Premium
Joint estimation of Martian 20 and rotation variations from simultaneous geodetic measurements: Numerical simulations of a Network Science Experiment
Author(s) -
Duron J.,
Rosenblatt P.,
Yseboodt M.,
Karatekin O.,
Dehant V.,
VanHoolst T.,
Barriot J.P.
Publication year - 2003
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2003gl018353
Subject(s) - orbiter , martian , rotation (mathematics) , geodetic datum , geodesy , mars exploration program , a priori and a posteriori , earth's rotation , geology , computer science , physics , astrobiology , philosophy , epistemology , astronomy , artificial intelligence
The Martian global‐scale CO 2 seasonal cycle implies temporal variations in both the zonal gravity coefficients, such as 20 , and in the rotation rate. To estimate the ability to detect simultaneously these two main geodetic signatures, a new approach based on a Network Science Experiment is investigated. We have numerically simulated the two types of Doppler signals involved, accurate orbiter tracking from the Earth and Martian lander tracking from the orbiter, by using a model of both the rotation variations and the seasonal variations of 20 . Then, through a least square process, we have jointly adjusted the rotation and 20 parameters from an a priori knowledge. Our results show that it is possible to decorrelate 20 from all rotation parameters. We obtain an accurate adjustment of the 20 variations and a precision at the level of a few milliarcseconds for the estimation of the rotation rate variations.