An Assessment of Space Environmental Conditions During the Recent Anik E1 Spacecraft Operational Failure

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A serious operational failure occurred onboard the Anik E1 spacecraft at geostationary orbit on 26 March 1996 at 2047 UT. The satellite lost half of its solar power panels, thereby causing a reduction by about two-thirds of its communication throughput capacity. In this report we discuss other known operational problems of spacecraft at, or near, geostationary orbit at about the same time as the Anik problem. We also show data from the CANOPUS ground-based array as well as solar, solar wind, and magnetospheric satellites in order to assess environmental conditions that might have played a role in the identified anomalies. We conclude that the high-energy (E>~ 1 MeV) electron flux in the outer magnetosphere was greatly elevated compared to normal, quiescent conditions. The amplitude and the duration (~2 weeks) of relatively high electron fluxes suggests that spacecraft deep-dielectric charging could have played a role in causing, or exacerbating, the Anik E1 problem.


National Aeronautics and Space Administration

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