Abstract When the interplanetary magnetic field (IMF) changes toward its final orientation, induction within the Moon enhances the magnetic field beneath the lunar surface but outside the conductive interior. This enhanced magnetic field compresses the solar wind near the lunar terminator, forming limb compression structures. Using three-dimensional, time-dependent magnetohydrodynamic (MHD) simulations, we systematically explore how the lunar core radius, core conductivity, and the amplitude of the IMF variation influence these limb compression structures. Our findings demonstrate that a larger core radius, higher core conductivity, and a larger magnetic field change result in a stronger induced magnetic field and more pronounced limb compression. However, when core conductivity exceeds 0.1 S m−1, further increases in the core conductivity have minimal impact. These simulation results serve as a forward-modeling study that lays the groundwork for future efforts to constrain the lunar interior stratification under conditions of external magnetic field perturbations by combining numerical modeling with spacecraft observations.
Yi et al. (Wed,) studied this question.