An Analytic Model of Multi-Dimensional Spacecraft Charging Fields and Potentials

This paper presents a relatively simple analytical model describing the spacecraft charging process for multi-dimensional geometries. It is shown that competing monopole and dipole terms in the potential result in a saddle point in the potential on the side of a structure illuminated by the sun. This saddle point is shown to inhibit UV-generated photoemission. The solar illuminated surface is thus not kept at zero potential. These analytic calculations support previous numerical studies.