Balancing Homework and A.P. Classes, These High Schoolers Discovered Four Exoplanets

Thanks to a Harvard-Smithsonian mentoring program, high school students Kartik Pinglé and Jasmine Wright helped discover new worlds

Five planets lined up in the night sky, from a large planet partially visible in foreground to four smaller sub-Neptune planets
An artist's rendering of the five-planet system that orbits star HD 108236, or TOI-1233. In the foreground is a hot, rocky planet that resembles Earth. NASA / JPL-Caltech

Like many ambitious high schoolers around the country, 18-year-old Jasmine Wright and 16-year-old Kartik Pinglé navigate busy schedules, packed with volleyball, fencing, piano practice, demanding classes and prepping for A.P. exams.

Unlike most of their peers, however, Wright and Pinglé just discovered four new worlds. Last year, the pair helped confirm the existence of four exoplanets that revolve around a sun-like star about 200 light-years away from Earth. The high schoolers and their mentor, Tansu Daylan, a postdoc at the MIT Kavli Institute for Astrophysics and Space Research, co-authored a peer-reviewed paper on their research, which published in The Astrophysical Journal on January 25.

They may be the youngest astronomers ever to make such a discovery, says Clara Sousa-Silva, a quantum astrophysicist at the Harvard-Smithsonian Center for Astrophysics (CFA). Her research on phosphine recently made headlines for its connection to potential life on Venus.

In her off-hours, Sousa-Silva directs the Student Research Mentoring Program (SRMP), which pairs young astronomers like Pinglé and Wright with scientists at MIT and Harvard for a one-year-long research project. Founded in 2016 by Or Graur, a former CFA postdoc, the program accepts about 10 to 15 students each year, with a focus on recruiting budding astrophysicists from underrepresented racial and gender identities.

As well as pairing students with mentors, Sousa-Silva adds, “we teach them how to be scientists.” This includes teaching students how to read a scientific article, the basics of coding, how to present their research and how to combat imposter syndrome in a competitive field.

Balancing Homework and A.P. Classes, These High Schoolers Discovered Four Exoplanets
High schoolers Jasmine Wright, left, and Kartik Pinglé, right, helped researcher Tansu Daylan at MIT discover four new exoplanets last year. Courtesy Jasmine Wright and Kartik Pinglé

Sousa-Silva, as a self-professed B-student in college, insists that the program doesn’t recruit only straight-A pupils. “They don’t need to have perfect grades, or remember everything they learn,” she says.

“I definitely think the next big discoveries in astronomy are not going to be facilitated by the next generation of telescopes, they’re going to be facilitated by the next generation,” Sousa-Silva continues. “I want to make sure that those scientists… are students who actually want to do science and would enjoy it.”

Wright and Pinglé were selected for the 2019-20 SRMP cohort after a rigorous application process and began researching with Daylan in the fall of 2019. They met with Daylan twice a week after school on MIT’s campus, all while balancing their many extracurriculars: Wright, now a senior at Bedford High School, works for the city, figure-skates, competes on her school’s robotics team and plays varsity volleyball (and speaks Hungarian, Spanish and English). Pinglé, a current junior at Cambridge Rindge and Latin School, fences, plays classical piano and just wrapped an internship in the Cambridge mayor’s office.

Their search for exoplanets began with heaps of data. Daylan tasked Wright and Pinglé with sorting through a list of potential planet candidates from TESS, Transiting Exoplanet Survey Satellite, a two-year project run by MIT and the Harvard-Smithsonian Center for Astrophysics, that is scanning outer space for far-away evidence of exoplanets, planets that orbit stars outside our own solar system.

“In the first month I remember telling my mom, ‘Mom, I don’t think we’ll publish anything. This is a great project, but I don’t know if we’re going to get anywhere,” Pinglé remembers. “And then a few months passed, and by the time we actually started writing the paper, I was like, ‘Oh, I was very wrong.’”

TESS identifies potential planets by looking for their shadows as they transit stars’ surfaces. “If the satellite is looking at the star, and a planet passes in between the star and the telescope, you will see a large drop in light from that point, sort of like an eclipse blocking the light from the star,” Pinglé explains. If TESS notices a periodic dip in light, that could signal the presence of a planet revolving around the star.

Pinglé wrote code to search TESS’ list of planet candidates—also known as “TESS Objects of Interest” (TOI)—for solar systems that might contain multiple planets. That’s how the team happened upon TOI-1233, a star burning 210 light years away that closely resembles our own sun that looked to be orbited by four or more planets.

To confirm that they had indeed discovered planets, the researchers had to rule out alternative explanations for a dip in light. For instance, in the case of eclipsing binary stars, a transiting star might create a threshold-crossing event that looks deceptively like the transit of a planet, Pinglé notes.

After months of study and careful observation, the researchers were able to confirm the presence of four exoplanets revolving around the bright star, also known by its official name, HD 108236. A fifth planet was recently discovered by a separate team of astronomers, making for a “unique” five-planetary system, Daysan says.

Of the five, the innermost planet most closely resembles Earth, Wright says. The hot, rocky planet is about 60 percent larger than Earth and orbits TOI-1233 about every four days.

The three other planets that they discovered are known as “sub-Neptune” planets, composed of rocky cores surrounded by a thick layer of hydrogen-helium gases. Similar in size to our own Neptune, the planets take between 6 and 19.5 days to complete their orbit around the star.

Coding in Python and parsing data about stellar temperatures and planet radii can be challenging, and most students face a steep learning curve at the beginning of their work, Sousa-Silva says. “I learned a lot more about coding in this project than I ever would have in class,” Wright says with a laugh.

And if they ever had a question, the students were welcome to ask their mentor—or the scholars working down the hall—for help. For a while, Sousa-Silva notes, the students were meeting with Daylan in the office next door to the visiting scholar Didier Queloz, who had won the Nobel Prize in Physics just a few months before.

Daylan has mentored a number of undergraduates and high schoolers over the years, but Wright and Pinglé will be among the first of his mentees to publish research. “I really like working with high school students because they have minimal bias. They have not been taught to think in a particular way,” he says.

“[The students] are so good at finding things that may skip your eyes, basically. It’s fun. And I really like the exchange of ideas,” Daylan adds.

Now that their findings have finally published, Pinglé says he’ll take this semester to focus on taking the S.A.T. He’ll also need to decide where to apply for undergrad, where he plans to study applied mathematics. He mentions Harvard, MIT or Caltech as among his top choices.

Next fall, Wright will move to Scotland to embark on a five-year Master’s in Astrophysics at the University of Edinburgh, after which she hopes to complete a PhD in astrophysics. She’s been captivated with space ever since she learned about moon phases in school as a seven-year-old. “I think what excites me most [about astrophysics] is that there’s just endless discoveries to be made. There’s no limit—you will constantly be learning new things,” Wright says.

But it wasn’t until high school that Wright realized her skill for math and physics and began to consider a career in space research.

“I just fell in love with it,” she says. “And I started to realize that I can make a career out of this.”