Space Weather and Satellite Anomalies

Results of the Satellite Anomaly Project, which aims to improve the methods of safeguarding satellites in the Earth's magnetosphere from the negative effects of the space environment, are presented. Anomaly data from the "Kosmos" series satellites in the period 1971-1999 are com-bined in one database, together with similar information on other spacecrafts. This database contains, beyond the anomaly information, various characteristics of the space weather: geo-magnetic activity indices (Ap, AE and Dst), fluxes and fluencies of electrons and protons at different energies, high energy cosmic ray variations and other solar, interplanetary and solar wind data. A comparative analysis of the distribution of each of these parameters relative to satellite anomalies was carried out for the total number of anomalies (about 6000 events), and separately for high ( 5000 events) and low (about 800 events) altitude orbit satellites. No relation was found between low and high altitude satellite anomalies. Daily numbers of satel-lite anomalies, averaged by a superposed epoch method around sudden storm commencements and proton event onsets for high (∼1500 km) and low (¡1500 km) altitude orbits revealed a big difference in a behavior. Satellites were divided on several groups according to the orbital char-acteristics (altitude and inclination). The relation of satellite anomalies to the environmental parameters was found to be different for various orbits that should be taken into account under developing of the anomaly frequency models. The preliminary anomaly frequency models are presented. Keywords: Space weather; Satellite anomalies; Energetic particles; Magnetic storms