Parts of Mars were once 'drenched' with so much water that life could easily have existed there, NASA says.
The robot explorer Opportunity has seen clear evidence of the main goal of Mars exploration -- that water once flowed or pooled on the Red Planet's surface.
'Opportunity has landed in an area of Mars where liquid water once drenched the surface,' NASA associate administrator Ed Weiler told a news conference on Tuesday. 'Moreover, this area would have been good habitable environment.'
That does not mean that evidence of life has been found -- but it suggests that life could have evolved on Mars just as it did on Earth, NASA said.