This false color image, taken by NASA's Phoenix Mars Lander's Surface Stereo Imager, was taken on the 131st martian day, or sol, of the mission (October 7, 2008). The image shows color variations of the trench, informally named "La Mancha," and reveals the ice layer beneath the soil surface. The trench's depth is about 1.9 inches (5 cm) deep.
The color outline of the shadow at the bottom of the image is a result of sun movement with the combined use of infrared, green, and blue filters.
NASA/JPL/Universities of Arizona & Texas A&M