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Galileo's Legacy at Jupiter

artist's concept of Galileo at Jupiter
A Detailed View of Callisto's Surface

This mosaic of two images shows an area within the Valhalla region on Jupiter's moon Callisto and illustrates one of the most significant discoveries of Galileo. There is an unexpected absence of small craters and clear evidence in the ragged rims of the craters of an erosion process that is believed to be due to sublimation of volatiles from the surface ice. North is to the top of the mosaic and the Sun illuminates the surface from the left. The mosaic covers an area approximately 33 kilometers (20 miles) across. Scientists believe Valhalla is the result of a large impact early in the history of Callisto. The Solid State Imaging System aboard NASA's Galileo spacecraft obtained these images on November 4, 1996.