The Shape of Saturn's B Ring Edge from Voyager, Earth-based, and Cassini VIMS, UVIS, and RSS Occultations
Abstract
The outer edge of Saturn's B ring is strongly distorted by the nearby 2:1 Mimas inner Lindblad resonance, which helps to confine the ring. Previous studies based on Cassini ISS images [Spitale and Porco 2010, Astron. J. 140, 1747] and on an extensive set of ring occultation observations from 1980-2010 (including Voyager, Earth-based observations, and Cassini RSS, UVIS, an VIMS results from 2005-2010 [Nicholson et al. 2014, Icarus 227, 152]) independently showed that the m=2 distortion circulates slowly relative to Mimas in a prograde direction, with a radial amplitude varying from just 3 km to a maximum of about 71 km, with short-lived minima recurring every 5.42 years. Additionally, the ring edge has an elliptical (m=1) distortion with a radial amplitude of ~20 km, and weaker normal modes with wavenumber m=3, 4, and 5. Here, we extend the range of the observations to include a comprehensive set of occultation observations from the entire Cassini mission, spanning 2005-2017. This provides coverage of an additional complete circulation cycle beyond the Nicholson et al. (2014) study. With this expanded time scale, we explore the persistence of periodic variations in the shape of the B ring edge over nearly 40 years of observations.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.P23C3511F
- Keywords:
-
- 6022 Impact phenomena;
- PLANETARY SCIENCES: COMETS AND SMALL BODIES;
- 6213 Dust;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6245 Meteors;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6265 Planetary rings;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS