Assessing how BepiColombo will use Solar Wind Variability to Probe Mercury's Interior

The interaction of the solar wind and embedded interplanetary magnetic field with Mercury's magnetosphere drives an electric current on the magnetopause boundary. The variability of the external solar wind forcing causes motion of the magnetopause and changes of the current structure on this boundary, and the resulting inductive processes may be exploited to determine the interior structure of magnetized planets. In preparation for the arrival of the BepiColombo spacecraft at Mercury, we here assess different contributors of solar wind forcing in this planet's environment, through analysis of magnetic field and plasma data acquired by the Helios spacecraft, and their impacts on the inducing field of the magnetopause. These measurements suggest that the solar wind conditions at Mercury are highly unpredictable and that the inducing field generated in response to the variable solar wind dynamic pressure is non-uniform across the planet's surface. The inducing magnetic field spectrum suggests that the transfer functions derived from the two BepiColombo spacecraft could allow us to obtain a profile of conductivity through Mercury's crust and mantle.