NASA’s Next Space Shuttle Mission Features Space Station and Science Experiments

A new piece of the International Space Station tested at NASA’s Marshall
Space Flight Center in Huntsville, Ala., and new scientific experiments
managed by the Marshall Center are among the payloads for the upcoming
launch of Space Shuttle Atlantis.

“The cargo aboard Shuttle Atlantis is typical of Marshall’s broad
capabilities in space exploration,” Marshall Center Flight Projects Director
Dr. Jan Davis said. “From large structures to research at the microscopic
level, Marshall’s expertise continues to be a critical part of the ongoing
mission of the world’s only research center in space.”

During the upcoming mission Atlantis will deliver the backbone-like S-1
Truss segment to the Space Station. Once attached to the Station, its main
job will be to provide structural support for the orbiting research
facility’s radiator panels, which use ammonia to cool the Station’s complex
power system. The S-1 truss segment also will house communications systems,
attachment points for external experiments and other subsystems.

Primarily built of aluminum, the truss segment is 45 feet long, 15 feet wide
and 10 feet tall. When fully outfitted, it will weigh 31,137 pounds.
Manufactured by the Boeing Company, in Huntington Beach, Cal., the truss
primary structure was transferred to Marshall from February 1999 until
October 1999 for hardware installations and manufacturing acceptance
testing. The S1 Structural Test Article (STA), a full-scale test piece,
which was also manufactured in Huntington Beach, Cal., was outfitted with
hardware installations and test sensors then underwent dynamic testing at
the Marshall Center.

“Boeing shipped the truss to Marshall from California,” said Lanny Upton, a
test engineer at the Marshall Center. “Boeing employees here installed
cabling, fluid lines and other equipment. Then our NASA engineers attached
several hundred sensors to it and subjected it to a variety of strains and
stresses that it will experience in the Shuttle cargo bay during launch and
during its lifetime in space.”

Boeing employees and local contractors built more than 140 wiring harnesses
and welded metal tubing to carry power and fluids for the Station’s cooling
radiator panels. They designed 600 pieces of multi-layer insulation to
shield the S-1 truss from the extreme cold and heat of space. They also
built 34 umbilical mating adapters and 11 video cameras that will be fitted
along the full length of the Station framework by the time it’s completed.
The adapters will serve as plug-ins for spacewalking astronauts’ power
tools, while the cameras will give astronauts inside the Station a
full-length view of the Station’s exterior. Boeing workers also installed a
new antenna on the S-1 truss that will markedly improve communications with
ground controllers.

“This is much more than just a structural component,” said Alex Pest, a
Boeing manager who oversaw the completion of the S-1 truss. “It’s a very
important part of the Station. ”

Testing allowed engineers to prove that the truss as built matched the
strength requirements of the design, as well as verify electrical
connections and fluid line integrity, said Marshall Center test engineer
Alan Patterson. Test engineers used both electromagnetic shakers and
hydraulic cylinders to simulate events such as launch, assembly, Shuttle
docking and other stresses that the truss will have to withstand.
Continuing scientific research of the fifth crew to occupy the Space
Station, Atlantis will carry three new experiments for transfer to the
Station and additional samples for a fourth. Four completed experiments
will be transferred from the Station to the Shuttle for return. The
exchange of scientific experiments represents research in the fields of
medicine, biotechnology, agriculture, petroleum processing and
pharmaceuticals.

Two of the experiments headed to the Space Station involve commercial
research sponsored by private industry through NASA’s Space Product
Development Program at the Marshall Center. A third is fundamental research
managed by the Macromolecular Biotechnology Program at Marshall.
The Commercial Generic Bioprocessing Apparatus (CGBA) will serve as a
refrigerator to stabilize biological samples from the Plant Growth
Bioprocessing Apparatus for post-flight analyses. The Plant Growth
Bioprocessing Apparatus (PGBA) will fly to the Station to investigate the
effects of microgravity on plant structures. Following flights on
Expeditions Two and Four, the Protein Crystal Growth Single-locker Thermal
Enclosure System (PCG-STES) again will provide a temperature-controlled
environment for growing high-quality protein crystals of selected proteins
in microgravity for analysis on the ground. And the Shuttle will bring
fresh Zeolite Crystal Growth (ZCG) samples for processing.

Returning to Earth with Atlantis on this mission are soybean plants grown in
the Advanced Astroculture experiment, PCG-STES protein crystals for
analysis, experimental capsules for drug delivery from the
Microencapsulation Electrostatic Processing experiment, liver cell tissue
samples cultured in the StelSys experiment, and Zeolite Crystal Growth
samples processed during the mission.