Ion Outflow from Venus and Mars and the Processes Involved

Abstract:

We review the ion outflow from Venus and Mars. We present the current best estimates of the escaping fluxes and describe the acceleration processes that have been identified. We discuss which solar wind parameters govern the response of the ionosphere as well as the role of the crustal magnetic fields on Mars. Although the characteristics of the two planets are very different, we find both similarities and differences when investigating the ion escape morphology and dynamics. Finally, we compare Venus and Mars with Earth and discuss the effect of a global intrinsic magnetic field on ion outflow and the potential importance of outflowing cold ions.