HR: 0830h
AN: G41B-0038    [PDF]
TI: Mars Rotational Parameters from Lander-Orbiter and Lander-Earth Radio-Links
AU: * Yseboodt, M
EM: m.yseboodt@oma.be
AF: Royal Observatory of Belgium, 3 Av. Circulaire, Brussel, 1180 Belgium
AU: Barriot, J
EM: Jean-Pierre.Barriot@cnes.fr
AF: Observatoire Midi-Pyrenees, UMR 5562/GRGS, 14 Av. E. Belin, Toulouse, 31400 France
AU: Dehant, V
EM: v.dehant@oma.be
AF: Royal Observatory of Belgium, 3 Av. Circulaire, Brussel, 1180 Belgium
AU: Rosenblatt, P
EM: Pascal.Rosenblatt@oma.be
AF: Royal Observatory of Belgium, 3 Av. Circulaire, Brussel, 1180 Belgium
AB: With an analytical formulation, we model a Martian Lander-Earth radio link, such as Viking or Pathfinder radio data, and a Martian Lander-Orbiter Radio-Link, as approximation of the future NEIGE (NEtlander Ionosphere and Geodesy Experiment) data. We construct both Doppler and Range observables. These observables have been expressed as a function of time, of the configuration parameters like stations positions or orbit elements, and of Mars' orientation parameters i.e. precession rate, nutations, length-of-day variations and polar motion. We compare the signatures of these rotational parameters on the observables. The temporal decreases of the a posteriori uncertainties on each parameter, as well as the correlations between them are also studied. The difference in the uncertainties when using the Lander-Orbiter and Lander-Earth links are mainly due to the geometry of the configuration and to the distance between the transmitter and the observer for the Doppler observables. We particularly investigate the associated uncertainties on the internal structure of Mars, like inertia moment deduced from precession rate, core and inner-core state and radius from nutations.
DE: 1227 Planetary geodesy and gravity (5420, 5714, 6019)
DE: 5430 Interiors (8147)
DE: 5450 Orbital and rotational dynamics
SC: Geodesy [G]
MN: 2003 Fall Meeting