The rings of Uranus are thought to be relativity young, not more than 600 million years old. The uranium ring system probably began from the collisional fragmentation of Moons that once existed around the planet. After colliding , the Moons survived as narrow , optically dense rings only in zones of maximum stability. In 1986 , NASA’s voyager 2 visited Uranus. The visit is the only attempt to investigate the planet from a short distance. Uranus has 27 known Moons. The names for these Moons are chosen from characters from the works of Shakespeare and Alexander pope. Many Moons have yet to be discovered. They remain a mystery.