Reull Vallis (from the Gaelic word for planet) located in the Promethei Terra region of Mars' cratered southern hemisphere flows for over 1,000 km towards the Hellas basin. This THEMIS image shows a portion of the channel with its enigmatic lineated floor deposits. These deposits are most likely rich in volatiles such as ice. The southern wall of the channel exhibits an obvious spur and gully topography. Several round impact craters are visible on the channel floor. Numerous crescentic features are also observed on the floor material. Could these crescentic features be older flow distorted craters? The THEMIS team will continue to study these features in detail.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.