For Release: May 16, 1996

Steve Roy
Office of Media Services
(205) 544-0034
steve.roy@msfc.nasa.gov

NOTE TO EDITORS: 96-41N

MARSHALL MATERIALS AND PROTEIN CRYSTAL GROWTH
EXPERIMENTS TO FLY ON STS-77

Researchers are looking to space to markedly improve the speed of next-generation computers and to produce new drugs to combat disease.

They'll move a step closer to those goals next week when the Space Shuttle Endeavour is launched on STS-77, a scheduled 10-day mission, carrying among its cargo two experiments that could one day lead to improved quality of life on Earth.

Scientists have learned from previous missions that crystals grow and behave differently in microgravity. On STS-77, they want to identify why and how they grow differently in space than on Earth.

One of the experiments, known as the Commercial Float Zone Furnace, uses a special heat lamp to melt samples of various materials and form crystals. As the cylindrical-shaped samples are moved past the lamp and cooled, they solidify and in space, form crystals of improved quality.

For one set of furnace experiments, scientists from three international space agencies - the United States, Canada and Germany - are cooperating to grow or process semiconductor and electro-optical crystals in the weightlessness of space.

Computer chips made of gallium arsenide, a synthetic compound semiconducting material grown in the furnace, can perform calculations thousands of times quicker than silicon chips installed in the latest generation of computers. Also, crystals of gallium antimonide grown in the furnace are used in the manufacture of lasers and infrared detectors.

These crystals are the key to making miniaturized integrated circuits, used in products from high-speed computers to cellular phones to sensors and special devices called non-linear optical systems.

Potential payoffs from this experiment could include improved remote sensing, such as satellite monitoring; imagery systems that could be used in medical diagnostics; and specialized measurement methods, such as one required to measure the impact of pollution on the environment.

The Marshall Center is overseeing this international effort, coordinated by Jimmy R. Watkins, projects manager of the Commercial Development and Applications Office. Principal investigator for NASA is Dr. Reza Abbaschian of the University of Florida.

The Commercial Float Zone Furnace used to process material for the experiment was developed as a joint effort by the Canadian Space Agency and the German Space Agency.

Also aboard the next Shuttle is a companion experiment that will expand research of the structure and nature of protein molecules, and could lead to greater understanding of their functions in living organisms.

An important by-product of this research is continued improvement of medicines in the escalating fight against the world's diseases.

The experiment, the Handheld Diffusion Test Cell, is an extension of those conducted aboard previous Shuttle missions that have demonstrated the superior crystal-growing conditions of microgravity in space. The experiment is a small specialized container, which houses protein samples, and when activated by the crew, slowly mixes protein samples to grow better crystals.

On this flight, the experiment has been markedly improved, including a redesign and increase in the number of test cells, better fill ports for removal of bubbles after the test chambers fill, better video imaging of the test, and power-driven activation of the test.

Pharmaceutical company researchers, who found space-grown crystals larger and easier to analyze, hope that knowledge from these experiments will lead to the development of new disease-fighting drugs.

Ron King, a protein crystal growth project manager at of Marshall Center's Science and Applications Project Office, is coordinating the experiment. The principal investigator is Dr. Alexander McPherson Jr. of the University of California-Riverside, in Riverside, Calif.

The test samples developed for the Commercial Float Zone Furnace and the Handheld Diffusion Test Cell experiment are managed by the Marshall Space Flight Center in Huntsville, Ala.

STS-77, is scheduled for launch Sunday, May 19 at 5:30 a.m. CDT, aboard the Space Shuttle Endeavour. Landing is now set at the Kennedy Space Center, Fla., on Wednesday, May 29 at 6:07 a.m. CDT.