TacSat-4 Solar Cell Experiment: Two Years in Orbit

The TacSat-4 spacecraft flies in a highly elliptical, 4-hour orbit, passing through proton and electron radiation belts 12 times per day. The TacSat-4 Solar Cell Experiment (TSCE) measures I-V curves on two, 3-cell strings of triple-junction cells, in flat-plate and concentrator configurations. Two additional triple-junction cells are measured at short circuit, testing a replacement cover glass technology. This paper reports on the first two years of experiment operations.