dipper@utastro.UUCP (Debbie Byrd) (05/25/85)
The fine particles in Jupiter's ring appear to flow toward Jupiter. More -- after this. May 25 Jupiter's Ring Yesterday we talked about the dark, narrow rings of the planet Uranus -- discovered in 1977. Besides Uranus -- and besides the well-known ringed planet Saturn -- Jupiter also has a ring -- discovered by the Voyager spacecraft when it swept past the giant planet in 1979. Decades before Voyager went to Jupiter, the idea of a jovian ring was suggested -- then generally ignored. Still, Voyager was directed to take pictures of the region right next to Jupiter -- to search for a possible ring, or unknown faint inner moons. It was a long shot -- but it paid off -- because a ring for Jupiter appeared in some of the pictures! The jovian ring may be analogous to a river flowing on Earth. A river is always visible -- but the water in the river continually changes as it flows toward the sea. Likewise, the fine particles making up Jupiter's ring appear to flow inward toward Jupiter. The brightest part of Jupiter's ring is located about 40 thousand miles above the planet's equator. The ring extends inward toward Jupiter for at least four thousand miles. The source of the particles in the jovian ring may be a small moon, located just outside the brightest portion. The particles may be knocked off the moon by impacts with other objects -- possibly meteorites. As the particles in the ring spiral toward Jupiter, new particles are knocked off the moon and become part of the ring -- so that Jupiter's ring can be a stable feature -- but continually made of new material. Script by Deborah Byrd. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin