my kids are going to space

[Baron Munchausen]

Gandalf Parker said:
The chances of finding a world that can be terraformed are much smaller than one that can be colonized. But terraforming isnt totally needed for colonization.

Besides, even on earth there are microbes that live in deadly extremes of gases, heat, cold, pressure, darkness, everything as long as there is water. And microbes can be used to create atmosphere I think.

Don't you mean this the other-way 'round? It seems to me that the chances of finding worlds close to our required environment but not 'perfect' are much higher than the chances of finding ready-to-colonize worlds.

The problem with terraforming is that not only do you have to change the world initially, you have to maintain it in the habitable condition you want/need. Think: If Mars currently has almost no atmosphere, how fast would an earth-like atmosphere bleed away into space? In a historical time-scale, very quickly.