Adrastea, discovered in photographs taken by Voyager 2 July 8, 1979, is the small of the inner four moons of Jupiter. It is the first natural moon to be discovered by images taken by a spacecraft, instead of a telescope. Two more inner moons Thebe and Metis were discovered in images taken by Voyager 1 a few months earlier.
It has a strange shape, measuring 20x16x14 km across. It orbits Jupiter every 7 hours.
