Cassini spacecraft shows nearly the full extent of Ithaca Chasma, a surface feature on Tethys, a moon of Saturn. The huge gash slices along over 620 miles (1,000 kilometers) of the moon's icy surface.

Powerful forces must have ripped apart the surface of Tethys at some time in the distant past, creating the astonishing canyon system of Ithaca Chasma.

Many impact craters speckle the canyons, which erase the older tectonic features and attest to the rift's great age.

Cassini spacecraft narrow-angle camera took the image in visible green light on July 28, 2008. At that time, the spacecraft was approximately 101,000 miles (163,000 kilometers) from Tethys.

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— NASA/JPL/Space Science Institute and SPACE.com Staff

Credit: NASA/JPL/Space Science Institute