Atmosphere and gravity don't matter...
If you're underground or underwater. You have pressure from the fluid column above you (and rock and ice). You are naturally bouyant or neutral. You are a happy microbe...
Space/Science » in reply to re: Mars and Europa....
If you're underground or underwater. You have pressure from the fluid column above you (and rock and ice). You are naturally bouyant or neutral. You are a happy microbe...