When the Mars rovers Spirit and Opportunity were launched in 2003 to look for water on the red planet, nobody knew for sure whether the technology would work.

But to the delight of Nasa scientists, the robots survived several Martian winters, mechanical break downs and many other challenges to send an ongoing stream of images from the surface.

To celebrate the 10th anniversary of the rover landings, a selection of those images is being exhibited at the National Air and Space Museum in Washington.

And as Jane O'Brien reports, they offer a remarkable picture of how the planet Mars has evolved.

Produced by the BBC's Franz Strasser.

Images courtesy of NASA/JPL-Caltech/Cornell University