On the Dipolarization Front and Magnetopause: 1. Comparison and Implications

The dipolarization front (DF), as the leading edge of bursty bulk flows, is typically seen as the boundary between the cold-dense current sheet plasma and the hot-tenuous reconnection outflow plasma. This interface plays an analogous role to the magnetopause, which separates the cold-dense magnetosheath plasma from the hot-tenuous magnetosphere plasma. In this study, we compare the typical characteristics of these two interfaces from the Magnetospheric Multiscale mission observations, revealing several similarities in their plasma environments, ion-scale properties, and kinetic processes. These similarities implicate that some other MHD processes, such as interchange instability, may also develop at the subsolar magnetopause, similar to their occurrence at the leading edge of the DF. Furthermore, the flanks of the DF may be susceptible to Kelvin–Helmholtz instabilities, similar to those observed at the magnetopause flanks. These implications present promising opportunities for further investigation with the upcoming Solar-Wind-Magnetosphere-Ionosphere Link Explorer mission through its global-scale imaging.