Mars: The planet that lost an ocean's worth of water
Thursday, March 5, 2015 - 14:30
in Astronomy & Space
About four billion years ago, the young planet would have had enough water to cover its entire surface in a liquid layer about 140 meters deep, but it is more likely that the liquid would have pooled to form an ocean occupying almost half of Mars’s northern hemisphere, and in some regions reaching depths greater than 1.6 kilometers.