Colloquium: Alfonso Maria Caldiero (Spaceflight)

04 November 2019 12:45 - Location: Lecture room C, Faculty of Aerospace Engineering, Kluyverweg 1, Delft

Expected accuracy of Mars rotation and orientation estimation from TGO orbit determination.

The RISE and LaRa transponders will provide precise measurements of the Mars rotation and orientation parameters (MOP). The MOP are sensitive to the interior properties of Mars, particularly to the presence and size of a liquid core. The improvement of the accuracy of the MOP solution given by the inclusion of radio-tracking data from Trace Gas Orbiter (TGO) was studied in this project.  From a covariance analysis, this improvement is of up to 6% for the Chandler wobble (CW) amplitudes, up to 8% for the length-of-day variations (LOD) amplitudes, and up to 20% and 12% on the nutations amplification factor and the free-core nutation (FCN) frequency (the latter two judged excessively optimistic). No definite inference on the resulting core radius accuracy improvement could be made.The orbits most affected by the MOP were analytically found to be near-circular at 40° inclination for CW, highly-eccentric and near-equatorial for LOD.