Payload Specialist Ulf Merbold works on the Gradient Heating Facility on the Materials Science Double Rack (MSDR) inside Spacelab in the Shuttle Orbiter Columbia's payload bay during STS-9/ Spacelab-1. Spacelab-1, the joint ESA/NASA mission, was the first operational flight for Spacelab, and demonstrated new instruments and methods for conducting experiments that are difficult or impossible in ground-based laboratories. This facility performed, in extremely low gravity, a wide variety of materials processing experiments in crystal growth, fluid physics and metallurgy. T