[From Spring 1997 issue of A&S Perspectives]
When undergraduate Vassilious Bezzerides attempted to gather data for a recent research project, the whole process made him queasy. That's understandable given that his laboratory was a NASA aircraft plummeting and then climbing through the sky at 400 miles per hour. The good news: the plane's gyrations were intentional, to create conditions that approximate the weightlessness of space.
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Bezzerides was one of six UW physics undergraduates to fly in NASA's reduced-gravity aircraft as part of SURF Academy (Students Understanding Reduced-gravity Flight) at Johnson Space Center in Houston. The pilot program, funded by NASA and administered by the Texas Space Grant Consortium, allowed students to learn firsthand what it takes to prepare and perform experiments in a weightless environment.
"In a setting like this, you must work out all the details ahead of time," says Tom Matula, research scientist at the Applied Physics Laboratory. "You can't make mistakes. You can't do it over."
Matula should know. He was involved in a zero-gravity program in Europe two years ago. When he tried to seek similar opportunities for UW students last year, he discovered that no national program existed in the U.S. "I contacted former astronaut Pinky Nelson, who at the time was a UW Vice Provost, and he spoke with his colleagues at NASA," says Matula. "As a result, SURF Academy was born." Of the 23 teams selected for the program, two were from the UW. Washington Space Grant paid their airfare to Houston.
So That's Why They Call it the Vomit Comet
SURF Academy lasted two weeks. During the first week, students fine-tuned their experiments and participated in physiological testing to prepare them for zero gravity. The second week, they took to the skies.
Each team flew twice, with each flight lasting about two hours. The aircraft followed a roller coaster-like flight pattern over the Gulf of Mexico, maneuvering through steep climbs and descents. At the top of each ascent, passengers inside the aircraft experienced the weightlessness of zero gravity. "It was pretty wild," recalls Bezzerides. "You could easily lose your sense of which way to go." Given the harrowing ups and downs, you could also lose your lunch. Many students did, which explains the aircraft's nickname, the vomit comet.
"I just felt nauseated from moment one," admits Bezzerides. "It was quite literally a gut wrenching experience for me." Teammate Jarred Swalwell fared better. "I had no problems the whole time," he says, adding with a shrug, "NASA says that people are just wired differently."
Whatever the state of their stomachs, the students had experiments to conduct and limited time in which to complete them. Each flight was divided into four sets of ten parabolic arcs--stomach-turning ups and downs. Depending on the precise trajectory, the student teams and their experiments were exposed to about 25 seconds of zero gravity, 30 seconds of one-sixth gravity (the same as on the surface of the moon), or 40 seconds of one-third gravity (the same as on Mars) with each arc.
"We were testing a few different theories in our experiment, so we looked at different things with each parabola," says Swalwell. "During the last set, we just enjoyed the flight."
Testing Complex Theories
Although the dramatic flights were memorable, they were just part of a research process that began late last year, when the students learned that their proposals had been accepted for SURF Academy. In a scant three months, the two UW teams accepted for the program had to design viable research experiments, build the necessary apparatus, and test it. To complicate matters, for safety reasons the apparatus was required to withstand 8 Gs of acceleration--a tremendous amount of stress--even though it would only be subjected to 2 Gs.
One UW team, coached by Matula, designed experiments to study the effects of zero gravity on single-bubble sonoluminescence. Sonoluminescence is the emission of light caused by sound energy, which scientists believe may be useful in detecting and destroying harmful pollutants. To generate sonoluminescence, scientists use sound waves to suspend a bubble in a liquid. Then the sound pressure is increased and the bubble expands many times its original size, finally collapsing violently, releasing a flash of visible, bluish light.
How does the zero gravity environment fit in? Some scientists theorize that the light emission depends on the bubble's buoyancy, which is caused by gravity. The students tested the theory by measuring the light emission from sonoluminescence in zero gravity and in hypergravity (approximately 2 Gs). "The data did what we expected, but it could be the result of cabin pressure rather than zero gravity," says Swalwell. "We have to do one more experiment in the UW lab to check on some of the data."
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| Two UW Teams were accepted to NASA's SURF Academy. Participants included (clockwise from upper left) Jarred Swalwell, Mike Chittick, Paul Hilmo, Shanti Rao, Kevin Strecker, and Vassilious Bezzerides (not pictured). |
The other UW team, coached by Rich Mittleman, research assistant professor of physics, explored questions surrounding the building of a magnetic optical trap--a method of trapping a cloud of atoms for use in experiments--by using lasers and magnetics. The students tested a "stablilized diode laser" that would be used to make the trap.
"The first day, we tested how well the laser would run by itself," explains team member Shanti Rao. "We discovered that diode lasers do not work well in planes. The second day, we added a feedback to continually monitor and correct for the laser output. With that change, we got really good results." Rao adds with a grin, "There were a lot of people in the Physics Department who didn't think we could pull it off, but we did. Getting good results was incredibly satisfying."
Several of the students were so intrigued by conducting zero gravity research that they plan to pursue it further. Of the six UW students who attended SURF Academy, three have applied for summer internships with NASA in Houston. All six students insist that it's not the flight that hooked them, but the whole research process.
"The flight was fun," says Bezzerides, "but by far the best part for me was starting with an idea, constructing it, and trying to make it work. And when it does work . . . it's a real adrenaline rush."
OK, but didn't they gain any profound insights from floating around, weightless, at 30,000 feet? Well, maybe one. "I'll never look at plane rides the same way again," says Kevin Strecker. "When I got on the 727 to come home, it just seemed so . . . lame."