This image of Phobos, the inner and larger of the two moons of
Mars, was taken by the Mars Global Surveyor on August 19, 1998. This
image shows a close-up of the largest crater on Phobos, Stickney, 10
kilometers (6 miles) in diameter. Individual boulders are visible on the
near rim of the crater, and are presumed to be ejecta blocks from the
impact that formed Stickney. Some of these boulders are enormous -
more than 50 meters (160 feet) across. Also crossing at and near the
rim of Stickney are shallow, elongated depressions called grooves. This
crater is nearly half the size of Phobos and these grooves may be
fractures caused by its formation. Phobos was observed by both the
Mars Orbiter Camera (MOC) and Thermal Emission Spectrometer (TES).
This image is one of the highest resolution images (4 meters or 13 feet
per picture element or pixel) ever obtained of the Martian satellite.
Malin Space Science Systems, Inc. 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 Thermal Emission Spectrometer is operated by Arizona State
University and was built by Raytheon Santa Barbara Remote Sensing.
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.
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