Neutral particle environment of Mars: The exosphere-plasma interaction effects

Because of the non-existent or very weak intrinsic planetary magnetic field, the solar wind interaction process at Mars is characterized by direct streaming of the solar wind plasma flow through the Martian exosphere. Also as a result of the low gravity at Mars, rather extended distributions of hot oxygen atoms and cold hydrogen atoms could be found even at altitudes of a few thousand km. The ionization and subsequent pickup of such exospheric ions by the interplanetary electric field could have very important consequences on the structure of the bow shock, the injection of planetary heavy ions into the magnetospheric environment, and non-thermal mass loss. The hydrogen component of the exosphere might play a particularly important role in creating a seed population of reflecting ions as well as depleting the solar wind plasma - via charge exchange process - near the magnetopause.