MARS EVAPORATES: Reader Mostafa Sabet responds to my Mars posting over at GlennReynolds.com by asking:

One question I have regarding terraforming Mars is its ability to keep the brand-spanking new atmosphere we produce on Mars. I thought one of the reasons Mars’ atmosphere was so thin was that it did not have the gravitational pull to keep it. Wouldn’t we need to create some sort of additional, artificial gravity to keep all the air in? I know CF4 would probably remain in Mars’ atmosphere because of its weight, but what about O2. Granted in the decades (centuries) till the atmosphere could support animal life we might have the artificial gravity tech, but is there a solution short of this?

Granted, it’s been a while since I studied astronomy and you would probably know better than I. If what I asked is not the case, could you help pointing me to some related articles? Thanks for the help and I love the pointers. It depresses me that the most likely way for us to reach Mars is if the Chinese make a race out of this (and by then they’ll likely have a head start, too).

Well, Mars would lose its atmosphere gradually, but “gradually” in this context means over tens of thousands of years at least, as I understand it. I highly recommend Bob Zubrin’s books, starting with The Case for Mars, for more detailed information.

As for the idea that we’ll go because of Chinese competition, well, it’s not as depressing as the idea that we might not go at all. But, yeah, it’s depressing that it might take something like that.