Astronomy PhD Student Explains Outer Space on YouTube

January 30, 2020
Sarah Pearson

This has been a busy year for Sarah Pearson. The fifth-year Astronomy PhD student from Denmark launched Space with Sarah, a YouTube channel that answers tough questions about the cosmos; received the 2017 Women in Physics Prize from the Niels Bohr Institute; and won the 2017 Graduate Student Prize from the Astronomical Society of New York—all while finishing her doctoral dissertation. Pearson spoke with the Graduate School about her YouTube series, her astrophysics research, and how the two complement one another.

GSAS: What inspired you to start Space with Sarah?

Sarah Pearson: My love for teaching. Throughout grad school, doing outreach events and talking with my classes has made me excited about my subject and helped me to see the “bigger picture.” As you do your PhD, you become more and more specialized, and it’s useful to take a broader look at the field. Making science more accessible is one of my goals, too. Everyone should be able to learn about how nature works and how our world is tied together. Finally, I felt that women in physics were not very well represented. I thought it was important to show young girls and boys that women are scientists.

GSAS: Your videos’ production values are really impressive. How do you keep the quality so high?

SP: Being in New York helps. I don’t think I would have been able to make Space with Sarah somewhere else. I very luckily was paired up with my producer, Brett Van Deusen, through a mutual friend. Brett is an audio expert, but his dream was to produce science videos, and I wanted to write and host, so it was a perfect match. The high quality is thanks to Brett. My initial idea was just to stand in front of a PowerPoint, but I’m in front of a green screen instead. We have an animator and a graphic designer helping us out, too.

GSAS: In your videos, you discuss black holes, the expansion of the universe, colliding galaxies, and other complex topics. How do you make them engaging to a general audience?

SP: I do my best to remember what excited me when I went into the field—for example, analogies that anyone can understand. I love writing, and try to make every episode into a story. I also try to remember what I liked—and didn’t like—about teachers I’ve had over the years. I avoid using phrases like “as we all know” and “trivially.” I remember hating that in class, because if you don’t know those facts, you already feel lost. Keeping my target audience—a younger crowd with no background in science—in mind has been important, too. When I write an episode, I know much more about the subject than I include. I have to remind myself that I’m not doing it to show my professors how much I’ve learned. That’s one of the most difficult things: keeping it simple.

GSAS: What has been most rewarding about Space with Sarah?

SP: Young girls have reached out to me on social media to say that I’m their role model, that they want to study physics, and have asked me for advice. That really gets to me.

GSAS: What advice do would you give to other graduate students who want to launch public outreach projects?

SP: Make your project about what most excites you, because that excitement translates. Also, talk to people. Tell everyone you meet what you’re doing. Random connections made a huge difference for me. And just get started. I came up with the idea for Space with Sarah and wrote the first episode within a week and a half. It can be intimidating to start, but just do it and see if it works.

GSAS: How have you balanced Space with Sarah with the demands of graduate study?

SP: The YouTube series actually gave me energy for my PhD studies. When I started the series, I was stuck in nitty-gritty details of my research and wasn’t feeling very motivated. This project made me excited about science again.

GSAS: How did you become interested in your field?

SP: As a kid, I loved math, physics, and chemistry. I was always fascinated by nature: how everything worked. When I learned in school that everything you touch is from the periodic table that blew my mind. And the big questions drove me crazy: Is the universe infinite? Is there life beyond earth? As it turns out, studying the subject for fifteen years doesn’t help you answer all of those questions. [Laughs.]

GSAS: What are you researching for your PhD?

SP: My thesis is about small galaxies. We live in the Milky Way Galaxy, which is a spiral galaxy with roughly 100 billion stars. I study what are called dwarf galaxies—they are smaller, and have roughly a billion stars or fewer. Part of my thesis is about what happens when these small galaxies collide with each other. That’s interesting because we think that galaxies grow by colliding with and gobbling up smaller systems. By studying dwarf galaxies’ interaction nearby, we can get a sense of what happened in the early universe. I am also studying how groups of stars that orbit the Milky Way are torn apart by the galaxy’s gravitational tidal field. As they orbit the Milky Way, these stars feel the gravity of the entire galaxy and are stretched into long stellar streams. We can investigate dark matter, which is invisible but dominates the mass in galaxies, by looking at how the mass in our own galaxy pulls on these stellar streams.

GSAS: Were you surprised to win the Women in Physics Prize so early in your career?

SP: I was surprised! They had already invited me to that conference to speak about getting young people involved in science, and they told me I had won the prize a few days beforehand. The prize was specifically for my research achievements. That was great, because people at the conference who don’t know me might have thought that I spend all of my time on outreach, which is definitely not the case.

GSAS: What do you enjoy doing in your (limited) free time?

SP: I really like singing. Maybe I’ll turn my YouTube channel into a singing channel. [Laughs.]

GSAS: You could write songs about space.

SP: My producer would have a heart attack.

Pearson explains how black holes form as part of her YouTube Series

Watch her other videos here.