Ionospheric Plasma Depletions at Mars: MAVEN Observations of In-situ Plasma and Wave properties
- 1Charles University, Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Prague, Czechia (praveen.basuvaraj@matfyz.cuni.cz)
- 2Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
- 3Department of Physics and Astronomy, West Virginia University, Morgantown, WV, USA
Since September 2014, NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has been measuring the in-situ ionospheric constituents of Mars. Recently, MAVEN detected the presence of large-scale plasma depletions (at least ten-fold) within the Martian ionosphere, also known as Plasma Depletion Events (PDEs). Geometrically, the Martian PDEs appear to be bubble-like plasma structures. Although the origin and formation of PDEs are not entirely understood, they are known to occur primarily on the nightside and in regions with stronger crustal magnetic fields.
In this study, we analyze the variation of magnetic field magnitude and direction and electric field power (2–100 Hz) associated with PDEs. We show that, in most cases, the magnetic fields do not considerably change within the plasma-depleted region. Conversely, the low-frequency electric field wave power is enhanced by up to two orders of magnitude at the peak depletion. Both ions and electrons within PDEs are highly magnetized. We present possible formation mechanisms of PDEs supported by recent findings.
How to cite: Basuvaraj, P., Němec, F., Regoli, L., Fowler, C., Němeček, Z., and Šafránková, J.: Ionospheric Plasma Depletions at Mars: MAVEN Observations of In-situ Plasma and Wave properties, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-3122, https://doi.org/10.5194/egusphere-egu23-3122, 2023.
