Elin
From telescopes in Sweden to astrophysics in California
Learn how international Caltech student Elin Stenmark grew her love for astrophysics, performed undergraduate research, and found a welcoming community.
Caltech astrophysics major Elin Stenmark ‘26 discovered her fascination with the cosmos under the night sky of Sweden, her home country.
"I remember when I was three years old, I got two telescopes for my birthday: one from my parents and then one from my grandma and grandpa," she recalled. "I'd be looking at the stars all the time."
When Elin was 12, she traveled to California with her family, visiting Disneyland and sightseeing in San Francisco. As the family drove by a normal-looking neighborhood, Elin's father mentioned that the greenery around them belonged to a prestigious college.
"That's when the dream began," she said. "I loved learning things, and I enjoyed California, so I thought, ‘Wow, I want to go to college there.'"
Becoming an Astrophysics Major
Elin started researching STEM schools in the Golden State where she could study astronomy, and Caltech immediately jumped to the top of the list. When accepted, she was overjoyed and flew to California to begin her journey to major in astrophysics.
Her first course was Basic Astronomy and the Galaxy, in which she learned the foundations and basics of astronomical research. This semester, she is taking Galaxies and Cosmology, which examines how the universe formed and how to observe interstellar objects.
One class project took her to Palomar Observatory, where students chose an object in the night sky to study.
"My group imaged the photometry of M103, an open star cluster," Elin explained. "We had to write our own code, draw a little circle around a star, add up all of the pixels of light from that star, and then do the same for all of the stars in the picture. Then we used a catalog to compare the brightness against a standard measurement to learn all about the star system."
The hands-on project added to Elin's passion for the field.
"You're literally just looking at light, and you can infer all of these different properties," she said enthusiastically. "That's something so cool about astronomy."
Finding Undergraduate Research Opportunities
The summer after her first year, Elin participated in astrophysics research through Caltech's Summer Undergraduate Research Fellowship (SURF). SURF students collaborate with faculty mentors and receive a grant to work on a project.
Elin worked with the Howard Group under the guidance of Professor Andrew Howard, a leading expert in exoplanet studies. For her SURF research, she investigated a type of exoplanet called Hot Jupiters. These gas giant exoplanets have very short orbital periods, and she wanted to determine how they arrived at such unique orbits.
"We were investigating two different models that assume that Hot Jupiters migrate from some outward position in their star system or planetary system and then come into this inner position [near a star] at some later stage in time," she explained.
To start, Elin compiled a list of known Hot Jupiters and the stars they orbit. She used Python to code pipelines to find exoplanets with a certain mass and radius and then find and analyze their respective suns to determine the star's age.
By further analyzing the findings, Elin hopes to be able to help determine how old Hot Jupiters are and how they have changed their orbital patterns.
"I'm hoping to do a new SURF project next summer to go through more of the data and see if it is possible to endorse either model or if there's some other explanation out there," she said.
Doing research where you get paid to find things out about the universe and teach other people—that sounds incredible," she said. "It's a fulfilling combination of two really cool aspects that get tied into the same job.
Exploring Student Life at Caltech
Despite being thousands of miles from Sweden, Elin has found community through the House system, where students can choose to live in one of eight traditional undergraduate Houses, each with its own unique traditions and activities. Elin joined Venerable House and is currently the athletic manager.
"I handle our inner-House sports engagement. So twice a week, we walk down to our gym facilities and play sports from soccer, basketball, and Ultimate Frisbee," she said. "That's a good way to de-stress, get a sense of community, and build teamwork."
Elin is also a part of Caltech's women's soccer team, where she witnesses the dedication of her peers not only to excel academically but also in their extracurricular pursuits.
"Everyone's here because they have a proficiency in STEM. But to see the people excel in so many areas of their lives and actually take their sports very seriously—it's really cool," she enthused. "I like Caltech because I can fulfill two dreams at once, like playing college soccer and also getting a really good STEM education."
Planning for a Future in Astrophysics
Elin says Caltech has well-equipped her for her future beyond the school. Looking forward, she wants to engage in more research and pursue a Ph.D.
"Doing research where you get paid to find things out about the universe and teach other people—that sounds incredible," she said. "It's a fulfilling combination of two really cool aspects that get tied into the same job."
As Elin advances in her astrophysics studies at Caltech, her interest in the field continues to deepen, and she dreams beyond the boundaries of what the field knows right now.
"One area that particularly intrigues me is astrobiology, a field currently evolving that studies the potential of life in the universe," she explained. "Contributing to answering that question of, ‘Are we alone?' would make me so fulfilled."