GURPS Space - assistance

[David Johnston2]

Originally Posted by Brett

It's interesting, but I wonder how quickly the oxygen atmosphere can develop without oceans and without forests.

Oceans are actually a big barrier to oxygenation because they contain so much dissolved material that oxidizes. The real question (assuming that initial life can come from offworld) is how you put enough lichen down when most of the world only gets rain as a freakish occurence.