Copy right The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. Model calculati

Based on a recent model of the Martian atmosphere/exosphere and a model of the magnetic field and solar wind flow around Mars, the distribution of different planetary ion species in the near tail is calculated. Three main regions are identified: 1) “clouds ” of pickup ions with distinct mass separation travel along cycloidal trajectories; 2) another group of ions forms a distinct plasma mantle in the magnetosphere; 3) a third population fills up the plasma sheet. Further, the energy of ions in different locations is also analyzed. Finally, comparison of observations made onboard the Phobos-2 spacecraft shows a reasonable agreement with simulation results. 1