Global Hybrid Simulations of Solar Wind Interaction with the Hermean Magnetosphere

Mariner 10 observations suggest the Hermean magnetosphere has a terrestrial-like structure. From the theoretical point of view, until recently, no scaling laws regarding solar wind interaction with magnetic dipoles of various strength existed. As a result, it was not obvious as to whether the Hermean magnetosphere should be earth-like or not. Using global hybrid (kinetic ions, fluid electrons) simulations, we have demonstrated the presence of a spectrum of magnetospheric structures associated with dipoles of various strength. It was found that once the standoff distance of the magnetopause is greater than about 20 solar wind ion skin depth, the resulting magnetosphere is similar to that of the earth. In the case of Mercury, the standoff distance of the magnetopause is about 70-80 local solar wind ion skin depth and accordingly the magnetosphere should be terrestrial-like. Here, we present results from global hybrid simulations of solar wind interaction with the Hermean magnetosphere under a variety of interplanetary magnetic field (IMF) conditions. By virtue of their kinetic nature, these simulations can shed light on micro- and macrophysics of the ion foreshock, the bow shock, magnetosheath, magnetopause, lobe and the plasma sheet. After a brief review of these regions, we concentrate on the low and high latitude magnetopause and comparisons with the Mariner 10 data.