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

Captured by the Orbiter's High-Resolution Imaging Science Experiment (HiRISE) camera, the shot was taken on February 28 this year; this was the 4,455th day of Curiosity's mission after it touched down on Mars on August 6, 2012.

NASA's Mars Reconnaissance Orbiter captured a stunning image of the Curiosity rover in motion, revealing its winding trail across the Martian surface. The rover, heading towards a region with potential signs of ancient groundwater activity,