Neptune has five planetary rings. The rings were named after astronomers that were instrumental in prime discoveries on Neptune. The names of the rings are Adams, Arago, Lassell, Le Verrier and Galle.
Astronomers did not definitively identify that Neptune had planetary rings until 1989, which was 143 years after its discovery. The rings of Neptune vary in width from 113 kilometers to 4,000 kilometers and are comprised primarily of dust and small pieces of rock. Scientists believe that Neptune's rings were formed from the debris of one of its moons, which was destroyed after coming in close contact with the planet.