As of 2009 November 14, AO-7 will have been in orbit for 35 years. Thesatellite continues to provide linear transponder-based communication service tolicensed amateur radio operators worldwide. Spare non-flight photovoltaic solarpanels from the National Aeronautics and Space Administration OrbitingGeophysical Observatory program formed the basis for the construction of theAO-7 solar power system. This paper will present information concerning theorigins, construction, and related performance details of the solar array.Evaluation of a standard radiation degradation model gives a 33% loss formaximum power, a 15% loss for maximum power voltage, and a 23% loss insolar array current output after 35 years of exposure in its radiation environment.Valid telemetry for the electrical current outputs from the four solar panel facetswere received and decoded by several amateur radio service stations during2009 March. The telemetry was of good enough quality in several instances toallow determination of the radiometer-based spin (roll) rates. On 2009 March 3the rate was 0.078 revolutions per minute (12.8 minute period) and on 2009March 16 it was 0.106 revolutions per minute (9.4 minute period). Four AO-7solar array facet output DC electric currents reported in the 2009 telemetry werecompared to the full radiation aged solar array and spacecraft attitude model.The O-C residuals appear to have some periodic structure but in general theaged solar array current output model fits fairly well.
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