 
Sharon
Cobb,
Marshall Space Flight Center, Huntsville, Ala.
 | | Dr.
Sharon Cobb is a materials scientist at NASA’s Marshall Space
Flight Center in Huntsville, Ala. |
NASA
scientist helps develop facility to study materials in out-of-this-world
Space Station lab
Aug. 15, 2002
- As a young woman, Sharon Cobb became fascinated with materials
when she watched molten metal being formed into huge shapes at a
steel foundry in Birmingham, Ala., where her father worked.
Today, she
is the lead scientist developing an important facility for studying
materials in an out-of-this-world laboratory -- the International
Space Station.
“Materials
science is an integral part of our everyday life,” said Dr.
Cobb, a materials scientist at NASA’s Marshall Space Flight
Center in Huntsville, Ala. “If you think about the things you
use in your daily life, from your coffee cup to the car you drive,
you realize that having the right material is a key to how things
work. As a materials scientist, I study the chemical and physical
make up of materials and use what I learn to make new or improved
materials.”
During her
16 years at the Marshall Center, Cobb has participated in several
materials science experiments flown on NASA’s Space Shuttle.
Cobb is using that experience as lead scientist for the Materials
Science Research Rack -- soon to be the main facility on the International
Space Station for materials science investigations. Astronauts will
install the floor-to-ceiling, 40-inch (1-meter) wide rack in the
Station’s Destiny Laboratory.
Cobb is working
with Marshall Center engineers who are developing the first Materials
Science Research Rack and integrating the first two experiment modules
that will fit inside the rack. Scientists and engineers completed
a critical design review of the research rack in June, which means
NASA has approved the design phase and is ready to start building
the facility.
Cobb and other
scientists will use the rack’s furnaces to melt and solidify
many different types of materials. These materials will be processed
in orbit, and returned to Earth for characterization.
“Forget
science fiction images of huge factories in space,” said Cobb.
“Our goal is to use the low-gravity environment created inside
a spacecraft -- like the Space Station orbiting Earth -- to learn
how to control the way materials form. Then, scientists can bring
that knowledge back to Earth to improve manufacturing processes.”
Manufacturing
represents 17 percent -- or $1.2 trillion -- of the U.S. gross domestic
product. That means even modest improvements in materials and their
production can have great economic impact. Better materials not
only mean better spacecraft, but can also mean better computers,
automobiles and buildings.
“The first
two fundamental materials science experiments are just getting started
on the Station inside the Microgravity Science Glovebox, a new facility
that encloses small furnaces and uses gloves to enable the crew
to change out samples,” said Cobb. “These initial glovebox
experiments will provide data that we can use as we develop more
complex experiments in the larger furnaces inside the Materials
Science Research Rack. “
The Materials
Science Research Rack is scheduled to be delivered to the Station
in late 2004. The rack will accommodate two different experiment
modules with exchangeable furnace inserts.
“When
people ask me why you need different types of furnaces, I explain,
that for a simple building project, you usually need several different
tools -- drill bits, saws and screwdrivers,” said Cobb. “To
study materials in space, we need many types of equipment to provide
a variety of processing conditions for various types of materials.”
In laboratories
at the Marshall Center, Cobb is conducting experiments with materials
that may be processed in Space Station furnaces. She works with
germanium, a semiconductor used in electronic devices and mercury
zinc selenide, a material that has the potential to be a new state-of-the
art infrared detector which could be used to map temperature variations
in everything from human bodies to rockets.
Engineers are
using the Marshall Center Microgravity Development Laboratory to
help design, build and test the Materials Science Research Rack
and one of its furnace inserts. Marshall engineers are building
a flight-like Quench Module Insert Furnace that will be tested at
Marshall and then delivered to the European Space Agency, which
is responsible for building the Materials Science Laboratory Experiment
Module– the systems that will power, cool, and control the
furnace.
At the Microgravity
Development Laboratory, furnace operations are tested by melting
and solidifying pure aluminum samples inside a breadboard model
of the furnace to 1652 degrees Fahrenheit (900 degrees Celsius).
The flight furnace will operate at temperatures up to 1400 degrees
Celsius (2550 degrees Fahrenheit). The furnace is lighter and uses
less energy to operate than most of the furnaces flown earlier on
Shuttle missions. It weighs 55 pounds (25 kilograms) versus several
hundred pounds and it operates with 200 watts of power versus 2500
watts of power.
The other experiment
module that will initially be installed in the Materials Science
Research Rack is being built by the Consortium for Materials Development
in Space at the University of Alabama in Huntsville — one of
15 NASA Commercial Space Centers sponsored by NASA’s Space
Product Development Program at the Marshall Center. This experiment
module has two exchangeable furnaces that will be available to commercial
companies to process semiconductors, optical glass preforms, metals
and composites in space. Both furnaces are modular and can be removed
for repairs or replacement.
The Telescience
Support Center, also located in the Microgravity Development Laboratory,
will be used to monitor and control experiments in the Materials
Science Research Rack once it has been installed on the Station.
Flight-like
training models of the Materials Science Research Rack including
its experiment modules will be delivered to the Johnson Space Center in Houston, Texas, for astronaut training. To ensure astronauts
know the importance of doing materials science experiments, Cobb
teaches an introductory materials science class at the Johnson Center -- including hands-on laboratory experiments -- to new astronaut
candidates.
While a few
of the astronaut candidates have advanced degrees in materials science,
many are pilots, astrophysicists or from other unrelated fields.
To perform these experiments aboard the International Space Station,
it is important for the astronauts to understand how and why materials
are studied in space.
“I always
tell the astronauts that the goal of materials processing in space
is to develop a better understanding of how processing affects materials
properties and structures, said Cobb. “With this knowledge,
we can reliably predict conditions required on Earth to achieve
improved materials.
Cobb, a Birmingham
native, earned a doctorate degree in materials science and engineering
from the University of Florida in Gainesville and bachelor’s
and master’s degrees in materials engineering from the University
of Alabama at Birmingham.
She has recently
been selected to participate in the NASA Professional Development
Program. This leadership training program provides participants
with an opportunity to broaden their understanding of NASA agency
goals and policies, and facilitates communication with other NASA
field centers and government agencies.
As a part of
this program, she recently was assigned to NASA Headquarters in
Washington, DC for one year. The Materials Science Research Rack
and its experiments are sponsored by NASA’s Office of Biological
and Physical Research.
All text
and photos for this story were provided by Marshall Space Flight
Center.
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