[JCThoughtscream]

Before we colonize anything outside of our own self-sustained gravity well, we kind of need to have a working model of a self-sustained /ecological system/.

Which we noticeably lack.

Let's not forget that, under the criteria of self-sustainment, Biosphere II was a failure, yes? And that subsequent research in ecological systems indicate that we are, collectively, more ignorant than wise as to the mechanics necessary to sustain a fully functional off-world environment.

Yes, we could be wiped out by a kilometer-radius asteroid at any moment. That doesn't mean we actually know what to do about it. Colonizing other planets necessitates /self-sustaining/ colonization - it's utterly pointless, after all, to have a Mars colony doomed to a slow and painful death if its ludicrously expensive supply line to Earth collapses.

If that doesn't convince you, though, /you/ can be the first one to try out a Biosphere-3 on Mars. Go ahead - I won't take your place in line. I promise.

[indrax]

You might be right, but none of that speaks against the urgency of doing it, or explains why people don't see it.

[foljs]

Practical chances of having something done affects the sense of "urgency to do it".

Even more urgent than colonization is the achievement of immortality, but I don't see people urging to achieve it for the same reason, i.e they think it's not practically achievable.

[gte910h]

I will have to say, even having a highly dependent colony on another planet will push towards self-sufficiency for pure cost reasons alone.