HR: 17:30h
AN: P44A-07 INVITED     [Abstracts]
TI: Cassini Magnetic Field Measurements and Saturn's Interior
AU: * Smith, E J
EM: edward.j.smith@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AU: Dougherty, M K
EM: m.dougherty@imperial.ac.uk
AF: Imperial College, Prince Consort Rd., London, SW7 2BZ United Kingdom
AU: Giampieri, G
EM: g.giampieri@imperial.ac.uk
AF: Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AU: Giampieri, G
EM: g.giampieri@imperial.ac.uk
AF: Imperial College, Prince Consort Rd., London, SW7 2BZ United Kingdom
AB: Cassini measurements at Saturn Orbit Insertion enable a search for temporal changes in the planetary field, reexamination of a possible departure from axial symmetry and high degree moments all of which could have important implications for the planet's interior. Discovery of a secular variation would be important in testing the hypothesis that the field is decaying away and could provide a means of estimating the depth to the fluid electrically-conducting core in which the field is being generated. The presence of a measurable tilt angle or non- axisymmetric components would test the hypothesis that the field is being shielded by an electrically-conducting shell and provide a determination of the rotation rate of the core. Detecting higher degree source terms than the dipole, quadrupole and octupole moments would enable another approach to estimating the size of the fluid core based on an Earth-like dynamo. These issues are addressed by recent analyses of the Cassini magnetic field observations including subsequent improvements to the spacecraft/ magnetic sensor orientations.
DE: 5724 Interiors (8147)
DE: 5734 Magnetic fields and magnetism
DE: 1510 Dynamo theories
DE: 1560 Time variations--secular and long term
SC: Planetary Sciences [P]
MN: 2004 AGU Fall Meeting