Mars Global Surveyor
Mars Orbiter Camera
Springtime on the Martian South Polar Cap
MGS MOC Release No. MOC2-289, 21 September 2001
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC)
wide angle view of the martian south polar region was acquired
on September 12, 2001, four years to the day after MGS first
began to orbit the Red Planet. The bright area at the center
of the image is the permanent south polar cap---the part of the cap that
will remain through the coming summer. The bright areas that
surround the center make up the seasonal frost cap that was
deposited during southern winter, which ended June 17, 2001.
The dark area in the lower right corner results from two
phenomena--the seasonal frost is subliming away much faster
in this region, and the area is darker because it is closer
to the night side of the planet. The fuzzy or hazy zone that
covers most of the left side of the image consists of
afternoon clouds and fog. The polar frosts contain both
water and carbon dioxide ices. Clouds of condensing water
ice crystals are common over parts of the polar cap at this
time of year. For scale, the permanent cap at the center
of the image is about 420 km (260 mi) across. Sunlight illuminates
the scene from the upper left. For a summertime view of the cap, see
http://www.msss.com/mars_images/moc/4_27_00_spcap/.
Summer in the southern hemisphere will begin in mid-November 2001.
Image Credit: NASA/JPL/Malin Space Science Systems
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,
CA. 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, CA
and Denver, CO.
To MSSS Home Page
