Jupiter 2

Jupiter 2

Jupiter has at least 16 moons, the four largest of which are the Galilean moons: Io, Europa, Callisto, and Ganymede. They are called Galilean moons because they were first spotted by the great astronomer Galileo. His primitive telescopes were too primitive to have let Galileo see the smaller moons. Jupiter also has rings, though not nearly as visible or complex as those of Saturn. Jupiter gives off roughly twice as much radiation as it receives from the sun, due to the slow continual contraction of its giant atmosphere. [TB] {EA}