Pastel colors swirl across Mars, revealing differences in the composition and nature of the surface in this recently taken false-color infrared THEMIS image. Showing an area 31.9 kilometers (19.8 miles) by 88.3 kilometers (54.9 miles) in the southern highlands of Mars, the image is a result of the earlier orbit time for Mars Odyssey and THEMIS. In the image, dark areas mark exposures of relatively cold ground with abundant bare rock, while warmer basaltic sand covers the light blue-green regions. Reddish areas likely have a higher silica content, due either to a different volcanic composition or to weathering.