Comment Re:Can it produce oxygen? (Score 3, Interesting) 23
What I've heard as a rough estimate is that if somehow someone was able to give Mars a dense atmosphere (thicken it with water vapor, nitrogen and a whole more CO2 to create a greenhouse effect) it would probably endure for a million years, but without replenishment, eventually the solar wind will indeed just blow it away. As to create a sufficient magnetic field, well, I don't see how it's actually possible to create that large a magnetic field without a helluva lot of energy. I don't know if there is an engineering solution without magical far future technology to shield Mars' atmosphere from the solar wind. I've read of some guys suggesting we bombard the planet with comets and other debris to kick start the various cycles (carbon, nitrogen, water) as well as create a whole lot of heat to start melting the large amounts of water, but for that we're talking if not super far future planetary engineering, then at least we're talking about really big rocket engines (probably nuclear) shoving all kinds of gunk at Mars from every corner of the solar system.
Who knows, maybe in a few centuries the technology will exist to pull it off. Mars certainly seems the most likely body in the solar system to terraform. It is, by some estimates, still in the Goldilocks zone, so providing there's a sufficiently dense atmosphere with enough CO2 to actually capture more solar radiation, it might work. But it really would take a whole other level of technology to protect that atmosphere from steadily being eroded, and stop everyone from getting horrible cancers along the way.