NASA Mars Picture of the Day: Martian Gullies 05-08-2004

Mars Global Surveyor Mars Orbiter Camera

MGS MOC Release No. MOC2-720, 8 May 2004

NASA/JPL/Malin Space Science Systems

This March 2004 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC)
image shows a gullied crater wall at southern mid-latitude
near 35.5°S, 223.0°W. Formation of such gullies
might have involved flowing liquid water. The Mars science
community has been debating, since they were
first reported in June 2000, whether such
gullies were carved by water, carbon dioxide, or perhaps
formed in completely dry, granular material without the
influence of a fluid. The scientists have also debated whether
the water–if it was water–started out in the form of
ground ice, a snow pack, or liquid groundwater. Since
June 2000, many hundreds of new gully locations–and tens
of thousands of individual gullies–have been identified.
Their relative youth suggests to some the possibility that
Mars today has water or ice within less than 1 kilometer
of the surface–a depth that may be
readily accessible to future explorers.
This picture is illuminated by sunlight from the upper
left and covers an area about 3 km (1.9 mi) across.

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.