Preliminary results from the Advanced Photovoltaic Experiment flight test

The Advanced Phototovoltaic Experiment is a space flight test designed to provide reference cell standards for photovoltaic measurements and to investigate the solar spectrum and the effect of the space environment on solar cells. After a flight of 69 months in low earth orbit as part of the Long Duration Exposure Facility set of experiments, it was retrieved in January 1990. The electronic data acquisition system functioned as designed, measuring and recording cell performance data over the first 358 days of flight, limited by battery lifetime. Significant physical changes are also readily apparent, including erosion of front surface paint, micrometeoroid and debris cratering, and contamination.