Roman was nicknamed "the mother of Hubble" for her work on the pioneering telescope, which launched in 1990. She joined NASA's headquarters office soon after the agency's founding in 1958. She was the first chief of astronomy, drawn to the offer of having the leeway to create such a pivotal department from scratch.
A previous astronomer, Lyman Spitzer, proposed exploring the idea of a space-based optical telescope in 1946, but the budget and technology required for such a project wasn't available. Roman began leading talks around the idea in 1960, three decades before the instrument finally flew. She also helped spearhead the Cosmic Background Explorer (COBE), another orbiting instrument. [Hubble in Pictures: Astronomers' Top Picks (Photos)]
"She made it possible to get early telescopes up [into space] to learn what needed to be learned," science historian Bob Zimmerman told Space.com in 2009. "As soon as that technology started to mature, she was pushing for the design work. Her hard-nosed nature helped get the telescope built."
Over the course of decades of observation, the Hubble Space Telescope has changed the way astronomers and science-aficionados alike see the universe around us with its stunning imagery.
But Roman's path to NASA leadership was full of the usual challenges. Although her mother took her outside during the long Michigan nights to point out constellations and watch the northern lights, teachers often dismissed her interest in math and science.
"I was told from the beginning that a woman could not be an astronomer," she said in a video released by NASA earlier this year. In high school, her guidance counselor was also unsupportive of her academic interests. "She looked down her nose at me and sneered, 'What lady would take mathematics instead of Latin?'"
She later earned a bachelor's in astronomy at Swarthmore College, then completed a Ph.D. at the University of Chicago, where her thesis advisor once ignored her for six months straight, Roman later said.
She was a decade out from her doctorate when she joined NASA. Roman retired from the agency in 1969. After her retirement, she regularly spoke out about the importance of making astronomy more equitable, and last year, she was immortalized in Lego's Women of NASA set.