For years, the Plant Growth Unit (PGU) was the best plant growth chamber for studying tiny plants in space. Yet, scientists and engineers found numerous ways to upgrade the PGU, enhancing many pieces of equipment while maintaining the same dimensions, and they called this upgraded version the Plant Growth Facility (PGF). This system had a much higher-output lighting system, could accommodate experiment-specific growth media, and was capable of controlling humidity, temperature, and CO2 concentration. Like the PGU, the PGF was a platform for plant reproduction experiments, and it helped demonstrate how ventilation and extra CO2 are needed for seeds to develop normally in space. In 1997 the PGF flew on the shuttle for 15 days to test the effects of microgravity on plant growth for the Collaborative Ukraine Experiment (CUE).

Chamber Components: