Karin Sandstrom

Physics Department

2020 Faculty Mentor Program Mentor

Mentee: Megan Li

Can you tell us a bit about your research?
I study the interstellar medium and star formation in galaxies. The interstellar medium is a low density mixture of gas and dust that pervades a galaxy. Stars form from this reservoir of gas when clouds and clumps within them become dense enough to collapse under their own gravity. Dust is critical to how the interstellar medium works -- it is responsible for heating and cooling in the gas, for aiding chemical reactions, and for shielding dense regions from energetic photons. I use observations of nearby galaxies at ultraviolet through radio wavelengths to measure the amount and properties of dust and to learn how it affects the physics of the interstellar medium.

Did you do research as an undergraduate? How did you get started in your current field?
I was fortunate to have many research opportunities as an undergraduate. In my first semester of college I took an introductory astronomy course to fulfill a science requirement and fell in love with the topic. I changed my major to astronomy right then and went to go talk to the professor to thank him for his life-changing course. He offered me a position working in his research group. The opportunity he gave me led directly to other projects, which led me to where I am now. My start in the field truly occurred on that day he offered me a job! I ended up writing my senior thesis with him as well. I participated in summer research projects each summer and worked on a junior year research project with a different advisor at my college.

Who are some of your most memorable mentors, and how did you meet them?
The professor who offered me a job after the introductory astronomy course was Dr. David Latham at the Harvard-Smithsonian CfA. He patiently taught me basic computer skills at first. Later I studied white dwarf stars in binaries in an attempt to constrain their masses. I worked with him throughout college, concluding with my senior thesis.

The summer after my freshman year of college, I went back to my home state of Washington and worked with Prof. George Wallerstein at the University of Washington. He was kind enough to respond to my out-of-the-blue email searching for a summer research position. We worked together on a study of diffuse interstellar bands, which are a mysterious set of interstellar absorption features which are probably related to dust.

I was lucky to participate in the National Optical Astronomy Observatory's REU program during the following summer. My mentor there was Dr. Caty Pilachowski. We studied a type of variable stars (called RR Lyrae stars). My work with Dr. Pilachowski was the first time I was able to observe with a telescope for research purposes, which was exhilarating. She was also extremely patient in guiding me through the process of writing up our results for publication.

In my junior year of college, I worked with Prof. Alyssa Goodman on a project about the dust extinction and magnetic field strength in molecular clouds. This project actually introduced me to many of the topics I still study today.

What's the most useful piece of advice someone gave you?
At the end of a fruitful research project, we should have created many more interesting questions than we have answered.