Nushkia Chamba
she/her
Nushkia is an astrophysicist at Stockholm University who studies the faint outskirts of galaxies to understand how they form and to come up with a new way to measure the sizes of galaxies.
Highlights
Is an artist, fitness fanatic, hiker, scuba diver, AND scientist!
Originally from Sri Lanka, and has lived and traveled across continents since 2012
Would love to be a professional boxer
You might think it’s pretty easy to measure the size of a galaxy. Just find one in an astronomical image, and pull out a ruler, right? But this seemingly-simple measurement of an important galaxy property is actually pretty difficult for a few reasons, one of which is that many galaxies don’t have an obvious edge in astronomy images. Instead, many galaxies extend from a bright center and fade out gradually, which makes finding the actual edge of the galaxy difficult.
Nushkia Chamba, an astrophysicist at Stockholm University, explains that until now a galaxy’s size has often been defined as the distance from the galaxy’s center where half of the galaxy’s total light is inside that distance and half of the total light is outside of it. While this definition of size generally works, it does sometimes fail. Nushkia points out that a faint and diffuse galaxy may appear to have the same concentration of light as a huge Milky Way-like galaxy—and therefore have the same size by this measure—but the Milky Way’s stars would visually extend much further out. To fairly compare galaxy sizes, and therefore better understand how they formed and evolved over time, astronomers need a measure of size that can distinguish these two cases!
The “light concentration” definition of a galaxy’s size first arose in the era of photographic plates, when only the brightest parts of galaxies appeared in images. Now, astronomers use digital cameras with sensitive detectors that can much more easily detect the faintest parts of galaxies and capture a more complete view of the whole galaxy. Nushkia’s research focuses on faint galaxies, and the faintest parts of brighter galaxies. She studies how far out from the center of a galaxy stars can still form (or formed in the past) from the available gas and dust, which is something that can be directly measured from images. Using the limits of star formation to determine the boundaries of a galaxy gives a measurement of size that’s closer to what our eyes would identify as the size of the galaxy.
Nushkia grew up in Sri Lanka and never pictured herself as an astrophysicist. But she moved to the United Arab Emirates to learn physics at New York University-Abu Dhabi thanks to NYU’s financial support and opportunities. Because of that support, she realized for the first time that “opportunity is out there for people who don’t know what they want to do with their lives and then just figure it out as they go.” She’s always been a visual thinker, but also loves analyzing data, so after a year of high energy physics at the International Center for Theoretical Physics in Italy she found her way to astronomy. As a PhD student at the Instituto de Astrofísica de Canarias in Tenerife, Spain through the Sundial program, Nushkia worked with both astronomy images and computers while connecting with researchers around Europe through Sundial’s partner programs and learning industry skills like machine learning through Sundial’s workshops. She’s now a postdoctoral research fellow at Stockholm University and works with the Rubin Observatory science group there to study faint galaxies—and prepare for doing the same with Rubin data!
When she’s not thinking about faint galaxies, galaxy sizes, or how to measure them, Nushkia has been reconnecting with her artistic side through drawing, painting, poetry, and singing. To her, art is an important part of processing her emotions, especially since she’s been away from her family and friends in Sri Lanka and around the globe since 2012. “It’s been quite tough,” she said. “I’m realizing that I need to find an outlet that’s engaging for me and that creates something beautiful out of every pain and joy life has to offer.” Art provides the time, space, and outlet she needs to connect the dots through all her experiences.
While struggle (and sometimes failure) is a part of science and of being human, perseverance and persistence are as well. That’s a lesson Nushkia has learned throughout her all of her sports experiences, and especially in boxing and acro yoga. She reminds us that “if you stumble and fall, trust yourself to pick yourself back up…and you don’t need to do it alone all the time.”
Lightning Round Q&A: Get to know Nushkia better!
If you could live in any fictional universe, which would it be?
Interstellar!
What animal would you swap places with for a day?
A lion or a horse. I was crazy about The Lion King and about Black Stallion!
If you could travel back in time to any period in human or Earth history, which would you go to?
The 80s—my uncles were musicians, and I’d love to see them in fancy costumes and to see them perform.
What’s your most used emoji?
😌 (slightly smiling face with eyes closed).
And these ones come up a lot too:
😂 (cry laughing face) and
🤦🏽♀️ (brown girl face-palming)