Magnetospheric Consequences of Charged Ice Grains from the Enceladus Plume
Friday, 19 December 2014
Based on Cassini’s multiple instrument observations, we have studied the size distributions, densities, dynamics and currents of the ice grains from the Enceladus plume (Dong et al., 2014, submitted to JGR). Due to the charged grains’ large gyroradii (>> RE), they carry most of the negative charge away from the picked-up ion flow, which leads to a current system different from the ion pick-up and Birkeland current system. We will study the grain and ion currents based on their motion, develop a self-consistent current system near Enceladus, and estimate the consequent electromagnetic perturbations. Comparing the modeled magnetic perturbations with the MAG data may determine the magnitude of the total grain current, which in turn will give constraints on the grain charge density to compare with RPWS-LP plasma data in the plume.