HR: 0830h
AN: G41B-0035    [PDF]
TI: Interior Models and Gravity Field of Jupiter's Moon Amalthea
AU: Weinwurm, G
EM: gweinw@luna.tuwien.ac.at
AF: Institute of Geodesy and Geophysics, Gusshausstrasse 27-29, Vienna, A-1040 Austria
AU: * Weber, R
EM: rweber@luna.tuwien.ac.at
AF: Institute of Geodesy and Geophysics, Gusshausstrasse 27-29, Vienna, A-1040 Austria
AB: Before its final plunge into Jupiter in September 2003, GALILEO made a last visit to Jupiters moon Amalthea. This final flyby of the spacecrafts successful mission occurred on November 5, 2002. In order to analyse the spacecraft data with respect to Amaltheas gravity field, interior models of the moon had to be provided. The method used for this approach is based on the numerical integration of infinitesimal volume elements, which are calculated by the scale factors of a three-axial ellipsoid (elliptic coordinates). To derive the gravity field coefficients of the body, the second method of Neumann was applied. Based on the spacecraft trajectory data provided by the Jet Propulsion Laboratory, GALILEOs velocity perturbations at closest approach could be calculated. We have derived the harmonic coefficients of Amaltheas gravity field up to degree and order six, for both homogeneous and reasonable heterogeneous cases. Based on these numbers we calculated the impact on the trajectory of GALILEO and compared it to existing Doppler data. Although no two-way Doppler-data was available during the flyby and the harmonic coefficients of the gravity field are buried in the one-way Doppler-noise, the calculated gravity field models of Amalthea can be a basis for further exploration of the Jupiter system. Furthermore, the model approach can be used for any planetary body.
DE: 1241 Satellite orbits
DE: 5417 Gravitational fields (1227)
DE: 6218 Jovian satellites
SC: Geodesy [G]
MN: 2003 Fall Meeting