Temperature variations of Saturn rings with viewing geometries from Prime to Equinox Cassini Missions.

Abstract

After more than six years in orbit around Saturn, the Cassini Composite Infrared Spectrometer (CIRS) has acquired an extensive set of measruements of Saturn's main rings (A, B, C and Cassini Division) in the thermal infrared. Temperatures were retrieved for the lit and unlit rings over a variety of ring geometries that include phase angle, solar and spacecraft elevations and local time. We show that some of these parameters (solar and spacecraft elevations, phase angle) play a role in the temperature vatiations in the first order, while the others (ring and particle local time) produced second order effects. The results of this comparison will be presented.