Upper atmosphere as seen by Atmospheric Chemistry Suite onboard ExoMars Trace Gas Orbiter

Oleg Korablev (1, 2) , Denis Belyaev (1) , Anna Fedorova (1) , Alexander Trokhimovskiy (1) , Franck Montmessin (3) , Alexey Shakun (1) , Juan Alday (4) , Ekaterina Starichenko (1, 2)

1 IKI - Space Research Institute of the Russian Academy of Sciences
2 MIPT - Moscow Institute of Physics and Technology [Moscow]
3 PLANETO - LATMOS
4 Department of Physics [Oxford]

The ACS instrument onboard the ExoMars TGO dedicated atmospheric spacecraft has been successfully operating since March 2018, delivering unique new data. The processes of water dissipation and the boundary where the lower atmosphere interacts with the exosphere were explored. We will report a selection of results obtained from ACS solar occultations, emphasising the upper part of profiles probing the limits of the neutral atmosphere. The atmospheric profiles were obtained from the strongest CO2 bands up to 200 km altitude. The homopause altitude variation with season was studied. Gravity waves were detected and quantified. Also, the vertical distribution of atmospheric water vapour was measured up to 120 km, resulting in, combined with the altitude profiles of hydrogen and oxygen isotope ratios in CO2 and H2O, implications on the escape of hydrogen from Mars.

Domaines: Planète et Univers [physics]

Oleg Korablev, Denis Belyaev, Anna Fedorova, Alexander Trokhimovskiy, Franck Montmessin, et al.. Upper atmosphere as seen by Atmospheric Chemistry Suite onboard ExoMars Trace Gas Orbiter. 44th COSPAR Scientific Assembly, Jul 2022, Athens, Greece. ⟨insu-03774462⟩