Avalanches of rock and dust scar the sides of mesas in Mars' Noctis Labyrinthus badlands, in a false-color view taken by THEMIS, the Thermal Emission Imaging System, aboard NASA's Mars Odyssey orbiter. This THEMIS nighttime temperature image shows warmer areas in redder colors and colder areas in bluer tones. Temperature images help scientists distinguish dust-covered surfaces from rocky ones: dust cools quickly at night on Mars, while rocks retain daytime heat. Here the colors show a jumble of Sun-warmed rocks deposited by landslides where several channels join. On the slopes above, rocks mix with cooler dust, while on the mesa tops, cold dust generally prevails. Credit: NASA/JPL/Arizona State University.