SEAES-GEO: A spacecraft environmental anomalies expert system for geosynchronous orbit

Indications of the space environment hazard at any point in space and time along geosynchronous orbit (GEO) can be obtained using the set of rules described in this paper. These rules are implemented using real-time Geostationary Operational Environmental Satellite particle sensor data and the magnetic index Kp. These rules should be useful for both real-time and posthoc analysis of GEO spacecraft anomalies. The hazards covered are surface charging, internal charging, single-event effects due to solar particle events, and total dose (solar arrays). The system provides a hazard quotient,'' the ratio of the instantaneous to mission-averaged likelihood of an anomaly due to each hazard, based on environmental measurements. With the exception of total dose, the hazard quotients are derived from lists of on-orbit anomalies or their proxies, and it is assumed that the probability of future anomalies will share the same functional dependence on the environment exhibited by the anomalies in the lists. Hazard quotients are potentially more valuable to satellite operators than are raw measurements, as hazard quotients directly convey the statistical relationship between the radiation environment and the likelihood of an anomaly.