This image, combining data from two instruments aboard NASA's Mars Global Surveyor, depicts an orbital view of the north polar region of Mars.
The ice-rich polar cap seen at the center of the image is approximately 1,000 kilometers across. The white cap is riven with dark, spiral-shaped bands, visible as deep troughs that are in shadow.
To the right of center, a large canyon, Chasma Boreale, almost bisects the ice cap. Chasma Boreale is about the length of the United States' famous Grand Canyon and up to 2 kilometers deep.
July 31, 2012 8:23 AM PDT
Photo by: NASA/JPL-Caltech/MSSS
| Caption by: James Martin
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