Stepping outside of her tent in the middle of the night, Sara Seager saw the stars for what she felt like was the first time. She was only 10, but that camping trip with her father in Ontario in the early 1980s made her wonder: What else was out there in that dark sky?

“I just remember seeing the stars and being overwhelmed by the beauty and the vastness and the mysteriousness of it,” she said in an interview with The Washington Post. “There’s something almost terrifying about it at the same time as it being so beautiful, because yeah, it’s so unknown, and it seems like it goes on forever.”

Decades removed from that first look at the stars, Seager, 49, is among the world’s leading astronomers in studying thousands of exoplanets, or worlds that belong to other stars. The rise of exoplanets is of specific interest for astronomers and NASA months ahead of the scheduled launch of the James Webb Space Telescope, the 30-year, $8.8 billion project that promises to tell us more about what might exist in the stars and galaxies that have long remained mysteries.

The search for life beyond Earth is featured in the documentary “The Hunt for Planet B,” which premieres this week at South by Southwest’s virtual film festival. Directed by Nathaniel Kahn, the film also looks at a new wave of astronomers focusing on exoplanets that are helping spearhead discoveries about the stars — an area that’s predominantly led by women.

“It’s the next big thing,” Seager, a planetary expert at the Massachusetts Institute of Technology, said of the anticipation in the astronomy community surrounding the Webb.

Nearly three times larger and 100 times more powerful than its predecessor, the Hubble Space Telescope, the Webb is scheduled to be launched on an Ariane 5 rocket from French Guinea on Oct. 31 and head to a point 1 million miles from Earth, or four times the distance to the moon. It comes after a long series of mishaps and budget crises nearly derailed NASA’s biggest robotic science project — and that was before Congress threatened to cancel it altogether.

Yet, as the Webb completed its final functional tests last month at the Northrop Grumman facility in Redondo Beach, Calif., the missteps of the past meant little looking up at the machine — a gold-plated device resembling an oversized sunflower — that could help shed new light on questions long left unanswered. (That is, if pirates don’t get to it first.)

“I wanted to capture this incredible telescope coming together, which really is addressing the biggest questions that have haunted us since the beginning of time,” Kahn told The Washington Post. “Where do we come from? How did the universe begin? And, the biggie, are we alone?”

Premiering about seven months before the launch of the Webb, the film focuses on not just the telescope but the study of exoplanets and the female astronomers and scientists who have championed a field once considered too fringe and risky and still thought of as relatively new.

Seager remembers the field being born about 25 years ago when the first exoplanet was discovered around a star like the sun in 1995. At the annual conference of the International Astronomical Union, Seager saw how the cosmology part of the session was much more of a mature science populated with, as she puts it, “all men with white hair.” But when she walked over to another part of the conference focused on exoplanets, she noticed it was all young people, and mostly women, willing to take a chance on a new field largely ignored by many.

“I feel like then women could get a foothold, and women like me, like others you’ve seen in the film, were able to move up,” she said, emphasizing that older, White men still largely dominate leadership positions in astronomy. “And then we could be role models for others.”

The study of exoplanets exploded after the Kepler Space Telescope launched in 2009 to detect the worlds that belong to other stars. Since then, the Kepler has found thousands of exoplanets that will be observed by the Webb — an achievement in a field with many of its leaders now being women.

“By being able to show that these teams of women are learning to work together and are finding that they can move much more quickly and be much more effective, they are changing the world by banding together and shifting an entire paradigm of how science is done and thought about,” Kahn said.

The film features women from all parts of astronomy, from an engineer on the Webb to the leaders of the Kepler. Among that group is Jill Tarter, chair emeritus of the SETI Institute and a legend among those dedicated to searching for extraterrestrial civilizations. At one point in the documentary, Tarter, who was the inspiration for Jodie Foster’s character in the 1997 film “Contact,” is asked by Kahn whether she thinks life exists and if it will be discovered.

“It doesn’t matter what I think,” she replied. “We’re not doing religion here, we’re doing science.”

In an interview with The Post, Tarter, 77, said that while the Webb is an important step in cosmic observation, the public should not expect to receive significant answers, if any, as to whether other life could exist. Instead, she’s more interested in the information the Webb might give that no one anticipates.

“Astronomy has a very old and rich history that we build new instrumentation and we go and argue for funding for that instrumentation, telling our funders all of the answers it’s going to find to questions that we have today,” Tarter said.

“But the true history of astronomical instrumentation is when you build an instrument to look at the cosmos in a different way, the most exciting thing that instrument does is discover something you never expected. So I hope that Webb will continue with that legacy and will show us something that none of us had in mind when the telescope was proposed.”

For Seager, the launch of the Webb, and the chance to observe the exoplanets with the space telescope, is personal. Before her husband, Michael Wevrick, died of cancer in 2011, Seager vowed to her spouse that she would do “big things” and that his death would have meaning. In the film, she recalled that when she said this to him, the 47-year-old Wevrick, who could barely speak at the time, offered a simple reply: “You would have done it anyway.”

A decade later, Seager joins astronomers in anticipation of the Webb’s long-awaited launch. Like Tarter, she said that while the telescope will revolutionize what we can know about the cosmos, scientists and researchers might not find what they’re looking for.

That’s okay, said Seager, who recalled a friend saying she had two choices after her husband died: crumble or keep moving toward her dream. She chose the latter, unable to shake the feeling she had the first time she looked up at the stars all those years ago.

“It’s not that I have to find an Earth and name it after [Wevrick],” she said in the film. “It’s about making a difference and doing something with meaning.”