A light scattering analysis of the cryovolcano plumes on enceladus

Abstract

Observations by NASA's Cassini spacecraft show that Enceladus, the sixth largest moon of Saturn, has cryovolcanoes on its south pole as well as a global subsurface ocean beneath Enceladus's icy crust. Photographs from the Imaging Science Subsystem (ISS) cameras aboard Cassini during flybys of Enceladus show cryovolcano plumes. The images are taken in several filters and with linear polarizers at various angles and orbital positions. Light scattered by the plume particles and observed by Cassini may provide information about the plume composition and potentially the dynamics of the ocean below. Here, we remove the coupling between orbital position and scattered plume intensity as well as analyze ISS data using light scattering models and the Q-space method. We suggest that the plume particles are generally larger than two microns in radius and nonspherical in shape.