What They Learned: Reilly Milburn ’19

Physics and astronomy double major Reilly Milburn ’19 used his thesis to investigate both an exciting kind of astronomical object and the tools used to detect these objects.

Senior thesis research took physics and astronomy double major Reilly Milburn ’19 out of this world. By studying planets in other solar systems and the tools used to observe them, Milburn gained an intimate perspective on the daily kinematics of our cosmos.

Milburn’s project, although dense and technical in realization, has a simple and elegant conceit. It begins with astronomical objects known as transiting exoplanets.

“Exoplanets are planets that exist outside of our own solar system—that is, they orbit stars that are not our Sun,” said Milburn. “A transiting exoplanet is a special type of exoplanet that passes directly through our line of sight to a star.”

When these transiting exoplanets pass in front of stars, astronomers can measure a decrease in the star’s brightness. This measurement can then be used to track the exoplanet in a process called “following up.”

“When we ‘follow up’ on an exoplanet, it simply means we are confirming from previous observations that an exoplanet does exist somewhere it has already been reported,” said Milburn. “For my thesis, we wanted to see if we could do this follow-up work with Haverford’s modestly sized 16-inch-diameter reflecting telescope.”

This question of whether or not Haverford’s observatory could support such follow-up work actually became the central investigation of Milburn’s thesis. He arrived at this guiding question with the help of Jessie Christiansen of the NASA Exoplanet Science Institute.

“The summer before my senior year, I had the privilege of meeting exoplanet researcher Jessie Christiansen when she gave a talk about how citizen science can be used to assist exoplanet detection,” said Milburn.

Christiansen’s invocation of citizen science—scientific research conducted by amateur scientists with relatively common equipment—led Milburn to be curious about what kinds of astronomical tools are actually necessary for exoplanet research. Under the tutelage of his thesis advisor, Associate Professor of Physics and Astronomy Karen Masters, Milburn explored this question by determining what types of transiting exoplanets can be detected from Haverford’s observatory.

“What we found is that Haverford should be able to detect large exoplanets orbiting bright stars,” said Milburn. “It’s super exciting that such groundbreaking research can be done in the observatory on campus.”

What did you learn from working on your thesis? 

I feel like I have learned a great deal from my thesis work. Being that no Haverford professor specializes in exoplanet research themselves, it felt even more so like an independent research project. I was able to get lots of hands on experience with the astronomical instruments and software Haverford has to offer, especially the 16-inch telescope and the CCD camera. Having completed the thesis, I definitely feel comfortable operating a telescope and taking my own images.

What is your biggest takeaway from the project?

I would say the biggest takeaway for me was learning about all the challenges that come with taking exoplanet data, as well as astronomical observations generally. Some challenges we were able to tackle by the end of the year, such as getting the dome to move properly, or pointing the telescope correctly. However, some challenges are simply unavoidable. The weather proved to be a bigger obstacle to this thesis than I initially thought. As I continue to work in astronomy, I certainly won’t take clear skies for granted.

What are your plans for the future and does your thesis have anything to do with guiding your future career path?

I have accepted an offer from the University of North Carolina at Chapel Hill to pursue my Ph.D. in their physics and astronomy department, starting in the fall. I hope to continue exoplanet research in the near future as part of my Ph.D. The thesis allowed me to explore exoplanets in great depth, and I am definitely excited to learn more about them. I very much enjoyed being able to take my own astronomical data for the thesis, and I hope to continue hands-on work with astronomical instruments in the future.