Comparison of Coulomb-2, NASCAP-2K, MUSCAT and SPIS codes for geosynchronous spacecraft charging

In the paper, we discuss numerical modeling of spacecraft charging in geosynchronous orbit which was done using Coulomb-2, NASCAP-2K and SPIS codes, and present data obtained using the MUSCAT code too. The main distinctive features of the codes above are specified, description of the Coulomb-2 code is given in more details. We compare the results of calculations obtained for similar models of spacecrafts with identical surface materials and parameters of the space plasma environment. The possible reasons of divergence of the modeling results are discussed.