Rocks Rolling

This image covers where the southern branch of Shalbatana Vallis opens into Chryse Planitia, showing a variety of boulders that have moved down slope leaving tracks on the surface. These boulders may have been thrown out from low-energy secondary craters, or simply eroded out of the above rocky cliff.

In the subimage, the left frame shows boulders moving in two directions, indicating that they had different sources. The right frame shows a boulder about 4 meters in diameter in the bottom left, having left a track that begins in the upper right. This boulder rolled down the hill, appears to have jumped the crater, bounced a few times, and then rolled to a halt.

Written by: Ross A. Beyer   (8 April 2008)

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Image: NASA/JPL/University of Arizona