Ancient Mars Covered by Vast Ocean

[mickw]

More than 3 billion years ago, the northern plains of Mars were covered by a vast ocean that blanketed more than a third of the red planet's surface, new research suggests.

Previous spacecraft investigations have pointed to possible signs of an ancient ocean on Mars. Still, this idea has been challenged for decades, as past evidence has been uncertain, and the matter remains one of the greatest open questions when it comes to researching the red planet.

Now scientists have analyzed global databases of river valley networks on Mars, as well as deposits left behind by ancient deltas. Their research suggests 29 deltas they investigated -- more than half of all those in the databases -- sat at roughly the same height some 3.5 billion years ago, apparently ringing a vast ancient ocean shoreline in the northern lowlands of Mars

More:   Red Sea