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PHOTO CAPTION
P-48125
December 12, 1996

A portion of the central zone of the large impact structure Valhalla on
Jupiter's moon Callisto was imaged by the Galileo spacecraft on November 4,
1996. The area shown here is centered at 16 degrees north, 55 degrees west
and is about seven miles (11 kilometers) across. This is the highest
resolution picture ever taken of Callisto and shows features as small as 200
feet (60 meters) across. The formation of Valhalla occured early in
Callisto's history; however, the central zone shown here is probably younger
than Valhalla's surrounding structure. This newly acquired picture shows
some small craters, although they have been softened or modified by
downslope movement of debris, revealing bright ice-rich surfaces. In
contrast to other areas on Callisto, most of the very smallest craters
appear to have been completely obliterated.

This image was taken by the solid state imaging television camera onboard
the Galileo spacecraft during its third orbit around Jupiter, at a distance
of 757 miles (1,219 kilometers).

Launched in October 1989, Galileo entered orbit around Jupiter on December
7, 1995. The spacecraft's mission is to conduct detailed studies of the
giant planet, its largest moons and the Jovian magnetic environment. The Jet
Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of
Space Science, Washington, DC.