STS-91 Experiment Summary

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Alpha Magnetic Spectrometer (AMS)
The AMS experiment is the first time a high energy particle magnetic spectrometer is placed in orbit. The space environment provides a copious flux of atomic and subatomic particles which have been naturally accelerated to energies which are impossible to achieve in Earth bond accelerators. The AMS provides the first in-situmagnetic detector of these particles and will open a unique and rich new area of experimental high energy physics. On STS-91, a group of eminent scientists in the field who reviewed AMS for the department unanimously endorsed its scientific merit. Researchers use the detector to search for both antimatter and "dark matter" to answer two specific questions. First, if equal amounts of matter and antimatter were produced at the beginning of the universe as described by the Big Bang scenario, and the galaxies we now see are made only of matter, where has the antimatter gone? Second, since the mass of a galaxy seems to be greater than the visible mass of all its stars, gas and dust, is there dark matter of a new kind that has eluded discovery?

Commercial Protein Crystal Growth (CPCG) Payload
The Commercial Protein Crystal Growth (CPCG) payload is designed to conduct experiments which will supply information on the scientific methods and commercial potential for growing large high-quality protein crystals in microgravity.

Get Away Specials (GAS) Experiments
Several Get Away Special (GAS) payloads were manifested by the Shuttle Small Payloads Project at the Goddard Space Flight Center in Greenbelt, Md. A few of the GAS payloads included:
  • The Atlantic Canada Thin Organic Semiconductors (ACTORS) experiment is sponsored by the Canadian Space Agency's Microgravity Sciences Program. This payload, prepared by the University of Moncton in New Brunswick, processes an important type of semiconductor organic material.
  • The Canadian Space Agency and several partners launched an exciting set of space experiments in search of new ways to extract oil from the Earth and clean up accidental spill in the environment.

Solid Surface Combustion Experiment (SSCE)
The SSCE series of experiments are designed to characterize flame spreading in microgravity and its differences from normal gravity behavior, leading to a better understanding of the physical processes involved. The knowledge gained is expected to enhance our understanding of fire behavior, both in space and on Earth.

Space Experiment Module (SEM)
Each Space Experiment Module contains multiple experiments from middle school, high school and college students around the country. An overview of a couple of these experiments is as follows.

Shoreham (N.Y.) Wading River High School -- The Effect of Microgravity on Crossing-Over in Sordaria Fimicola. The experiment studies the effect of microgravity on the crossover rate (union between strains of a species) of the fungus called Sordaria Fimicola. Genetic cross-over is a form of natural genetic recombination (which is another term for crossovover) without which a species of organisms can experience reduced genetic variability.

Tomasita Young Astronauts Club, Albuquerque, N.M. -- Crystal Growth in Microgravity The purpose of this experiment is to compare the growth of crystals in a microgravity environment to those grown on the ground. Crystals are measured for purity and the structure is examined through the use of a scanning electron microscope located at the University of New Mexico.

Purdue University, West Lafayette, Ind. -- Cosmic Radiation Effects on Programmable Logic Devices (CREPLD) The purpose of this experiment is to determine the effects of cosmic radiation on unshielded Programmable Logic Devices (PLDs). PLDs are integrated circuits which can be programmed to perform many functions.