The Earth’s magnetosphere: an introduction

Abstract

Since its discovery shortly after the International Geophysical Year, the terrestrial magnetosphere has been under intensive study with satellites and ground-based instrumentation. We have a fairly good picture of its main structural features and the dynamic behavior of its mUltiple regions. Micro and mesoscale processes have been proposed for the -coupling between these regions, but we do not yet have a global, quantitative description of the mass and energy flows into, through and out of the system, nor do we possess detailed knowledge of the configuration and dynamic behavior of the basic "skeleton" of the magnetosphere, namely the electric current sheets and filaments sustaining the external magnetic field and everything that is tied to it. The present status of Wlderstanding is reviewed in the light of current plans for the magnetospheric components of the International Solar-Terrestrial Energy Program.