[extropy-chat] Mars and Titan

[Damien Broderick]

UK sf writer Adam Roberts mentioned in an interview his puzzlement that 
Titan (diameter 5150 km, 0.4 of Earth) has an atmospheric pressure at the 
surface 60% *greater* than Earth's, while Mars (6794 km, 0.53 Earth) has 
negligible atmosphere.

Hmm. How so? Is solar wind the culprit, far less intense at 9.5 AU than at 
1.5? You'd expect Saturn to rip the air away, but maybe it outgasses itself 
and helps keep Titan pumped up?

Damien Broderick