At MIT, Shields struggled academically at first and took refuge in the creative arts. She was chosen to participate in the Burchard Scholars Program, whose monthly dinner seminars bring faculty members together with students who excel in the arts, social sciences, and humanities. She sang in the a cappella group the Muses and performed in lots of plays. At the end of her senior year, she found herself wondering: “Do I go to grad school in acting or astronomy?”
“There were a lot of these things that seemed to be aligning—that were telling me: Go back and get that PhD.”
The latter won out, but not for long. Shields headed to a graduate program in astronomy at the University of Wisconsin–Madison. “During that year, I had a white male professor tell me to consider other career options, and that was hard to hear,” she says. She remembers thinking, “I’m going to the other dream because clearly someone’s telling me that I don’t belong here. Maybe they’re right.”
So she applied to UCLA, where she got an MFA in acting, leaving astronomy for more than a decade. But then, when Shields was working odd jobs to supplement her acting gigs, a mentor from her undergraduate years encouraged her to look on a Caltech-operated job website. She saw an opening for a help desk operator at the Spitzer Space Telescope, an infrared telescope that is particularly adept at viewing the formation of young stars—and it only required a bachelor’s degree. “I’d refer the harder questions to the PhDs,” she says. “But by taking that job, I got to go to astronomy talks again … This field of exoplanets had just exploded during the time I’d been away.”
Shields had some success in acting, including a part in a film called Nine Lives, which screened at the Sundance Film Festival. But a big break—and then heartbreak—came after she was cast as the host of the show Wired Science, only to lose the job when the producers decided to change presenters. It was a “devastating moment,” she says.
Soon after, she emailed the astrophysicist and science communications luminary Neil deGrasse Tyson, whom she’d been introduced to over email by an astronomer working with the Spitzer Space Telescope, and relayed what had happened. He replied that he’d seen her in the pilot and told her that “without a PhD you don’t have that street cred if you want to do science television,” she recalls. Meanwhile, she had applied to NASA’s astronaut candidate program but didn’t make it past the first level. (She did, however, get to play an astronaut in a recent Toyota ad.) “There were a lot of these things that seemed to be aligning—that were telling me: Go back and get that PhD,” she says. So she did, earning her doctorate in astronomy and astrobiology in 2014 from the University of Washington.
Astrobiology, Shields explains, is a relatively new field that studies the origin, evolution, and distribution of life in the universe: “It’s about how life got started on Earth.”
Astrobiologists might focus on the habitability of planets, or on methods for exploring life on other planets, or on liquids other than water that could support life. It’s a highly interdisciplinary field. “There are astronomers that are looking for these planets and are using their particular field of expertise to answer that question: Are we alone?” Shields explains. Some of them are “also chemists and biologists and oceanographers and geologists who tackle these questions from their own lens and specific area of expertise,” she says. “That’s why I love it. As an astrobiologist, we don’t have to get 15 PhDs. We get to collaborate with people in different departments who lend their own expertise … on those science questions.”
Shields is trying to answer a question sparked by the night sky—one that’s deeply personal yet universal in both the astronomical and the colloquial sense. “Ever since I was a little girl, I would look up at the sky and wonder what was out there,” she says. “It comes from a sense of wonder for me. I still have that feeling when I look up at the night sky and I see these little pinpoints of light. I wonder: Is there anyone looking back at me? … How far does space go?”