Plasma environment at Titan's orbit with Titan present and absent

Abstract

To understand the possible large scale influence of Titan on its plasma environment, we study the magnetic fields and plasma measurements, both when Cassini flies close to Titan and when Cassini crosses the moon's orbit far from it. Using 98 Cassini passes from 06/2004 to 12/2008, we examine the plasma environments at the orbit of Titan with the moon present and absent. In particular, the presence of Titan appears to affect the magnetopause location. Near noon, the Saturn magnetopause is more frequently inside of Titan's orbit with the moon absent than with it present. Titan's presence near noon appears to locally enhance the total pressure and reduce the magnetosphere compressibility, possibly by mass-loading. Near local midnight, the stretching and sweepback angles for cases with Titan present and absent suggest that the moon enhances the tail reconnection rate, in agreement with previous studies of the moon's influence on the Saturnian magnetosphere.