Observations of Saturn's Ring-Plane Crossings in August and November 1995

Abstract

Observations of Saturn's ring system with the Hubble Space Telescope during the 10 August 1995 Earth crossing and the 17 to 21 November 1995 solar crossing indicate that the F ring dominates their apparent edge-on thickness of 1.2 to 1.5 kilometers. The F ring is slightly inclined with respect to the A ring, which may explain the approximately 50-minute difference in apparent crossing times for the east and west ring ansae in August. Prometheus lags its predicted position by about 19 degrees in longitude. The faint G ring is neutral or reddish in color and is confined to a radial range of 2.72 to 2.85 Saturn radii. The broad, distinctly blue E ring flares outward to a maximum thickness of about 15,000 kilometers at 7.5 Saturn radii and appears to have a spatially uniform particle size distribution.