Evidence for vast oceans on ancient Mars?
Sea here:
http://www.universetoday.com/2008/11/17/evidence-for-vast-oceans-on-ancient-mars/#comments
It would be hard to deny that there were some bodies of water on
Mars way back in its early days, even without the proof from the two
rovers.
It would seem a combination of the planet's smaller size, more distant
orbit, and a major impact about 3 billion years ago (which created the
Hellas Basin) did much to make Mars even less like Earth.
Now whether any life got started there or even survived the eons
is another story. Drilling for fossils may be our best bet to find out,
or getting to a subsurface water source.