Abstract
In-situ measurements of the Martian ionosphere by the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft revealed that dominant ionospheric ions and thermal electrons sometimes undergo sudden depletions accompanied by an increase in the plasma temperature, known as Plasma Depletion Events (PDEs). In this study, we attempt to identify PDEs simultaneously from local and remote measurements of the MAVEN and Mars Express spacecraft, respectively.
Considering the time durations and spatial extents of PDEs observed by MAVEN and the trajectories of the two spacecraft, we identified 6 out of the 1177 known MAVEN PDEs as possible candidates to be also observed by Mars Express. Using the local plasma density measurements of MAVEN, plausible model ionograms comprising the depleted ionospheric structure have been calculated for different Mars Express altitudes.
We show that the detection of PDEs is feasible by the Mars Express radar sounding for structures with plasma frequencies above about 0.5 MHz.