Mark said:

>Space - its about survival not just curiosity. This is part of why the
>space program should focus on colonization potential (where Mars wins hands
>down over any other site in the solar system) not just scientific potential
>(where Mars is also near the top of the list, but not in a class of its
>own).

We could spend a trillion dollars creating a NEO defense system and then get
waxed by comet against which there is no credible defense. However I think the danger of NEOs is insignificant compared to the danger of some newly designed organism getting out of control. Mars colonization is an excellent insurance policy against many potential threats, most of which are unforseeable.

Gary