SPRG Seminars
April 1, 2014:
"Titan's Interaction with its Surrounding Plasma Environment"
Stephen A. Ledvina, Space Sciences Laboratory, University of California, Berkeley
Titan is the largest moon of Saturn. It is the only moon in the solar system that has a substantial atmosphere with an approximate surface pressure of 1.5 atm. Titan's atmosphere is ionized forming an ionosphere that interacts with the plasma and magnetic field in Saturn's outer magnetosphere. The interaction is kinetic with gyroradii of the incident plasma is on order of a Titan radius. As Titan's ionosphere interacts with its surrounding environment an induced magnetosphere forms around the moon. The interaction leads to the loss of Titan's ionospheric plasma to the magnetosphere. Understanding the details of this plasma interaction is one of the primary goals of the Cassini mission. To date there have been over 100 Titan flybys by Cassini. The resulting observations have shown that Titan's plasma interaction is far more complicated than initially thought. To further our understanding of the interaction multispecies hybrid (kinetic ions, fluid electrons) simulations has been developed that includes the key physical and chemical processes occurring in Titan's ionosphere. A review of the Cassini observations will be given, followed by a description of the simulations and concluding with the insights the simulations provide about Titan's plasma interaction.