Image right: A sea of dunes, sculpted by the wind into long lines, surrounds the northern polar cap of Mars, covering an area as big as Texas. In this false-color image, areas with cooler temperatures are recorded in blue tints, while warmer features are depicted in yellows and oranges. This scene combines images taken between 2002—2004 by the Thermal Emission Imaging System instrument onboard NASA’s Mars Odyssey orbiter. In December, 2010, Mars Odyssey became the longest-serving spacecraft at the Red Planet. From FETTSS Web site. (NASA/JPL-Caltech/Arizona State University)
