The Space Shuttle Columbia, with its primary scientific cargo known as the U.S. Microgravity Payload-4, lifted off on time at 1:46 p.m. CST Wednesday, to begin a 16-day flight. The primary scientific goals are to investigate materials used by industry, the phenomena of combustion and fundamental physics -- studies important to the future of the nation’s high-technology economy.
The space research will not only add to America’s storehouse of scientific and technical knowledge, but will improve the quality of life on Earth long after Columbia returns. The studies may help produce better semiconductors for complex computers and other high-tech electronics. Stronger metal alloys needed by aircraft and automobile industries to give them an economically competitive edge may result from science research on this mission. Also, research into the unwanted extinction of flames is aimed at making possible better engines for commercial and military jets and improved air safety for all.
After settling comfortably into Earth orbit Wednesday afternoon, the crew of Columbia proceeded with on-orbit activities, including activating the USMP scientific systems. Four hours into the flight, Mission Specialist Winston E. Scott activated two experiment facilities that will study materials in space.
In one facility, an investigation will look at a behavior that may be applicable to materials used in electronic products, such as computer chips. These products contain materials that transmit electrical impulses and absorb heat. As these parts become smaller and thinner, their properties change, often resulting in defects to the parts. Researchers, led by Dr. John Lipa of Stanford University in Stanford, Calif., want to understand what happens to cause changes in properties as parts become smaller or thinner. On Earth, measurements are affected by gravity’s pressure, especially as the surfaces get closer together. In the microgravity of space, the properties spread evenly. Researchers will use liquid helium -- which conducts heat 1,000 times more efficiently than any other material -- to take precise measurements of changes in material properties. Understanding how making electronic parts smaller affects the properties of constituent materials should help researchers find ways to reduce defects and improve electronic products on Earth. Early Thursday, Rick Bevan of Stanford University at Stanford, Calif., who is mission operations manager for the study, said its “activation has been successful, and we are beginning our experiment sequence. Everything is going as well as we hoped at this time.”
The other experiment facility activated by Scott will grow dendritic crystals -- structures which resemble tiny pine trees. Materials will be melted and resolidified to study dendrite formation. Virtually all metal alloys form dendrites when they crystallize. As they grow, the dendrites interlock to form tough materials for use in automobiles, jet engines and even aluminum foil. On Earth, gravity interferes with dendrite crystal formation, creating a flow or movement -- called convection -- in the material as it crystallizes. These flows distort dendrites as they form. But dendrite crystals grown in the low-gravity of space reveal new information about dendrite formation that can be compared with dendrites grown on Earth. Researchers expect this study will lead to improved strength and durability of metals and metal alloys. An investigator participating in the study, Matthew Koss, a research assistant professor at Rensselaer Polytechnic Institute at Troy, N.Y., said early Thursday, “The instrument and growth chamber are working beautifully. We’ve already completed one growth cycle, and actually have new data that will be useful for assessing dendritic growth models.”
Also late Wednesday afternoon, Mission Specialist Dr. Kalpana Chawla activated two experiments in different furnaces designed for growing crystals in microgravity. One is the Advanced Automated Directional Solidification Furnace, and the other is Materials for the Study of Interesting Phenomena of Solidification on Earth and in Orbit -- a joint experiment between NASA and the French Space Agency. Both experiments use precise temperature control to let crystals grow gradually. Without the disturbing effects of Earth’s gravity, large, nearly perfect crystals can be grown. Crystals being grown for these studies are of different types of semiconductor materials used for infrared detectors in weather satellites, burglar alarms and lasers. This research may lead to better crystals for electronic applications and better metal alloys for a variety of products on Earth.
Mission Specialists Chawla and Dr. Takao Doi conducted a checkout of the Microgravity Glovebox late Wednesday afternoon -- a versatile facility to be used by the crew to conduct two materials science investigations and one combustion science experiment during the mission. The glovebox, located in the Shuttle middeck, enables crew members to handle, transfer and manipulate experiment hardware and materials that are not approved for use in the open cabin environment.
The crew began an eight-hour sleep period at 12:46 a.m. CST Thursday. They are to be awakened at 8:46 a.m. CST Thursday to begin the second day of their mission.
USMP-4 mission planners “are making adjustments to the science experiment schedule to accommodate a change in the deployment of the Spartan carrier,” Mission Manager Sherwood Anderson said early Thursday morning. “We anticipate no problems achieving our planned science goals,” Anderson added. Changes in the schedule primarily result in moving activities one day early to Thursday for the Wetting Characteristics of Immiscibles experiment in the Microgravity Glovebox, as well as rescheduling several tests to Thursday in the Confined Helium Experiment.
During the 24 hours ahead, the first test runs will be conducted in an experiment that looks at how to create a uniform mixture of the liquids that form certain metal alloys -- such as those used in bearings or superconductors. Growth of dendrite crystals will continue in a study to make better metals and alloys. Also, a sample will be processed in an onboard furnace to understand how gravity-driven convection affects production of metals, alloys and electronic materials.
The next scheduled Public Affairs status report will be issued at approximately 7 a.m., Friday, Nov. 21. For more information call the Spacelab Newscenter at Marshall Space Flight Center at (205) 544-0034 or visit the web sites: For USMP-4 payload and science information: http://liftoff.msfc.nasa.gov/shuttle/usmp4/ For STS-87 information: http://www.shuttle.nasa.gov
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