Learning That Defies Gravity
Geology majors conduct research in zero-g as part of an elite NASA program.
By Matt Gray
Photos courtesy of NASA
Danyelle Phillips ’14 wasn’t set on a major when she graduated from high school, but she knew she wanted to leave the rural confines of her home in central Virginia to experience everything the world has to offer. This summer, Phillips got her wish, partaking in a project that was literally out of this world.
“Weightlessness was pretty cool,” Phillips says about being part of a Bryn Mawr team that rode aboard a NASA jet that mimics near zero-gravity conditions through a series of high-flying plunges. “It was way more intense than I expected. You’re floating for 30 seconds at a time. If you don’t hold on to anything, you’ll end up with your feet on the ceiling.”
Phillips joined fellow geology majors Alice Clark ’12, Simona Clausnitzer ’14, Hannah Gatz-Miller ’12, Christina Lee ’12, Mary Schultz ’12, and their faculty advisor, Assistant Professor of Geology Selby Cull, in Houston this summer as part of NASA’s Reduced Gravity Education Flight Program, which allows student researchers to conduct experiments aboard a specially modified Boeing 727 that has been dubbed “The Vomit Comet.” (Anna Woodson ’12 was also part of the research team, but was unable to make it to Houston.) To create a zero-gravity environment, the plane does several parabolic maneuvers over the course of a two-hour flight, during each of which it climbs to an altitude of nearly 34,000 feet and then goes into a 15- to 25-second free fall.
“It was one of the craziest feelings I’ve ever experienced,” adds Lee. “Right before we were going into zero-gravity, my heart started to race in anticipation. Then all of a sudden, I was pulled off the ground and lost all control of my body. It felt like a giant roller coaster.”
“It wasn’t that it was hard to tell up from down,” recalls Gatz-Miller. “It was more like the concepts didn’t even exist. I thought it would feel more like swimming, but it really felt nothing like it because there was nothing to push off against.”
For their experiment aboard the plane, the team was interested in measuring the porosity of Martian soil simulant—weathered volcanic ash from Hawaii’s Mauna Kea volcano—using a portable spectrometer at a range of microgravity levels, including the specific gravity of Mars. The soil sat inside a box designed by the team and built by Richard Willard, director of Bryn Mawr’s Science Support Service Department. The box has two irises that allow the researchers to insert the spectrometer and conduct their tests without releasing the soil during reduced-gravity conditions.
The initial concept for the experiment came from Cull, who prior to coming to Bryn Mawr, made headlines as part of a research team that found evidence of possible water on Mars. But the project itself was completely led by the students.
The journey to Houston began in earnest in October 2011, when the team submitted its initial proposal, and would be nearly as tumultuous as the flight itself. When NASA made its initial selections, Bryn Mawr was told it hadn’t made the cut due to a lack of funding that greatly limited the number of schools that could participate. But when additional money became available, the team was informed in April they’d been granted a spot, leading to a hectic final few weeks of the semester.
In addition to getting ready for finals and graduation, the students had to write up a Test Equipment Data Package (TEDP) that detailed every step of their experiment to demonstrate it could be done safely in the turbulent environment of the plane.
“Four out of six of us were attempting to finish our theses and graduate, and the other two had all their finals,” says Gatz-Miller. “We ended up having to write our TEDP in mid to late May, when we were literally scattered across the country and half of us had intermittent Internet and phone service. There were a lot of phone conferences at odd hours.”
And there was still another hurdle before the team would get down to its experiment—and the experience of weightlessness. Once the team members arrived at Houston’s Ellington Field, they had to run through their experiment step-by-step again for a group of NASA engineers.
“If they don’t approve the experiment, you’re done,” Phillips recalls. “It was really nerve-wracking. They had so many questions because they were worried about the soil contaminating the plane. The engineers kept coming up with all these ideas that would have made the experiment much more complicated, and we’re sitting there going, ‘We’re flying tomorrow; how are we ever going to get this stuff done?’”
The experiment was saved thanks to their NASA-supplied mentor Tamra Davis.
“She told us that we just needed to come up with a method so that we never took the probe out when the second iris is open,” Phillips explains. “We were like, ‘Oh that’s really simple. Why’d they have to scare us so much?’”
The students flew in groups of three on two different days. Prior to the flight they were given medication to help minimize the effects of the trip. “I think we were all nervous, but once you got into the air the adrenaline just took over,” recalls Clausnitzer, who flew in the second group along with Phillips and Schultz.
Gatz-Miller described the experience on the blog set up by the team:
“During the 32 Zero-G parabolas, we had to time our spectra measurements to about a second after the no-gravity started heading back into microgravity. The gravity changed very quickly, so we ended up with a range of microgravity spectra measurements, not just those from Mars. Our best data likely came from the four specifically lunar and Martian gravity parabolas near the end. Tamra ended up taking over for one of our teammates when she became horribly ill, but in the end, we had the data.
“After a total of 2.1 flight hours, we landed back at Ellington, content in the knowledge that every other plane ride for the rest of our lives is likely to be incomparably dull.”
While no one in the second group got sick, the experiment didn’t go nearly as well for them. After having their flight postponed due to bad weather, the group finally made it into the air on their last day in Houston. The box jammed after the third parabola, and some of the soil dust started to escape, forcing the NASA crew to bag up the box before any data could be collected. The results of the experiment were inconclusive because the soil didn’t react to reduced gravity quite as expected.
“We had assumed that the soil would settle out of the air and that we’d be able to measure the spectra,” explains Cull. “But, in fact, the soil didn’t settle out of the air. But that’s just part of the scientific process. You design an experiment, and if it doesn’t work, you go back to the drawing board and try it again.”
And that’s just what they’re going to do. This year another team of students will again try to measure the porosity of Martian soil. This time, however, they’ll be measuring changes in volume using a thin, clear box with visible measurement markings on the outside.
“Our plan is to use a video camera to record what happens to the soil during the flight, so that the experiment itself will be less stressful,” says Phillips, who will lead this year’s team and will be joined by Clausnitzer (last year’s team leader). “One thing we learned about working in zero-gravity is that you’ve got to keep it simple.”
The time spent in microgravity is more than just fun; the research could be extremely valuable, says Cull, who was part of the mission control team for the Phoenix Mars Lander in 2008.
“One of the things we don’t fully understand about the soil of Mars is the spaces in between the grains, and it’s hugely important,” she explains. “Soil porosity affects everything from
being able to adequately decipher satellite images to landing rovers. It’s really important for us to understand this stuff, and there’s simply no way to measure it on Earth.”
No matter what the outcome, Cull says that working with the microgravity team was one of the most rewarding experiences of her young academic career.
“I’ve already had the pleasure of working with a lot of really gifted students, but this team … I’m just in awe of how they put all this together,” she says. “They wrote a NASA grant themselves, designed this complex experiment, built the equipment they’d need, engaged in outreach. They were amazing.”