. And mining and just landing on the Moon with rockets would thicken its very thin atmosphere.
Gregory Benford, the hard science fiction writer, thinks so in this rather intriguing article - A Terraformed Moon Would Be an Awful Lot Like Florida
Artist's impression of a terraformed Moon
Terraformed Moon by Exospace on deviantART
There's an interesting site about it, by Nick Hoekzema a scientist from the Max Plank institute: An Atmosphere for the Moon
So rest of this just summarizing what he says:
He works out that you might be able to create an oxygen rich atmosphere by using nuclear weapons, 1% of the US nuclear arsenal would be able to liberate enough oxygen for a thin atmosphere 0.00001% of the Earth's, similar to atmosphere at 100 km height. Which might not seem very useful but he figures out it would stop most micrometeorites as well as block out a lot of cosmic radiation.
But getting it terraformed would involve not just oxygen, which it already has in its rocks and maybe could be liberated - but also lots of water.
Adding all that water, he says, would be a major issue though.
In presence of oxygen all the iron in the lunar rocks would rust (as they have done on Mars) and other elements like calcuim also - and end result would be that it would absorb more oxygen than there is in the Earth's atmosphere before it stabilized.
That would also expand the lunar rocks, he works out, by about 10%. So likely to be Moon quakes as the surface rises, after that expansion down to whatever depth the water penetrates to.
Assuming that's right, and it seems convincing to me, then I doubt if we will terraform the Moon in near future, would be huge effort of mega engineering.
Though in principle see no reason why not if you wanted to, used loads of icy comets, and willing to keep adding more every few millennia.
But may paraterraform it, if you can insulate the surface from the water in some way, i.e. have a "floor" for your world house.
Here paraterraforming means, to cover it in greenhouses - and eventually - they all merge to make a single greenhouse over the entire surface, a "world house".
For the details see An Atmosphere for the Moon
Great image of a terraformed Moon here: The Moon Terraformed LOLA by Ittiz on deviantART (not sure about copyright situation so linking to it rather than embedding)
And of a paraterraformed Phobos gone all the way to a world house, by same artist: Paraterraformed Phobos by Ittiz on deviantART
I can't find a good image of a paraterraformed Moon. But Ittiz's paraterraformed Phobos gives a good idea of what it might be like I think.
See also Robert Walker's answer to Can we terraform the moon? If yes, how difficult is it? Is it possible with the current technology, and what are the major challenges might we face while terraforming?
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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