NASA Mars Picture of the Day: Gullies With Bright Material

Mars Global Surveyor Mars Orbiter Camera

MGS MOC Release No. MOC2-680, 29 March 2004

NASA/JPL/Malin Space Science Systems

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC)
image shows a set of south middle-latitude gullies in a crater
wall. Some of the gullies and the erosional alcoves that formed
above them have cut and exposed a light-toned material. In the larger
gully, this material has been transported down the slope,
through the channel, to give the
debris apron a lighter tone, as well. The origin of middle- and
polar-latitude gullies on Mars remains an area of active debate
and discussion within the Mars science community. Mass movement
of debris, everyone agrees, has occurred. Unclear are the
relative roles of water, ice, and carbon dioxide, if any,
in the processes that created the gullies.
These features occur
near 38.8°S, 40.3°W.
This February 2004 image covers an area about 3 km (1.9 mi) across.
Sunlight illuminates the scene from the upper left.

Malin Space Science Systems and the California Institute of Technology
built the MOC using spare hardware from the Mars Observer mission.
MSSS operates the camera from its facilities in San Diego, California.
The Jet Propulsion Laboratory’s Mars Surveyor Operations Project
operates the Mars Global Surveyor spacecraft with its industrial
partner, Lockheed Martin Astronautics, from facilities in Pasadena,
California and Denver, Colorado.