Design Control Techniques and Developing Issues Relating to Plasma Induced Spacecraft Charging Effects

The initial evidence for the correlation of spacecraft operational and functional malfunctions with geomagnetic substorm activity was obtained from in-flight data of the ATS-5 and ATS-6 geosynchronous spacecraft launched in 1969 and 1974 respectively (Reference 1). The spacecraft charging technology has evolved in response to the need to understand and control the spacecraft functional and operational irregularities associated with charging and discharging in the plasma environment. From the technology, design control techniques have developed and been refined as the physical understanding of the charging mechanisms, in Geosynchronous Orbit (CEO), Low Earth Orbit (LE) and Polar Earth Orbit (PEO) environments has matured. Developing issues motivating proposed research efforts include the capability to predict effects on spacecraft of arc discharges resulting from plasma induced charging, the improvement of current spacecraft charging design countermeasures, and the achievement of a more lucid understanding of plasma induced spacecraft charging mechanisms, as for example, those resulting in power losses for higher power source systems.