Lander radioscience for obtaining the rotation and orientation of Mars

Methods and measurements to assess physical and geochemical conditions at the surface of Europa

“…There is no stringent requirement for an additional hardware on the lander. Such measurements effectively complement the satellite gravimetry, as was demonstrated with a much weaker solar tide at Mars using the Pathfinder lander (Yoder et al, 2003; see also Dehant et al, 2009).…”

The radioscience LaRa instrument onboard ExoMars 2020 to investigate the rotation and interior of mars

“…The LaRa experiment is a legacy of the NEtlander Ionosphere and Geodesy Experiment (NEIGE) (Barriot et al, 2001;Dehant et al, 2004). The design has changed from a threeway link lander-orbiter/orbiter-Earth to a direct-to-Earth (DTE) two-way link, and has been proposed to many missions (Harri et al, 1999;Lognonné et al, 2000;Dehant et al, 2009a;. At that time, we were planning to use two frequencies, UHF (Ultra High Frequency) and X-band.…”

Rotation of the Terrestrial Planets

“…Because the older Viking data are an order of magnitude less precise than modern X-band tracking data and the rotation estimates based on them and on Mars Pathfinder data are of comparable accuracy to those based on the modern spacecraft data, an order of magnitude improvement can be expected. Direct two-way range and X-band Doppler measurements between an Earth tracking station and a lander on Mars, or Earth-based radio-tracking observations of an orbiter that is itself tracking one or more landers, would enable the determination of the rotation variations with an accuracy of a few mas (Barriot et al, 2001;Dehant et al, 2009Dehant et al, , 2011Folkner et al, 1997b;Le Maistre et al, 2012;Yseboodt et al, 2003).…”