Fisher was pregnant when NASA told her they wanted to send her to space.
"I wasn't about to say no," she told The Washington Post.
After giving birth to her daughter and completing 14 months of intense training, Fisher went to space on a seven-day, 23-hour mission on the space shuttle Discovery in 1984. She was the first mother in space.
After the Challenger explosion grounded NASA's shuttle program, she took a leave of absence and returned in 1996 as chief of the space station branch. She retired in 2017.