Mars Global Surveyor
Mars Orbiter Camera

Mars Orbiter Camera (MOC) Low Resolution Image:
Clouds over the Tharsis Volcanoes


Mars Global Surveyor Mars Orbiter Camera Release:          MOC2-39
Mars Global Surveyor Mars Orbiter Camera Image IDs:        564822000.4801
                                                           (P048-01, -02)

JPG = 252 KBytes

Warning: This color composite image does not represent the "true" color of Mars. MOC wide angle images 4801 (red-band) and 4802 (blue-band), and a green-band synthesized by averaging the red and blue bands, have been combined to create this composite.

Note: You may need to adjust this image or your monitor to account for gamma differences.

Note: The MOC images are made available in order to share with the public the excitement of new discoveries being made via the Mars Global Surveyor spacecraft. The images may be reproduced only if the images are credited to "Malin Space Science Systems/NASA". Release of an image does not constitute a release of scientific data. An image and its caption should not be referenced in the scientific literature. Full data releases to the scientific community are scheduled by the Mars Global Surveyor Project and NASA Planetary Data System. Typically, data will be released after a 6 month calibration and validation period.

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This wide-angle view from the Mars Orbiter Camera, centered on the giant volcano, Arsia Mons (8°S, 120°W), shows high-altitude, wispy, white clouds over the Tharsis volcanic region. The central caldera of Arsia Mons (i.e., the circular crater at the summit of the volcano) is about 120 kilometers (75 miles) across.

Diagonal from Arsia Mons (center) toward the upper right is another of the large Tharsis Montes volcanoes, Pavonis Mons. Smaller Biblis Patera and Ulysses Patera volcaoes are visible just left of center near the top of the picture. The dark spot toward the lower right is known as Solis Lacus ("Lake of the Sun"). The clouds are mostly likely composed of water ice rather than vapor. Clouds like these are common in the Tharsis region.

This picture was acquired by MOC on Mars Global Surveyor's 48th orbit at about 11 PM PST on November 23, 1997. A few days later, a major dust storm in the southern hemisphere warmed up the atmosphere such that clouds like those shown here did not form again until after the storm subsided.

This color composite of MOC images 4801 (WA red) and 4802 (WA blue) was featured as Figure 7b in Malin et al., "Early Views of the Martian Surface from the Mars Orbiter Camera of Mars Global Surveyor," Science, v. 279, no. 5357, pp. 1681-1685.

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.

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