Johnson "was an American hero and her pioneering legacy will never be forgotten," NASA Administrator Jim Bridenstine wrote on Twitter.
Katherine Johnson, one of the history-making, barrier-breaking NASA mathematicians depicted in "Hidden Figures," died Monday, the administrator of NASA said.
She was 101.
"Johnson helped our nation enlarge the frontiers of space even as she made huge strides that also opened doors for women and people of color in the universal human quest to explore space," NASA Administrator Jim Bridenstine said in a statement.
In a tweet, he called Johnson "an American hero."
Johnson was portrayed by Taraji P. Henson in the Oscar-nominated 2016 film about trailblazing black women whose work at NASA was integral during the space race.
The film also stars Octavia Spencer as the mathematician Dorothy Vaughan and Janelle Monáe as the engineer Mary Jackson.
The work of the women altered the country's history but their names were largely unknown until the movie received acclaim. Jackson died in 2005, and Vaughan died in 2008.
Johnson began working at NASA's predecessor, the National Advisory Committee for Aeronautics (NACA) in 1953 at the Langley Laboratory in Virginia.
She said her greatest contribution to space exploration was making "the calculations that helped sync Project Apollo's Lunar Lander with the moon-orbiting Command and Service Module." In other words, helping to put men on the moon in 1969.
She was also the first woman in the Flight Research Division to receive credit as an author of a research report for her work with Ted Skopinski on detailing the equations describing an orbital spaceflight.
She did trajectory analysis for Alan Shepard's 1961 mission Freedom 7, which was America's first human spaceflight, according to NASA.
She was also known for work that greatly contributed to the first American orbital spaceflight, piloted by John Glenn.
The 1962 flight required the construction of a "worldwide communications network" linking tracking stations around the world to computers in Washington, D.C., Cape Canaveral and Bermuda.
But astronauts weren't keen on "putting their lives in the care of the electronic calculating machines, which were prone to hiccups and blackouts," according to NASA. So Glenn asked engineers to "get the girl," referring to Johnson, to run the computer equations by hand. "If she says they're good,'" Johnson remembered Glenn saying, "then I'm ready to go."
"Glenn's flight was a success, and marked a turning point in the competition between the United States and the Soviet Union in space," NASA says.
She also worked on both the space shuttle and the Earth Resources Satellite programs, in addition to authoring or coauthoring 26 research reports.
Johnson worked for NASA for more than three decades, retiring in 1986. "I loved going to work every single day," Johnson said at the time.
She was born in White Sulphur Springs, West Virginia, in 1918 and skipped several grades due to her "intense curiosity and brilliance with numbers," her NASA profile says. At 13, she was attending the high school located on the campus of the historically black West Virginia State College, and enrolled there for undergraduate studies at 18.
It was at West Virginia State that she found a mentor in Professor W. W. Schieffelin Claytor, the first African American to publish in a mathematical research journal and the third African American to earn a doctorate in mathematics.
After graduating in 1937 with the highest honors and degrees in mathematics and French, Johnson began teaching at a black public school in Virginia.
She also made history, before her NASA career, when she and two men became the first three black students to be offered admission to West Virginia University after the state "quietly" integrated its graduate schools in 1939, according to NASA.
Johnson enrolled in the graduate math program but left school after the first session to start a family with her husband, James Goble. The couple had three daughters, and she returned to teaching when they grew older.
In 1952, a relative told her about the position in the all-black West Area Computing section at NACA. She and Goble moved their family to Newport News, Virginia, to pursue the position. Johnson was placed on a temporary project, but her role quickly became permanent.
Goble died of Cancer in 1956. Johnson married Lieutenant Colonel James Johnson in 1959.
President Barack Obama awarded Johnson the Presidential Medal of Freedom, America's highest civilian honor, in 2015.
West Virginia State University has commemorated Johnson's accomplishments with a bronze statue on campus and a scholarship in her name.
And last July, when Johnson was 100, a ribbon cutting ceremony was held when a NASA facility in West Virginia was reintroduced as the Katherine Johnson Independent Verification and Validation Facility.