A rock containing many smaller round stones could indicate that there was once a large amount of liquid water on the Red Planet.

A Martian spacecraft spied a Martian rover rumbling through the red desert. The new image captured by NASA's Mars Reconnaissance Orbiter — which has orbited Mars since 2006 — shows the space agency's car-sized Curiosity rover traversing the terrain below as it scales the planet's 3.4-mile-high Mount Sharp.