Radar blackouts in Mars' atmosphere produced by space weather events during the life time of Mars Express and Mars Reconnaissance Orbiter
Résumé
The Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) onboard Mars Express (MEX) and the Shallow Radar (SHARAD) onboard Mars Reconnaissance Orbiter (MRO) suffer from severe degradation in the ground reflection signal almost every time a solar energetic particle (SEP) event strikes Mars. The most notable case occurred in September 2017, when the signals of both radars were completely absent for several days (Figure 1) [1]. The cause was likely the precipitation of SEP electrons of a few tens of keV that are believed to produce a lower ionospheric layer within the collision-dominated atmosphere which can absorb the radar signals. In this study, we go one step further and evaluate when and under which conditions this absorption layer appears and its main properties for the lifetime of both the MEX and MRO missions.
Domaines
Planète et Univers [physics]Origine | Fichiers produits par l'(les) auteur(s) |
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