NASA rover finds 'clearest evidence yet' of an ancient lake on Mars

In the foothills of a Martian mountain, NASA's Curiosity rover found stunning new evidence of an ancient lake in the form of rocks etched with the ripples of waves — and the telltale signs appeared in an unlikely place.

The rover is traversing an area of Mars called the "sulfate-bearing unit" that researchers previously thought would only show evidence of mere trickles of water, as scientists believed the rocks there formed as the surface of the red planet was drying out.

Instead, the rover found some of the clearest evidence yet of ancient waters.

NASA rover finds 'clearest evidence yet' of an ancient lake on Mars

N﻿ASA has identified the site of an ancient lake on Mars, surrounded by mountains they say could have been ...

NASA has identified the site of an ancient lake on Mars, surrounded by mountains they say could have been ...