The boundary broken by the Apollo 11 astronauts, when they became the first humans to walk on the Moon on July 20, 1969, is one of the most famous in history. But the Apollo program also saw other kinds of boundaries broken back on Earth.

For example, Frances “Poppy” Northcutt was the first woman to work in an operational support role in the Mission Control Center in Houston during the Apollo program.

There were a lot of women in computer programming roles at the time — as the 2016 movie Hidden Figures made clear — and Northcutt started out in one of those roles at NASA straight out of college in 1965, shortly after graduating from the University of Texas at Austin. She majored in math (a not-uncommon field for women at the time, as many became math teachers) and had taken a celestial mechanics course. Her title was “computress.”

“What a weird title this is,” she tells TIME she recalls thinking. “Not only do they think I’m a computer, but they think I’m a gendered computer.”

Northcutt did number-crunching for the Gemini program, the predecessor to the Apollo program, and then was promoted to a position on the technical staff a little over a year later. She was on the team that specialized in trans-earth injection, the maneuvers that put the spacecraft on course to return to Earth from lunar orbit. During missions including Apollo 8, Apollo 11 and Apollo 13, Northcutt sat in a staff support room that the directors in the general mission control room would call if they needed assistance. She was the only woman in her job at the time, though she notes that women served in many non-technical roles at NASA.

The men with whom she worked had to get used to a woman being in a room of engineers.

“I was sort of the trophy,” she says in the new PBS documentary Chasing the Moon, which airs this week for three nights starting Monday, and from which the clip above is taken. “I was blonde, I was young, I was thin, I wore the ladies fashion clothes.” Archival footage goes on to show Northcutt being asked during an interview whether it’s true that whenever she clocks in, as “a pretty girl wearing mini skirts,” the “mission grinds to a screeching halt.”

She tells TIME that, at one point, she could tell she was being watched at work and heard colleagues talking about what could be seen on one of the camera channels in their internal system. “Finally, at one point, I turned on that channel, and there was a camera that was just on me.”

What did she do when she saw that? “I just went, ‘O.K. Now I know.'”

While some people who worked at NASA tried to get a glimpse of the action in the control room during the Moon landing, Northcutt didn’t go into work during that time, waiting until her shift came around. She was focused on the Earth-bound part of the mission, so her part came later.

“Some people wanted to say they were in the control room. I felt it was more important to be rested to do my job,” she says. “If there are too many people around, it can be a distraction.”

Frances 'Poppy' Northcutt speaks with a NASA colleague in Houston, Texas, circa 1969. TRW/PhotoQuest—Getty Images

She used the media attention she got for a higher purpose.

“Well of course I was being used. My feeling was, you can play this both ways,” she says in the documentary. “The mere fact that a lot of women found out for the first time that there was a woman in mission control was a very big deal. I thought it was important that people understand that women can do these jobs — going into science, going into technology, doing something that’s not stereotypical.”

Reflecting on that time, she feels that while the cigar-smoking, male-dominated rooms of NASA in 1969 were something out of Mad Men, the sexism she faced was not as egregious as the abuse and harassment that has more recently sparked the #MeToo movement. “There was a lot of sexism, but less than what most women experienced,” she says. The life and death situation for the astronauts meant “you’re very focused on what you’re doing.”

Her political awakening was a process that started shortly after she started working for a company contracted by NASA, when she realized that her male colleagues were getting paid overtime and she wasn’t. As she was reading articles about the women’s rights movement, she saw a newspaper ad for the Aug. 26, 1970, Women’s Strike for Equality about a half-hour drive away in downtown Houston, and took the day off to participate in the demonstration. LIFE profiled her in its story about the protests, and she told the magazine that she didn’t consider herself one of the “screamers” in the women’s liberation movement, but that she felt her work was such that there should be no room for gender bias: “If you write a computer program, it either works or it doesn’t. There’s no opportunity for anyone to be subjective.”

That kind of national press attention made her even more of an activist.

“I became more conscious partly because of the attention I was getting as the first and only woman in my role in the Mission Control Center,” she says. “It increased my awareness of how limited women’s opportunities were. It was almost 1970, we’re at the brink of going to the Moon, and we still don’t have more women? I should have been the 100th.”

In the early ’70s, she was part of a small group of politically active women who worked at the space center and began what would be a successful push to improve health benefits for single women. She says the contracting company that she worked for was progressive for the times and made some changes without a lot of active resistance.

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And as national interest in the Moon waned, Northcutt’s interest in the national women’s-rights cause soared. After the Apollo program ended, she joined the Houston mayor’s office as a women’s advocate for the city. Learning about all the legal barriers women encountered inspired her to go to law school, and she became a prosecutor and then a criminal defense attorney, and worked on domestic violence and reproductive rights cases throughout her career. She is currently the president of the Texas chapter of the National Organization for Women. Revisiting her comments in LIFE, she says that remained the case her whole life: “I saw myself as a quiet person, and I still do. I’ve always tried to work within the system, I never wanted to burn my bra.”

But, though much has changed since the 1960s, gender equality in STEM fields remains a battlefield. Fifty years after Apollo 11, Northcutt’s experience as the only woman involved via an engineering team is still not surprising. What’s more surprising to Northcutt is how much media attention the 50th anniversary of Apollo 11 is getting, considering that the American space program has been “sort of an afterthought” in recent decades.

“I think we should go to the Moon again,” she says of efforts coming out of both the private sector and public sector. “It was a giant mistake to have stopped [going]. We didn’t fly all the Apollo missions. We’ve never explored different ways to orbit the Moon. It’s like exploring Earth’s equator, never getting into the northern or southern latitudes. That would not represent a complete exploration.”

Not to mention, she says, space exploration contributed to indispensable technologies we use every day, from cell phones to freeze-dried food. And, though she’s disappointed when exploration is motivated by one-upping other countries rather than the pursuit of knowledge, she acknowledges that the space race of that earlier era is looked back on as a time when Americans came together — and thinks a return to the Moon might have same power today.

“[In] ’68 and ’69, there was a lot of political protest, distrust in government. We have that today as well,” she says. “The space program was a bright spot in that environment. Maybe that’s why there’s nostalgia for a great achievement like Apollo 11. Do you see us doing any great achievement right now? I don’t.”

The American Experience documentary Chasing the Moon premieres Monday through Wednesday, on PBS.

Write to Olivia B. Waxman at olivia.waxman@time.com.