"If I understand the theory--create a human population on Mars in case of extinction on Earth, then it is not a good reason, BY ITSELF, for colonizing Mars."
Yes, I know.
"Obviously, if we had the technology for transferring the huge number of people to Mars required to create a viable permanent population, not to mention the technology required to support a permanent ecosystem, then we would be able to easily use the same technology to divert any approaching asteroids large enough to create an extinction scenario."
Right. The argument was first used for space exploration in general. For long term survival we must get off Earth. So getting into space isn't a question of "if" but of "when". And there is no better time than the present:).
"There are a lot of reasons to go to Mars, but I don't think this is one of them."
Skiing and mountain climbing seems like good reasons. The problem is we must first get out of Earth's gravity well.
Getting out of Earth's gravity well is presently too expensive. We must first lower this cost. I recently made a post at MSNBC which explains how I think it should be done.
http://bbs.msnbc.com/bbs/msnbc-space/posts/og/113062.asp
Of course this isn't a new idea for me- I've posted about it for at least a year now.
-gb
Space/Science » in reply to Lifeboat Theory--my 2 cents
two cents