Enceladus is the sixth-largest moon of Saturn. It was discovered in 1789 by William Herschel. Until the two Voyager spacecraft passed near it in the early 1980s, very little was known about this small moon besides the identification of water ice on its surface. The Voyagers showed that the diameter of Enceladus is only 500 km, about a tenth of that of Saturn's largest moon, Titan, and reflects almost 100% of the sunlight that strikes it. Voyager 1 found that Enceladus orbited in the densest part of Saturn's diffuse E ring, indicating a possible association between the two, while Voyager 2 revealed that despite the moon's small size, it had a wide range of terrains ranging from old, heavily cratered surfaces to young, tectonically deformed terrain, with some regions with surface ages as you