NASA's Mars Exploration Rover Spirit took this grey-scale panoramic camera image on sol 100, April 14, 2004. It captures Spirit's future destination at the highlands informally named "Columbia Hills". In this image, the hills are approximately 2.4 kilometers (1.5 miles) to the southeast. Scientists believe the hills may consist of different and potentially older rock units than the basalts that Spirit has observed so far.
Image credit: NASA/JPL/Cornell