Saturn's E, G, and F rings: Modulated by the plasma sheet?

Publisher Website
Google Scholar
Abstract
Saturn's broad E ring, the narrow G ring, and the structured and apparently time‐variable F ring(s) contain many micron and submicron‐sized particles, which make up the ‘visible’ component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. In addition, Coulomb drag forces may be important, in particular for the E ring. The possibility that electromagnetic effects may play a role in determining the F ring structure, and its possible time variations, is critically examined. Sputtering of micron‐sized dust particles in the E ring by magnetospheric ions yields lifetimes of 10² to 104 years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.