Post-flight investigation of the ASGA solar cell experiment on EURECA

After eleven months in orbit, at an altitude of 500 km, the European Retrievable Carrier (EURECA) was retrieved by Shuttle Endeavour in June 1993. ASGA, a solar cell test facility, was installed on EURECA to test in-orbit performances of advanced GaAs solar cells and solar panel components. This paper describes the investigations carried out on the solar panels after the flight and critically reviews the telemetry data after post-flight solar cell calibration. Essentially, the physical effects on the hardware, arising from a one-year exposure to a LEO environment, are the degradation of some components consequent to the atomic oxygen erosion and the micrometeoroid impacts. The solar cells (GaAs/Ge, GaAs ultrathin and concentrator cells) have run properly and post-flight calibration confirms a negligible degradation in electric performance