The first United States Microgravity Laboratory (USML-1) was one of NASA's science and technology programs that provided scientists an opportunity to research various scientific investigations in a weightless environment inside the Spacelab module. It also provided demonstrations of new equipment to help prepare for advanced microgravity research and processing aboard the Space Station. The USML-1 flew in orbit for extended periods, providing greater opportunities for research in materials science, fluid dynamics, biotechnology (crystal growth), and combustion science. This is a close-up view of the Astroculture experiment rack in the middeck of the orbiter. The Astroculture experiment was to evaluate and find effective ways to supply nutrient solutions for optimizing plant growth and avoid releasing solutions into the crew quarters in microgravity. Since fluids behave differently in microgravity, plant watering systems that operate well on Earth do not function effectively in space. Plants can reduce the costs of providing food, oxygen, and pure water, as well as lower the costs of removing carbon dioxide in human space habitats. The USML-1 flew aboard the STS-50 mission on June 1992 and was managed by the Marshall Space Flight Center.