Changes in a Dusty Ringlet in the Cassini Division after 2010

TL;DR

The paper reports significant changes in the structure and brightness variations of the Charming Ringlet in Saturn's Cassini Division between 2010 and 2012, indicating a disturbance event affecting its eccentricity and material distribution.

Contribution

It provides the first detailed analysis of the ringlet's structural changes and brightness variations after 2010, revealing a disturbance event that altered its eccentricity and material distribution.

Findings

Over 50% increase in free eccentricity component between 2010 and 2012.

Presence of a material shelf extending inward from the ringlet after 2012.

Longitudinal brightness variations rotating at different rates for at least 3 years.

Abstract

A dusty ringlet designated R/2006 S3, also known as the "Charming Ringlet", is located around 119,940 km from the center of Saturn within the Laplace Gap in the Cassini Division. Prior to 2010, the ringlet had a simple radial profile and a predictable eccentric shape with two components, one forced by solar radiation pressure and the other freely precessing around the planet. However, observations made by the Cassini spacecraft since late 2012 revealed a shelf of material extending inwards from the ringlet that was not present in the earlier observations. Closer inspection of images obtained after 2012 shows that sometime between 2010 and 2012 the freely-precessing component of the ringlet's eccentricity increased by over 50%, and that for at least 3 years after 2012 the ringlet had longitudinal brightness variations that rotated around the planet at a range of rates corresponding to roughly 60 km in orbital semi-major axis. Some event therefore disturbed this ringlet between 2010 and late 2012.