Mark -

You might want to take into consideration that Robinson's "Red Mars" contains many science "howlers", and put your thinking about Mars on a more scientific basis.

The radiation load on the surface of Mars is enough to "varnish" rocks. That's what happens when raw solar plasma hits. There will be no green houses on Mars as Robinson envisioned.

This is not to say that there is no life on Mars, it just may be sub-surface, and thus ruling out back-contamination will be a very difficult problem, another problem which Robinson assumed away.

The working fluid on Mars appears to be CO2. While that means that there is some sub-surface water, Mars does not have aquifers as Robinson envisioned.

There is no indication that the human body can long thrive under 1/3 Earth gravity, another problem which Robinson assumed away in one sentence.

Mars does not have much of an atmosphere to speak of, and there is no way that people are going to run around on its surface in modified pressure suits as Rlbinson envisioned. Think Apollo Moon suits, and since Mars has twice the gravity as the Moon, these are going to weigh twice as much.

Now you might want to live in a fantasy world, but its not likely that O'Keefe does.

Also in the real world, the Earth gets hit fairly often by chunks of space stuff, and large numbers of people die.

EP
http://www.geocities.com/epgrondine