Mars may have once held a vast ocean across its northern lowlands, and the clearest clue may not be the faint shoreline traces scientists have argued over for years. Instead, it could be a broad, ...

Using images from cameras on Mars orbiters, an international research team has discovered structures on Mars that are very similar to classic river deltas on Earth. These are traces of rivers that ...

Billions of years ago, water flowed across Mars. Most scientists agree the red planet had rivers. But did those rivers flow into an ocean? New research from the University of Arkansas found strong ...

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 ...