Space / 1979-02-28
ARC-1979-A79-7027
NASA's image library records ARC-1979-A79-7027.
This photo of Callisto, outermost of Jupiter's four Galilean satellites, was taken a few minutes after midnight (PST) Feb. 25 by Voyager 1. The distance to Callisto was 8,023,000 kilometers (4.98 million miles). The hemisphere in this picture shows a fairly uniform surface dotted with brighter spots that are up to several hundred kilometers across.
A CLOSER LOOK
This photo of Callisto, outermost of Jupiter's four Galilean satellites, was taken a few minutes after midnight (PST) Feb. 25 by Voyager 1. The distance to Callisto was 8,023,000 kilometers (4.98 million miles). The hemisphere in this picture shows a fairly uniform surface dotted with brighter spots that are up to several hundred kilometers across. Scientists believe the spots may be impact craters but higher-resolution photos will be necessary before the features can be interpreted. Callisto is about the same size as the planet Mercury--about 5,000 kilometers (3,000 miles) in diameter. Callisto is less massive than Mercury, however, giving it a density less than twice that of water. Scientists believe Callisto, therefore, is composed of a mixture of rock and ice (up to about 50 percent by
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FOLLOW THE EVIDENCE
NASA Image and Video LibraryARC-1979-A79-7027Original explanation based on the sources above. Images carry their own reuse terms.