Was Mars ever warm enough for this?
I saw this article the other day that suggests that whilst there was water on the surface of Mars it was always ice.
http://www.iflscience.com/space/icy-mars-theory-strikes-back
Seems plausible to me, unless Mars had a really hot core in the past it was never going to get much energy from the Sun to give it the seas and oceans that are often depicted.
Biting the hand that feeds IT
