Neptune’s rings

Neptune’s rings

. As Voyager 2 left Neptune in August 1989, the planet’s narrow rings were backlit by the Sun, enhancing the visibility of the rings’ dusty particles. The outer ring consists of at least three dense clumps of orbiting debris, named Liberté, Egalité and Fraternité, that stand out from the thinner remainder of the ring. Astronomers on the ground had only detected the clumps during some stellar occultations, and assumed that the ring was incomplete. The outermost ring is named Adams, and the innermost is designated Le Verrier. They are named for John Couch Adams (1819-1892) and Urbain Jean Joseph Le Verrier (1811-1877) who independently predicted the existence of the then unknown planet Neptune. A third, fainter ring is located closer to Neptune than the two main rings; it has been named Galle after Johann Gottfried Galle (1812-1910) who found the planet close to both of Adams’ and Le Verrier’s predicted positions using a 0.23-meter (9-inch) refractor. (Courtesy of NASA and JPL.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University