19. June 2013
IWF Research > Solar System > Planets > Mars > Mars Research > Martian Atmosphere > Atmospheric Escape > Solar Wind Interaction
The main uncertainties between minimum and maximum atmospheric loss are related to present uncertainties of the efficiency of loss rates triggered by plasma instabilities and momentum transfer effects between the solar wind and the ionosphere. We investigated the growth rate for the Kelvin Helmholtz (KH) instability at the Martian ionopause and found that this instability may evolve into a non-linear stage at the whole terminator plane, but preferably at the equatorial flanks (Fig.). Escape rates of O+ ions (~1024 s-1) due to detached plasma clouds implicate that loss by instabilities should be comparable with other loss processes studied by the ASPERA-3 instrument on board of Mars Express.
- Fig.: Instability growth rate for a Martian ionopause altitude of 400 km and a solar wind velocity of 400 km/s at the flanks near the terminator plane.
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