Model investigation of current system and influence of the crustal fields on the large scale structure of current sheets at Mars

•Mars has current systems generally of an induced feature, consisting of interconnected tail and MPB currents.•The crustal fields may disorder ionospheric current distribution and pushing the current sheet to higher altitude.•The crustal fields also change the orientation and configuration of the near tail current sheet.

Based on the global MHD simulation, the current system in Martian magnetosphere and the influence of the crustal fields on current distribution in the near mars space are investigated in this paper, results show Mars has current systems generally of an induced feature, consisting of interconnected tail and MPB currents whose orientation is controlled by the clock angle of the interplanetary magnetic field. However, the crustal fields have significant impacts on the ionospheric currents, disordering current distribution and pushing the current sheet to higher altitude. The crustal fields may also change the orientation and configuration of the near tail current sheet, which implies that the near tail current is not purely of an induced feature, but also controlled by the crustal fields to some extent.