Quote Originally Posted by CBR View Post
We don't need to colonize space to stop asteroids. A good early warning system in the form of telescopes dedicated to searching the sky for such objects will give us lots of time to deal with it.

AFAIK such telescopes are coming on line within a few years and are expected to pick up a few 100K asteroids we haven't picked up yet.

With several years warning time it only takes a small push to change the orbit enough to prevent a hit. A large mirror to melt a small part of a comet or perhaps an ion engine on an asteroid should be enough.

As for now there are no resources to get from space so that is not the point of going there. The point would be to set ambitious goals so new technologies are developed in the process. IMO we get more out of a billion spent on a new probe than a billion spent maintaining expensive Space Shuttles. That doesn't mean that manned spaceflight shouldn't be done of course.


CBR
The problem is the 'several years warning' bit. Space is a big place and we don't catch everything in it. Remember a few years ago, that asteroid that passed within, like 40,000 miles of us and nobody noticed until it was a week away or so?