T his heat given off my Jupiter greatly affected the formation of the moon and satellites that orbit around Jupiter. Satellites that are close to the planet have more rocky, dry conditions; and those that are located farther away are more icy. This is best proven by the Galilean moons discovered by Galileo Galilei in 1620. The regular, circular, equatorial orbits of these satellites suggest that they must have formed from a cloud of small particles circling the planet.

J upiter's rings are very diffuse. The particles that make them up most on be a few microns big (about the wavelength of light). Because of there size, they are constantly spiraling down toward the planet. Scientist believe that these are resupplied by debris from the collision of asteroids and Io's volcanic ejecta or possibly micro meteoroids. There are believed to be many boulder-sized asteroids orbiting Jupiter .The bright ring may contain particles of a wide range of sizes, with two satellites found by the Voyager spacecraft near the ring's outer edge being the largest.