Flight Dynamics Operational Experience From Exomars TGO Aerobraking Campaign At Mars

Density Fluctuations in the Lower Thermosphere of Mars Retrieved From the ExoMars Trace Gas Orbiter (TGO) Aerobraking

“…This approach was applied to all processed data presented in this paper. The densities have been calculated from the accelerometer data using the aerodynamic parameters of TGO [1,2]. The above described procedure for acceleration was then applied for evaluating density fluctuations.…”

“…TGO performed an 11-month-long aerobraking campaign between 14 March 2017 and 20 February 2018 to gradually reduce its orbital period from approximately 24 h to 2 h, by passing through the Martian atmosphere 952 times at the pericenters of the initially highly elliptical orbit, thereby accumulating a total drag ∆V of about 1017 m s −1 with a limited propellant usage. An extensive overview of the TGO aerobraking design and operations is given in the paper of Denis et al [1], while Castellini et al [2] elaborated on this challenging campaign from a Flight Dynamics perspective. Our work exploits the fact that TGO reached the denser layers in the thermosphere and the on-board accelerometers registered variations of the atmospheric drag with high temporal and spatial resolution.…”

MaQuIs - Mars Quantum Gravity Mission

“…General Circulation Models (GCMs) and ionosphere-thermosphere models are commonly used to model the atmosphere on large scales, as for example the longitudinal dependence of the atmospheric density and its annual changes. But they fail to capture the short term variations in the Martian upper atmosphere, as has been confirmed during operational aerobreaking maneuvers by many previous space missions from ESA and NASA (e. g. Castellini et al, 2018).…”