NASA’s Mars Rovers Pass the 50,000-Picture Mark NASA

A view of the sundial-like calibration target on NASA’s Mars Exploration Rover Spirit, with a bit of martian terrain in the background, is the 50,000th image from the twin rovers that have been exploring Mars since January. The images stock a treasury of scientific information on scales from microscopic detail to features on the horizon scores of kilometers or miles away, and even include glimpses of Mars’ moons, Earth and the Sun. They also provide an always-current understanding of the surrounding terrain for use by the team of rover wranglers planning each day’s activities on Mars.