Go to: MARS FINGERS Seeming to jut out like bright fingers over dark soil, these strange red planet formations, which are inside a large crater, are likely deposits of volcanic ash or windblown dust. The light sediments probably eroded from the adjacent dark sand regions according to planetary geologists. This picture, taken by the Thermal Imaging Emission System camera on the Mars Odyssey orbiter, extends about 6.2 miles (10 km). (07/31/02)