English: View of Melas Chasma, with parts of Ius, Candor and Coprates chasmata visible at the upper left, top and lower right, respectively, parts of the enormous Valles Marineris canyon system on Mars. This image was obtained by cropping a massive 23,711 × 11,856 pixel mosaic of NASA images, and adjusting in hue and saturation. The original caption for the mosaic reads in part as follows:

This mosaic image of Valles Marineris - colored to resemble the martian surface - comes from the Thermal Emission Imaging System (THEMIS), a visible-light and infrared-sensing camera on NASA's Mars Odyssey orbiter. Mars Odyssey was built by Lockheed Martin and the mission is operated by the Jet Propulsion Laboratory.

Built from more than 500 daytime infrared photos, the mosaic shows the whole valley in more detail than any previous composite photo. Despite the valley's huge extent - including its western extension through Noctis Labyrinthus, it reaches some 3,000 kilometers (2,000 miles) long - the smallest details visible in the image are about the size of a football field: 100 meters (328 feet).