A manganese ring shows Mars' Utopia Planitia once held a stable ocean for around one million years, long enough for life to ...

Mars may have once had an ocean so vast that it covered one-third of the planet before evaporating billions of years ago and leaving behind a telltale sign: a flat band of land, outlining the former ...

A colossal valley near Mars’s equator is revealing dramatic clues about the Red Planet’s watery and volcanic past. Stretching ...