Statistical analysis of magnetopause crossings at lunar distances

Abstract

Different magnetopause models with a diverse level of complexity are in use. One thing that they have in common is that they are mainly based on near-earth observations; i.e. they use measurements at distances of about ±10 Earth radii along the GSM x axis. Only very few observations of magnetopause crossings at larger distances are used for model fitting. In this study we compare position and normal direction predictions of the Shue et al. (1997) magnetopause model with actual observations of magnetopause crossings identified using the ARTEMIS spacecraft at lunar distance, about 60 Earth radii. We find differences in the location prediction between model and actual observation but good agreement in predictions about the magnetopause normal direction.