关于这张图
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 occurred early in Callisto's history; however, the central zone shown here is probably younger than Valhalla's surrounding structure. This newly [sic] acquired picture shows some s…