Pastel colors swirl across Mars, revealing differences in the composition
and nature of the surface in this false-color infrared image taken on May
22, 2009,by the Thermal Emission Imaging System (THEMIS) camera on NASA's
Mars Odyssey orbiter.
The image shows an area 31.9 kilometers (19.8 miles) by 88.3 kilometers
(54.9 miles) in the southern highlands of Mars. It is a result of altering
the orbit of Odyssey so that the spacecraft passes over the day side of
Mars earlier in the afternoon, when the ground is warmer and thus emits
more strongly in the infrared frequencies detected by THEMIS. Prior to
beginning the slow shift in orbit on Sept. 30, 2008, Odyssey was looking
down at ground where the local solar time was about 5 p.m. When the shift
was completed, on June 9, 2009, the orbiter and camera were looking down
at ground where the local solar time is about 3:45 p.m.
In the image, dark areas mark exposures of relatively cold ground with
abundant bare rock, while warmer basaltic sand covers the light blue-green
regions. Reddish areas likely have a higher silica content, due either to
a different volcanic composition or to weathering.
NASA's Jet Propulsion Laboratory manages Mars Odyssey for NASA's Science
Mission Directorate, Washington, D.C. THEMIS was developed by Arizona
State University, Tempe, in collaboration with Raytheon Santa Barbara
Remote Sensing. The THEMIS investigation is led by Philip Christensen at
Arizona State University. Lockheed Martin Space Sciences, 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.