Mars Global Surveyor
Mars Orbiter Camera

MOC--The First Year--Top 10

Polar Regions: Layered Deposits in North Polar Cap


Mars Global Surveyor Mars Orbiter Camera Release:          MOC2-81
Mars Global Surveyor Mars Orbiter Camera Image ID:         586335198.46103

360 Kbyte GIF


Layered sediment and ice cores are used by geologists to read the record of Earth's history and past climate. The martian north and south polar regions are covered by large areas of layered deposits that consist of a mixture of ice and dust. Since their discovery in the 1970s, these polar layered deposits have been cited as the best evidence that the martian climate experiences cyclic changes over time. It was proposed that detailed investigation of the polar layers (e.g., by landers and/or human beings) would reveal a climate record of Mars in much the same way that ice cores from Antarctica and Greenland are used to study past climates on Earth. In January 1999, NASA's Mars Polar Lander and Deep Space 2 Penetrators will be launched to go to Mars and study the upper layers of these deposits in the martian southern hemisphere.

Meanwhile, investigation of the north polar layered deposits has advanced significantly this year with the acquisition of new high resolution MOC images that reveal many more layers than were previously known to occur in the north polar deposits. MOC image 46103 (above) provides an example of the new data obtained in July, August, and September 1998. The picture shows a slope along the edge of the permanent north polar cap that has dozens of layers exposed in it. The image shows many more layers than were visible to the Viking Orbiters in the 1970s. The layers appear to have different thicknesses (some thinner than 10 meters (33 feet)) and different physical expressions. Some of the layers form steeper slopes than others, suggesting that they are more resistant to erosion. All of the layers appear to have a rough texture that might be the result of erosion and/or redistribution of sediment and polar ice on the slope surface.

MOC image 46103 was obtained on July 30, 1998. The scene covers an area approximately 2.9 km by 1.5 km (1.8 mi by 0.9 mi). The image center is located near 79.1°N, 340.8°W. (CLICK HERE for context image). Illumination is from the right. This picture was the subject of an earlier MGS MOC image release on October 19, 1998.

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.

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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