Before 1979 when Voyager 1 transmitted a single photograph of Jupiter's rings, Saturn was the only known planet with a ring system. Since that time, Jupiter's rings have been observed in detail from several spacecrafts, including Voyager 2, Galileo and New Horizons, as well as the Hubble Space Telescope. Scientists have also discovered rings on Uranus and Neptune, which means all the gas giants, which are planets composed mostly of gas, have a ring system.
Comparing the Rings
Saturn tops the charts with seven clearly defined rings that are visible from earth. This spectacular ring system was likely created by space debris that was caught in the gas giant's gravitational pull. In contrast, Jupiter possesses only four faint rings that aren't as clearly separated. According to data from the Galileo spacecraft, these rings were likely caused by impacts on nearly moons, which kicked up debris that now orbits the massive planet.