CLARKSVILLE, Tenn. — William Keener, an Austin Peay State University physics student, was recently chosen for the highly competitive Solar Physics Research Experience for Undergraduates (REU) at the Center for Astrophysics (CFA), a joint institution between Harvard and the Smithsonian.
His mission: unravel one of the solar system’s enduring mysteries — why solar wind doesn’t behave as scientists expect it should.
“Solar wind is a bit of an unknown,” Keener said. “We know that it’s just plasma that’s been launched off of the sun. And we know from the Voyager spacecraft that the heat of the solar wind doesn’t fall off adiabatically like we expected. Instead, it goes through cycles of being heated and cooled. And that’s really weird.”
Chasing Turbulence in Space
Keener’s 10-week project focused on analyzing data from NASA’s Parker Solar Probe, the spacecraft flying closer to the sun than any mission before it. His research examined two methods of solar wind heating, with primary emphasis on turbulence — the same phenomenon experienced in airplanes and water, but occurring in the plasma streaming from our star.
The challenge lay in understanding the “helicity barrier” — a length scale where energy distribution in the solar wind encounters resistance, preventing it from cascading down to smaller ion scales that drive key plasma processes.
“At a certain scale, the energy transfer hits a roadblock before it can reach those tiny ion scales,” Keener said. “We were analyzing regions where the barrier would be active and seeing if, with the Parker Solar Probe’s data, we were able to define the turbulent [flow] regime.”
The work required identifying “imbalanced turbulence” — instances where fluctuations in magnetic field and velocity show significant directional bias, with one direction much stronger than the other. Keener said the chaotic nature of turbulence actually follows a normal distribution via stochastic processes.
Beyond the Research
What struck Keener most wasn’t the scientific challenge, but the institution’s approach to community building. The Center for Astrophysics provided an environment that balanced serious research with memorable experiences. Keener frequently ate lunch on the building’s roof, overlooking the Boston skyline, sometimes accompanied by the sounds of outdoor ping pong games.
“Despite it being whole conglomeration of random people at the CFA, they wanted us to build a community more than they cared about their research results,” he said. “They wanted to make sure that we were well adjusted to being at the CFA, and I think that’s really cool.”
The program included extensive professional development opportunities. Students had weekly coffee sessions with scientists covering solar physics from the sun’s core to its interactions with Earth, and attended presentations on grant writing and graduate school preparation. They also integrated into the broader research community through ice cream socials, tennis and chess clubs, and summer barbecues.
“We had 20 different emails just saying, ‘all right, here’s some events that are going to be happening at the CFA and in the area that are optional for you, but we would like to see you there,'” Keener said.
The Learning Curve
The program threw substantial technical challenges at students from their first day. Keener had to master complex data analysis techniques, often writing code for procedures he didn’t initially understand.
“There was definitely a point where I thought, ‘What am I even doing? This is absurd,'” he said. “I didn’t always know what work I was doing for the first few weeks, and I was just writing out code … I can write out code all day, but I had no idea what the processes were that I was doing.”
The real test came during week four, when many mentors departed for a major solar physics conference.
“That was maybe the scariest part; ‘All right, no one’s around. You’ve still got to continue trying to work on this,'” Keener said. “Theoretically, we knew everything we needed to continue for that week. In practice, that wasn’t 100% true.”
His mentors — a postdoc specializing in turbulence and a full scientist who was an instrument scientist for the Parker Solar Probe — implemented an open-door policy and a shared question document that allowed for constant communication and reference.
Lessons in Research Reality
The experience taught Keener valuable insights about real-world research that classroom learning couldn’t provide.
“One of the biggest things I learned is how important proper data filtering is,” he said. “Raw data can be really messy, and you have to be careful about the assumptions you make. It’s all about making sure you’re getting accurate results.”
Beyond the technical lessons, Keener was struck by the collaborative and supportive atmosphere among the researchers.
“What really impressed me was how positive and encouraging everyone was,” he said. “There was this great energy where people were genuinely excited about the work they were doing. That enthusiasm was contagious – it made the whole research environment really motivating.”
Looking Forward
The REU experience has influenced Keener’s career trajectory. His continued collaboration with the Smithsonian on the solar wind heating project provides ongoing research opportunities while completing his Austin Peay degrees (a triple major in physics, computer science and mathematics).
The program’s emphasis on both technical skills and professional development prepared participants for graduate school and research careers. For Keener, the experience proved that world-class research institutions value community building alongside scientific achievement, a lesson that extends far beyond solar physics.
About the Austin Peay College of STEM
The College of Science, Technology, Engineering & Mathematics (STEM) provides studies for students in the areas of agriculture, astronomy, aviation sciences, biology, chemistry, computer science, earth and environmental sciences, engineering physics, engineering technology, information technology, mathematics, medical laboratory sciences, radiologic sciences and physics. Our outstanding, discipline-based programs are student-centered and designed to prepare students for responsible positions at all levels of research, industry, education, medicine and government.
