In this series of posts, we sit down with a few of the plenary speakers of the 240th AAS meeting to learn more about them and their research. You can see a full schedule of their talks here, and read our other interviews here!
Is the Milky Way Galaxy (MWG) a weirdo? While measuring global properties of other galaxies is relatively trivial because we can observe the entire galaxy at once. Yet, since we’re inside our own galaxy, it’s challenging to measure its global properties – for example, its history of star formation and mergers, its average motions, or its average chemical composition – and determine how usual or unusual it is. By tying together detailed characterizations of stellar populations in the MWG and studies of large samples of nearby MWG-like galaxies, astronomers like plenary speaker Dr. Gail Zasowski tackle these big questions.
Dr. Zasowski, galactic archaeologist
Growing up, Dr. Zasowski wasn’t one of those astronomy-obsessed kids, and didn’t actually know science was a thing that someone could do until college. In undergrad she took some classes, figured out astronomy was cool, and, thinking she’d study either astronomy or classical archaeology, she graduated with a Latin and Physics degree. By fate or coincidence or something else, today Dr. Zasowski is what some may call a “galactic archeologist”, piecing together the fossil record of our Galaxy using the motions and compositions of its stars.
By the end of college, pursuing a career in astronomy became “sort of a no brainer.” Dr. Zasowski transitioned into graduate school at University of Virginia where she got involved in the Sloan Digital Sky Survey (SDSS), specifically the Apache Point Observatory Galactic Evolution Experiment (APOGEE), a large, near-infrared spectroscopic survey that targets stars in the MWG. Although her involvement in SDSS-APOGEE target selection ended up delaying her graduation by a year, looking back she notes it was a major stepping stone for her future career. After postdocs at Ohio State and Johns Hopkins, she was hired for a tenure-track position at the University of Utah in 2017, where she is currently an Assistant Professor of Physics and Astronomy.
Her ongoing work with SDSS – including the work she’ll be discussing in her talk – uses data from the most recent data release, SDSS-IV. Dr. Zasowski and her team use a range of scales to understand the MWG as a galaxy. Using MaNGA (Mapping Nearby Galaxies at APO) observations across the faces of ~10,000 nearby galaxies, the team characterizes chemical gradients across the galaxies. They also study the MWG itself by analyzing the chemical abundances of stellar populations distributed throughout the Galaxy using APOGEE data.
Another recent piece of work from her group is The APOGEE Library of Infrared SSP Templates or A-LIST (a project I was involved in briefly as an REU student advised by Dr. Zasowski and Dr. Anil Seth in summer 2018!). A-LIST is the first high-resolution near-infrared empirical simple stellar population library, and can be used as templates to model observations of stellar populations. Following the release of A-LIST, Dr. Zasowski and her group are applying techniques used in detailed MWG stellar population studies to APOGEE data for our nearest neighbor, the Andromeda Galaxy (or M31). Dr. Zasowski says this project has become more challenging than expected as they are basically “looking at a big faint thing with a very small telescope.” Right now, they are working on optimizing data reduction for very low signal-to-noise data and then fitting the A-LIST templates to extract stellar population parameters.
A game changer for future astronomy
I asked Dr. Zasowski for any advice she had for astronomy students. Reflecting on her career path, Dr. Zasowski emphasized the importance of getting organized very early and taking good notes, reminding me that we’re not going to remember every thought we have, or every question we want to ask. She also emphasizes the importance of finding an advisor that you actually like talking to, and who is supportive regardless of your career ambitions. Dr. Zasowski also noted “there’s a lot more to the job that we don’t get trained for” – while astronomers are trained to do research, an astronomy career in academia also involves teaching, managing a group, budgeting, and more.
Considering the most exciting recent breakthroughs in her field, Dr. Zasowski pointed to the large stellar surveys of today (like APOGEE) and the upcoming data releases (like SDSS-V, which is currently in progress!). Dr. Zasowski said these are “a game changer” for the way we think about the MWG and the kinds of analyses that are possible. With such a massive influx of data, we’re still getting caught up with the tools we need to analyze them! In her plenary, Dr. Gail Zasowski plans to talk about what we know about other galaxies and the MWG, why we study our own galaxy differently, and why it matters. Come hear about how she’s working to answer questions like: How do we define a MWG analog? What would the MWG look like from the outside? Is the MWG a weirdo? Find out more at her AAS240 plenary talk on Thursday, June 16, 2022 at 3:40 pm PT!
Astrobite edited by Sasha Warren
Featured image credit: American Astronomical Society