Phil said:

"I think Bigelow has got it wrong here. NASA has managed to obliterate 2 entire shuttle crews* while simply repeating the old LEO round and round trip time and again, huddled near Earth"

I'm reminded of a funny calculation that I did long ago. The question is raised: Through advanced medical science, what's the longest reasonable human life span? With bodies that don't age, at some point everybody dies from accidents. If we could theoretically live for thousands of years then after a century or two the survivors would be super conservative about safety, e.g. we'd all walk to work wearing helmets and flak jackets. However there are basic accidents that can't be avoided, e.g. slipping in the bath tub. A remarkably large number of people die evey year due to slipping in the bath tub. I looked at some accident statistics and estimated probable life span assuming the prime mode of death was slipping in a bath tub. My conclusion was that a life span of 350 years (give or take 50 years) was a reasonable expectation. Based upon this result, it is unreasonable to medically expand human life expectancy beyond 400 years.

Anyway, Space Exploration is intrinsically dangerous. An astronaut can die during reentry from LEO or from radiation induced cancer while living on Mars. If you ask the astronaut, I suspect he'd tell you that he'd rather die on Mars (I would!).

Gary