A helluva lot of ice found on Mars

[Admiral Valdemar]

You know, being able to terraform a planet and then form colonies kind've covers the idea of having global positioning systems already. It's like wondering if you're space shuttle will have climate control.

[Molyneux]

But terraforming is a stupid idea anyway. Colossal waste of time and money that will never happen in reality. If we ever have people leave the planet, orbital habitats are superior in every way, both technically and economically.

That's perfectly true...until someone goes stark raving and goes out for a walk with no suit on because they've been living in a tin can for the past decade or so.

I wonder...how much metal would be needed, if one were to try to actually GIVE a planet like Mars a molten metallic core?

[Guardsman Bass]

I think Mars actually is big enough to hold on to at least a breathable atmosphere in the long-term (although it would be thinner than Earth's). You've just got to get that water unfrozen, and enough carbon dioxide to stay in the atmosphere, and hopefully by itself (meaning you don't need humans constantly injecting the gas into the atmosphere).

It's by far the best candidate for terraforming. Venus would be much more of a bitch, in spite of the advantages gained by having a more earth-like planet in terms of size.

[Molyneux]

That's perfectly true...until someone goes stark raving and goes out for a walk with no suit on because they've been living in a tin can for the past decade or so.

You shouldn't comment on something you obviously know nothing about. Read a little about the concept, then get back to me. The picture in my signature is a link to a page with tremendous amounts of information. In short though, it certainly isn't a 'tin can'. An orbital colony (or more accurately, a collection of them) would be more like Earth than a terraformed Mars could ever realistically be, complete with even 1g of gravity, not the 1/3 g you'd have to settle with on Mars. And Earth would be mere days away, not many months away, which has implications all over the place, most importantly IMO are economics, but also inhabitants can take a vacation back to Earth for much less cost than a ride back from Mars. And there is the fact an orbital habitat could be built on the scale of decades at most. Terraforming would take at least centuries.

I wonder...how much metal would be needed, if one were to try to actually GIVE a planet like Mars a molten metallic core?

Metal isn't so much the problem as energy. Mars already has an iron core, and probably used to have a magnetic field and plate tetonics, but it doesn't have sufficient radioactivity in it to keep it warm enough anymore. The amount of energy needed would be very large I'm sure (haven't run the numbers), but I think a bigger problem would be getting the energy down into the core. You are talking about a 2000 mile hole.

Ah...my mistake, I thought that you were talking about, say, a domed or underground colony on Mars or the Moon. Orbital colonies sound good to me, as long as the problem of radiation shielding can be dealt with - and that's by no means insurmountable.

[Admiral Valdemar]

Anm O'Neill Island 3 will have plenty of material on the outside to act as a barrier for all but the most energetic particles. If you can build such structures, shielding shouldn't be a problem with a good dense material like DU or a carbide along with an active EM field.

[loomer]

Well, the sooner we get water miners up there on Mars, the better. Since, you know, the whole fact that there's a fuckton of droughts going on in the World right now. And maybe we could succesfully turn the Gobi desert into farmable land as an exercise in terraforming. A practice mission for Mars.

[Solauren]

Water on Mars is good for helping with outer system water supplies, terraforming/colonization of mars, but I can't see it being used on Earth economically under current technology