NASA Mars Picture of the Day: Boulders on Phobos

Mars Global Surveyor Mars Orbiter Camera

MGS MOC Release No. MOC2-485, 16 September 2003

NASA/JPL/Malin Space Science Systems

In 1998, the Mars Global Surveyor (MGS) spacecraft made
four passes by the innermost of the two martian satellites,
Phobos. The fourth pass, made just over 5 years ago on
12 September 1998, offered the Mars Orbiter Camera (MOC)
the opportunity to acquire the highest resolution images
of the moon, ever. This wonderful 5-year-old picture highlights
the surface of Phobos. Several large boulders can be
seen, including a very
large one near the center that is about 85 meters (~280 feet)
in diameter. Most of the boulders may have been ejected from
the largest impact crater on Phobos, Stickney.
Sunlight illuminates the scene from the left/lower 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.