The remarkable twin robotic rovers on Mars are still functioning and have sent more than 50,000 photos back to Earth: http://www.jpl.nasa.gov/news/news.cfm?release=2004-266 NASA's Mars Exploration Rover Spirit took the images that make up this mosaic with its panoramic camera on sol 161 (June 16, 2004). The view is looking southward and shows the etched terrain that makes up this landscape. The wall of Gusev Crater appears light gray and can be seen rising up against the horizon. This image was taken with the panoramic camera's blue (750-nanometer) filter. Its contrast was stretched.