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The Martian magnetosphere contains elements of induced and intrinsic origin. To display them one must use different coordinate systems. Although the solar-electric coordinate system (Mars Solar Electric [MSE]) adequately describes the main features of the induced magnetosphere, it removes/suppresses aspects caused by the crustal magnetic sources while rotating the spacecraft position to the MSE-coordinate system and averaging over many orbits. On the other hand, to observe effects of the crustal field one should use the solar orbital coordinates (Mars Solar Orbital [MSO]). To find a compromise and keeping in mind that the most probable value of the clock angle of the interplanetary magnetic field (IMF) on the Mars orbit is ∼90° we can consider separately cases with positive and negative By components of the IMF. It is shown that dynamics of ion fluxes in the distant regions of the magnetosphere is mainly controlled by induced features. However, reconnection of the draping IMF with crustal field leads to a twisting of the classical draping configuration. Despite of the very intricate local geometry of the crustal field, the low-order harmonics of the magnetic field and mainly the dipole component determine the reconnection sites, at least, statistically for many Mars rotations. For different signs of the By component of the IMF these sites occur either in the +Y-MSO or −Y-MSO hemispheres. As a result, statistically the magnetosphere of Mars looks like a hybrid magnetosphere formed during the solar wind interaction with the obstacle which simultaneously contains an extended ionosphere and a weak dipole magnetic field.

Analysis of Mars Atmosphere and Volatile Evolution (MAVEN)/Supra‐Thermal And Thermal Ion Composition observations in the Martian upper atmosphere, bounded at higher altitudes by the shocked solar wind, shows that the draping of interplanetary magnetic field penetrates down to low altitudes (∼200−250 km) and governs dynamics of the ionosphere. The upper ionospheric plasma is driven into motion flowing around Mars similar to the shocked solar wind in the adjacent magnetosheath. Such a fluid‐like motion is accompanied by ion acceleration caused by the bending of the magnetic field, leading to ion extraction and finally to ion pickup. Extraction of ions and their acceleration produces a recoil effect of the bulk ionosphere in the opposite direction. This provides a strong asymmetry in ion dynamics in two different hemispheres, accompanied by wrapping of the magnetic field lines around Mars and respective reconnection., Plain Language Summary: Although the Martian magnetosphere is hybrid and contains components of the induced and intrinsic magnetosphere, is possible to display these components by using the specific coordinate systems. Here we study the properties of the induced magnetosphere using the data obtained by MAVEN spacecraft. The interplanetary magnetic field penetrates deep into the Martian ionosphere draping around Mars and drive to the motion dense ionospheric plasma. Draping features and the induced plasma motions occur different in two hemispheres determined by the direction of the motional electric field in the solar wind. Ion acceleration and extraction is accompanied by a recoil effect that leads to a shift and asymmetry of the ionosphere., Key Points: Draping of the interplanetary magnetic field around Mars penetrates deep to the ionosphere enveloping the planet and driving the ionosphere to the bulk motion. Draping and motion of the ionospheric plasma is characterized by asymmetry by the direction of the motional electric field in solar wind. Ion acceleration and extraction from the ionosphere is accompanied by a shift of the bulk ionosphere in the opposite direction., National Aeronautics and Space Administration http://dx.doi.org/10.13039/100000104, DFG http://dx.doi.org/10.13039/501100001659, Russian Science Foundation http://dx.doi.org/10.13039/501100006769