Mars may have once held a vast ocean across its northern lowlands, and the clearest clue may not be the faint shoreline ...

Scientists have found new evidence that Mars may once have been home to a vast ocean covering about one-third of the planet.

Mars may have once had an ocean so vast that it covered one-third of the planet before evaporating billions of years ago and ...

Scientists edge closer to answering Mars’ biggest question: Did life ever exist on the red planet? Here's the latest from two ...

A huge geological structure on Mars resembling a bathtub ring may be evidence of an ocean that once covered a third of the ...

The ancient ocean on Mars probably occupied a third of its surface.

By Will Dunham WASHINGTON, April 15 (Reuters) - There is a lot of evidence from orbiting satellites and surface rovers ...

Add Yahoo as a preferred source to see more of our stories on Google. When you buy through links on our articles, Future and its syndication partners may earn a commission. An illustration of Mars as ...

A new map reveals a blue Mars three billion years ago and strengthens the evidence of an ancient ocean that covered much of ...

Scientists have long known that Mars once had liquid water, but whether it formed only lakes and rivers or vast oceans has remained uncertain.

Caltech researchers have identified geological features on Mars that could point to the existence of a long-dried ocean that ...

The red planet was half blue, according to space scientists. A research team using images from cameras on Mars-orbiting spacecraft say it was a "blue planet" around three billion years ago – with an ...