Jupiter's Moons Thebe, Amalthea, and Metis

Explanation: The robot spacecraft Galileo in orbit around Jupiter has recently photographed the inner moons of Jupiter in greater detail than ever before. These pictures of Thebe , Amalthea , and Metis are shown to scale, and reveal details as small as three kilometers across. Amalthea , by contrast, has a total length of about 200 kilometers. The moons are composed mostly of ice, are much smaller than Jupiter's more famous Galilean satellites ( Io , Europa , Ganymede , and Callisto ), and orbit between Io and Jupiter's rings . Thebe appears dominated by a huge impact crater 40 kilometers across. Astronomers are uncertain of the origin of the unusual white gash at the bottom of Amalthea .