Voyager Encounters Jupiter

by United States. National Aeronautics and Space Administration

Ganymede

Ganymede, largest of Jupiter’s 13 satellites, has bright “young” ray craters; light, linear stripes resembling the outer rings of a very large, ancient impact basin; grooved terrain with many faults; and regions of dark, heavily cratered terrain. Among the Galilean satellites, Ganymede probably has the greatest variety of geologic processes recorded on its surface and may be the best example for studying the evolution of Jupiter’s inner satellites. Imbedded within Jupiter’s magnetosphere, Ganymede is subjected to the influences of the corotating charged-particle plasma and an interaction may exist with this plasma. No atmosphere has been detected.