The McMurdo Dry Valleys are a row of valleys west of McMurdo Sound, Antarctica. They are so named because of their extremely low humidity and lack of snow and ice cover. Photosynthetic bacteria have been found living in the relatively moist interior of rocks. Scientists consider the Dry Valleys to be the closest of any terrestrial environment to Mars. Wright Valley extends across the image from lower left to upper right. To the left of it, and partially fog-covered, is Victoria Valley. The image was acquired December 8, 2002, covers an area of 58.5 x 64.9 km, and is located at 77.5 degrees south latitude, 162 degrees east longitude.