A close-up view of the simulated magnetospheric configuration for the Highly Compressed Magnetosphere (HCM) event observed by MESSEGER on 23 November 2011. (a) Color contours of the z-component of the magnetic field perturbation (B_1z in nT) shown in the XZ plane and also on a 3D sphere of radius ~0.8 R_M corresponding to the core-mantle boundary. (b) Same as (a) but for the current density in the y-direction (J_y in nA/m²), indicating enhanced magnetopause and tail currents as well as the induction currents at the core in response to solar wind compression. In both panels, the black lines with arrows show projections of sampled magnetic field lines onto the XZ plane and the magenta lines with arrows show sampled streamlines of the induction currents generated at the core. The green circle of radius 1 R_M represents the planetary surface (from Jia et al., 2019).