HR: 0800h
AN: P51A-1401    [Abstracts]
TI: Titan's Interaction With the Saturnian Magnetospheric Plasma - Results From an Advanced 3D MHD Model and Comparison With Cassini MAG Data.
AU: * Backes, H
EM: backes@geo.uni-koeln.de
AF: Institut f\"ur Geophysik u. Meteorologie, Universit\"at zu K\"oln, Albertus-Magnus-Platz, Cologne, 50923 Germany
AU: Neubauer, F M
EM: neubauer@geo.uni-koeln.de
AF: Institut f\"ur Geophysik u. Meteorologie, Universit\"at zu K\"oln, Albertus-Magnus-Platz, Cologne, 50923 Germany
AU: Dougherty, M K
EM: m.dougherty@imperial.ac.uk
AF: Department of Physics, Imperial College London, Blackett Laboratory, Prince Consort Road, London, SW7 2BW United Kingdom
AB: We have developed an advanced 3D model for Titan's interaction with the Saturnian magnetospheric plasma. The ideal magnetohydrodynamic (MHD) equations are extended in order to account for the effect of Titan's dense neutral atmosphere has on the plasma interaction. The ion-neutral friction plays a key role in the deceleration of the magnetospheric plasma. From the neutral atmosphere the ionosphere is created within the model by applying a 3D radiation model for the solar EUV radiation. Impact ionization rates by photoelectrons are calculated effectively. In order to account for the process of impact ionization by magnetospheric electrons we have developed a time dependent flux tube model which accounts for flux tube motion through the atmosphere and electron heat conduction along the magnetic field lines. On Titan's nightside magnetospheric electron impact ionization is the only source for ion production. Thus, we obtain a 3D ionosphere that depends on the Saturnian local time (SLT) and the subsolar latitude (SSL). As a reference for the incident magnetospheric plasma parameters we use the parameters measured by Voyager 1. On the 26th of October the first close Cassini flyby at Titan occurs. We have applied our model to the nominal situation at the time of TA, i.e. SLT=10.6 and SSL=-23.2ø. It is most likely that Titan is inside of the Saturnian magnetosphere during the flyby. In that case we will compare the results from our model with the Cassini MAG data along the trajectory and discuss the results.
DE: 6280 Saturnian satellites
DE: 2409 Current systems (2708)
DE: 2732 Magnetosphere interactions with satellites and rings
DE: 2736 Magnetosphere/ionosphere interactions
DE: 2753 Numerical modeling
SC: Planetary Sciences [P]
MN: 2004 AGU Fall Meeting