Results from the Goddard Space Flight Center's Long Duration Exposure Facility solar array component test

Abstract

A shuttle placed the Long Duration Exposure Facility (LDEF) in space in April 1984 and another shuttle retrieved it in January 1990. The Goddard Space Flight Center supplied a test plate for the LDEF. Conductively coated covers on the test plate demonstrated that they and that several means of connecting to them withstand prolonged exposure to the low Earth orbit (LEO) space environment. Bare solar cells and solar cells with various thicknesses of covers provided data on cell degradation due to hard particle radiation for comparison to ground based predictions. For bare cells, the measured degradation is significantly greater than the predictions. For covered cells, the uncertainty in the measured degradation and the predictions invalidated the comparison. Solar cells covered with fused silica covers having ultraviolet filters and solar cells covered with fused silica covers without ultraviolet filters did not give useful information on the value of the filter.