Onboard Space Shuttle Columbia (STS-50) in the United States Microgravity Laboratory (USML-1) mission specialist Ellen S. Baker is hard at work.

Onboard Space Shuttle Columbia (STS-50) payload commander Bornie Dunbar performs life science experiments on crewmember payload specialist Lawrence Delucas in the United States Microgravity Laboratory (USML-1) science module.

Onboard Space Shuttle Columbia (STS-50) all work and no play make commander Richard (Dick) Richards and payload commander Bornie Dunbar take a break from their work in the United States Microgravity Laboratory (USML-1) responsibilities.

Space Shuttle Columbia (STS-50) onboard photo of the United States Microgravity Laboratory (USML-1) module in payload bay in this scene over the southern two-thirds of the Florida peninsula. Kennedy Space Center (KSC) can be seen just above Columbia's starboard wing.

Space Shuttle Columbia (STS-50) onboard photo of astronauts working in United States Microgravity Laboratory (USML-1). USML-1 will fly in orbit for extended periods of time attached to the Shuttle, providing greater opportunities for research in materials science, fluid dynamics, biotechnology, and combustion science. The scientific data gained from the USML-1 missions will constitute a landmark in space science, pioneering investigations into the role of gravity in a wide array of important processes and phenomena. In addition, the missions will also provide much of the experience in performing research in space and in the design of instruments needed for Space Station Freedom and the programs to follow in the 21st Century.

Payload Commander, Bonnie Dunbar working onboard STS-50 USML-1

Payload Commander, Bornie Dunbar loading samples in the CGF onboard STS-50, USML-1.

Payload Commander, Bornie Dunbar activating ZCG autoclave onboard STS-50, USML-1

Onboard Space Shuttle Columbia (STS-50) crewmembers rally around the American flag in the United States Microgravity Laboratory-1 (USML-1). Pictured are (from top, left to right) pilot Kerneth D. Bowersox; payload specialist Lawrence J. Delucas; commander Richard N. Richards; payload commander Bonnie J. Dunbar; mission specialists Carl J. Meade and Ellen S. Baker; and payload specialist Eugene H. Trinh.