HYPERS simulations of solar wind interactions with the Earth's magnetosphere and the moon

Abstract Hybrid simulations, where ions are treated kinetically and electrons as a fluid, seek to describe ion microphysics with maximum physical fidelity. The hybrid approach addresses the fundamental need for space plasma models to incorporate physics beyond magnetohydrodynamics. Global hybrid simulations must account for a wide range of both kinetic ion and whistler/Alfven wave spatio-temporal scales in strongly inhomogeneous plasmas. We present results from two three-dimensional hybrid simulations performed with a novel asynchronous code, HYPERS designed to overcome computational bottlenecks that typically arise in such multiscale simulations. First, we demonstrate an excellent match between simulated lunar wake profiles and observations. We also compare our results to similar ones from two other hybrid simulations performed with conventional (time-stepped) codes. Second, we investigate the interaction of the solar wind with the Earth's dayside magnetosphere under conditions when the orientation of the interplanetary magnetic field is quasi-radial. In this high-resolution simulation we highlight three-dimensional properties of foreshock perturbations formed by the backstreaming ions.