Earth Planets Space, Vol. 64 (No. 2), pp. 165-178, 2012
Stephen H. Brecht1 and Stephen A. Ledvina2
1Bay Area Research Corp., P.O. Box 366, Orinda, CA 94563, USA
2Space Sciences Laboratory, UC Berkeley, 7 Gauss Way, Berkeley, CA, USA
(Received February 10, 2011; Revised May 14, 2011; Accepted May 30, 2011; Online published March 8, 2012)
A hybrid particle code has been used to examine the interaction of the solar wind with Mars during solar minimum. The results were surprising as they produced ion loss rates from Mars far in excess of what is estimated from MEX. The results are analyzed and found to be consistent with the competition between photochemical rates and advection of the ionosphere. The simulations showed significant erosion of the ionosphere at altitudes between 200 km and 250 km altitudes. Addition of the crustal magnetic fields reduced the erosion and reduced the ion loss rates to a level consistent with the data.
Key words: Mars, ionospheric loss, crustal magnetic fields, simulation, solar wind interactions.