HR: 08:20h
AN: P51E-02 INVITED     [Abstracts]
TI: The composition of Saturn's magnetosphere
AU: * Crary, F J
EM: fcrary@swri.edu
AF: Southwest Research Institute, 6220 Culebra Rd. , San Antonio, TX 78228 United States
AU: Goldstein, R
EM: rgoldstein@swri.edu
AF: Southwest Research Institute, 6220 Culebra Rd. , San Antonio, TX 78228 United States
AU: Reisenfeld, D
EM: dan.reisenfeld@umontana.edu
AF: University of Montana, Department of Physics and Astronomy 32 Campus Drive, Missoula, MT 59812 United States
AU: Sittler, E C
EM: Edward.C.Sittler@nasa.gov
AF: Goddard Space Flight Center, Goddard Space Flight Center, Greenbelt, MD 20771 United States
AU: Smith, H T
EM: hts4f@virginia.edu
AF: University of Virginia, Engineering Physics, Thornton Hall Charlottesville, VA 22904 , Charlottesville, VA 22904 United States
AU: Young, D T
EM: dyoung@swri.edu
AF: Southwest Research Institute, 6220 Culebra Rd. , San Antonio, TX 78228 United States
AB: Since July, 2004, the Cassini spacecraft has been orbiting Saturn and observing the planet, its satellites, rings, and its magnetosphere. Here we report on the initial survey of ion composition in Saturn's magnetosphere. The plasma, composed primarily of protons, oxygen and water group ions, also contains molecular hydrogen ions, helium, nitrogen, and other minor species. The abundance of the major ions varies with distance from Saturn. Inside of ~4 R_S the proton abundance is low, and the water group ions are primarily the heavier species such as H3O4. At greater distances, O+ becomes the most abundant heavy ion, and beyond ~10 R_S protons are the most abundant species. Even near the orbit of Titan, other species are less abundant than protons and the water group species, indicating that the rings and icy satellites are a more significant source of plasma than Titan. We will also describe the abundance and distribution of the minor species, and discuss the implications for their sources within Saturn's magnetosphere.
DE: 2730 Magnetosphere: inner
DE: 2731 Magnetosphere: outer
DE: 2732 Magnetosphere interactions with satellites and rings
DE: 5737 Magnetospheres (2756)
SC: Planetary Sciences [P]
MN: Fall Meeting 2005