HR: 14:25h
AN: P33A-04    [Abstracts]
TI: Preliminary Interpretation of Titan Plasma Interaction as Observed by the Cassini Plasma Spectrometer: Comparisons With Voyager 1
AU: * Hartle, R E
EM: Richard.E.Hartle@nasa.gov
AF: NASA Goddard Space Flight Center, Code 910, Greenbelt Road, Greenbelt, MD 20771 United States
AU: Sittler, E C
EM: edward.c.sittler@nasa.gov
AF: NASA Goddard Space Flight Center, Code 910, Greenbelt Road, Greenbelt, MD 20771 United States
AU: Johnson, R E
EM: rej@unix.mail.virginia.edu
AF: University of Virginia, Engineering Physics, Thornton Hall, Charlottesville, VA 22904 United States
AU: Simpson, D G
EM: David.G.Simpson@nasa.gov
AF: NASA Goddard Space Flight Center, Code 910, Greenbelt Road, Greenbelt, MD 20771 United States
AU: Smith, H T
EM: hts4f@virginia.edu
AF: University of Virginia, Engineering Physics, Thornton Hall, Charlottesville, VA 22904 United States
AU: Crary, F
EM: fcrary@swri.edu
AF: Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78228-0510 United States
AU: McComas, D J
EM: dmccomas@swri.edu
AF: Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78228-0510 United States
AU: Young, D T
EM: dyoung@swri.edu
AF: Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78228-0510 United States
AU: Coates, A J
EM: ajc@mssl.ucl.ac.uk
AF: Mullard Space Flight Center, Holmbury St. Mary, Dorking, Surrey, RH5 6NT United Kingdom
AU: Neubauer, F M
EM: neubauer@geo.Uni-Koeln.DE
AF: University of Koln Institute for Geophysics and Meteorology, Albertus-Magnus-Platz, Koln, D 50923 Germany
AU: Bolton, S
EM: Scott.J.Bolton@jpl.nasa.gov
AF: Jet Propulsion Laboratory, MS 230-205, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Reisenfeld, D
EM: dan.reisenfeld@umontana.edu
AF: University of Montana Department of Physics & Astronomy, 32 Campus Drive, Missoula, MT 59812 United States
AU: Szego, K
EM: szego@rmki.kfki.hu
AF: KFKI-RMKI, KFKI Research Institute for Particle and Nuclear Physics, Konkoly Thege str. 29-33, Bldg. III, Budapest, H-1525 Hungary
AU: Berthelier, J
EM: jacques.berthelier@cetp.ipsl.fr
AF: Centre d'etude des Environnements Terrestre et Planetaires, Observatoire de Saint-Maur, 4 Avenue de Neptune, St. maur-des-Fosses, 94107 France
AU: Michael, M
EM: mm2eq@virginia.edu
AF: University of Virginia, Engineering Physics, Thornton Hall, Charlottesville, VA 22904 United States
AU: Rymer, A
EM: amr@mssl.ucl.ac.uk
AF: Mullard Space Flight Center, Holmbury St. Mary, Dorking, Surrey, RH5 6NT United Kingdom
AU: Vippola, J
EM: jari.vilppola@oulu.fi
AF: University of Oulu, Department of Physical Sciences, Linnanmaa, FIN-90014 Finland
AU: Steinberg, J T
EM: jsteinberg@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Science Group, MS: D-466, Los Alamos, NM 87545 United States
AU: Andre, N
EM: Nicolas.Andre@cesr.fr
AF: CESR, 9, avenue du Colonel Roche, Toulous, 4346 31028 France
AB: The Cassini Plasma Spectrometer (CAPS) instrument made measurements of Titan's plasma environment when the Cassini Orbiter flew through the moon's plasma wake October 26, 2004 (flyby TA) and December 13, 2004 (flyby TB). Preliminary CAPS ion and electron measurements from these encounters (1, 2) are compared with measurements made by the Voyager I Plasma Science Instrument (PLS). The comparisons are used to evaluate previous interpretations and predictions of the Titan plasma environment that have been made using PLS measurements (3, 4). The plasma wake trajectories of flybys TA, TB and Voyager 1are similar because they occurred when Titan was near Saturn's local noon. These similarities make possible direct, meaningful comparisons between the various plasma wake measurements. The inquiries stimulated by the previous interpretations and predictions made using PLS data have produced the following results from the CAPS ion measurements: A) The major ambient ion components of Saturn's rotating magnetosphere in the vicinity of Titan are H+, H2+, and O+. B) Finite gyroradius effects are apparent in ambient O+ as the result of its interaction with Titan's atmosphere. C) The principal pickup ions are composed of H+, H2+, CH4+ and N2+. D) There is clear evidence of slowing down of the ambient plasma due to pickup ion mass loading; and, as the "ionopause" is approached, heavier pickup ions such as N2+ become dominant. The similarities and differences between the magnitudes and structures of the electron densities and temperatures along the three flyby trajectories are described. 1. D. T. Young et al. (2004), Eos Trans. AGU, 85(47), Fall Meet. Suppl., Abstract P41B-07. 2. A. J. Coates et al. (2004), Eos Trans. AGU, 85(47), Fall Meet. Suppl., Abstract P53A-1451. 3. R. E. Hartle et al., J. Geophys. Res., 87, 1383, 1982. 4. E. C. Sittler et al., Titan Symposium Proceedings, ESTEC, Editor, Jean-Pierre Lebreton, 2004.
DE: 5719 Interactions with particles and fields
DE: 5749 Origin and evolution
DE: 5780 Tori and exospheres
DE: 6050 Plasma and MHD instabilities
DE: 6280 Saturnian satellites
SC: Planetary Sciences [P]
MN: 2005 Joint Assembly