Mars Global Surveyor
Mars Orbiter Camera

Mars Orbiter Camera (MOC) High Resolution Images:
Springtime Close-up of Layers in the South Polar Ice Cap


Mars Global Surveyor Mars Orbiter Camera Release:          MOC2-37A, -37B, -37C
Mars Global Surveyor Mars Orbiter Camera Image ID:         567516813.7306

(A) Portion of Viking Orbiter 2 image 421B77, reproduced here at full resolution of about 153 meters (500 feet) per picture element. The outline of the Mariner 9 image, (B), is shown. North is toward the upper left, sun illumination is from the upper left.


(B) Highest-resolution pre-Mars Global Surveyor view. Image is a portion of Mariner 9 DAS #8331829. It is shown here at full spatial resolution of about 99 meters (324 feet) per pixel. Box indicates location of MOC image (C). North is toward the upper left.


(C) Subframe of MOC image 7306 reproduced at full resolution, about 25 meters/pixel (81 feet/pixel). Picture shows an area approximately 15 x 14 km (9.3 x 8.7 miles) in size. Sun illumination is from the lower right.

You may need to adjust the images for the gamma of your monitor to insure proper viewing.

Note: This MOC image is made available in order to share with the public the excitement of new discoveries being made via the Mars Global Surveyor spacecraft. The image may be reproduced only if the image is credited to "Malin Space Science Systems/NASA". Release of this image does not constitute a release of scientific data. The 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.

Click Here for more information on MGS data release and archiving plans.


The linear features that run from the lower left to upper right in the MOC image are layers that have been exposed by erosion. The various textures among the layered deposits in the permanent south polar ice cap suggest that the different layers may have different compositions or physical properties (e.g., some may be "harder" or "softer" than others).

This image was taken during the spring season; the layers were still covered with ice/snow and appeared bright. The Mariner 9 context image (B) from 1972 and Viking 2 image (A) from 1977 show what this terrain looks like in the summer--the layered units are clear of seasonal frost and permanent ice and appear dark. Based on previous research, layers in the polar regions of Mars are thought to consist of a mixture of dust (~5%) and ice (~95%) that has accumulated over hundreds of millions of years as the polar caps grow and shrink each year.

Like sedimentary rocks on Earth, the layering might indicate a combination of changes in climate and changes in the type of material being deposited over time. These layers have much potential to provide clues about the past climate of Mars--so much so that the next U.S. spacecraft to land on Mars, the Mars Polar Lander, is scheduled to arrive in the south polar regions in December 1999.

The picture is a subframe of MOC image #7306, centered near 86.9°S latitude, 349.3°W longitude. It was taken on December 25, 1997, at 3:33 AM PST, on Mars Global Surveyor's 73rd orbit around Mars. The subframe covers an area about 15 x 14 km (9.3 x 8.7 miles) at about 25 m (81 feet) per picture element.

This image was featured as Figure 6b 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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