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Katherine Johnson: Pioneering NASA mathematician

Katherine G. Johnson
Katherine G. Johnson was a NASA mathematician who helped send the first Americans into space and the first astronauts into space. She is one of the most celebrated black women in space science. (Image credit: Bob Nye/NASA)

Katherine Johnson was a NASA mathematician who played a key role in numerous NASA missions during the Space Race, perhaps most notably calculating the trajectory needed to get the Apollo 11 mission to the moon and back. As a black woman working for NASA in the 1950s and '60s, Johnson overcame social boundaries and racial discrimination. Her impressive career was the subject of the 2016 book and movie "Hidden Figures." 

Related: How 'Hidden Figures' came together: Interview with author Margot Shetterly

Johnson's road to NASA

Johnson was born in 1918 in White Sulphur Springs, West Virginia, the youngest of four children. From a very young age, she had a fascination with numbers, which would lead her to defy all expectations throughout her life. "I counted everything. I counted the steps to the road, the steps up to church, the number of dishes and silverware I washed … anything that could be counted, I did," Johnson said in an interview with NASA in 2015. 

Johnson's hometown did not offer public schooling for black children past eighth grade, so her family moved 120 miles (193 kilometers) away so that she could attend high school. She graduated high school at just 14 and college at 18, securing degrees in both mathematics and French from the historically black West Virginia State College. 

While in school, her potential was clear to her teachers. One of her professors, William Schieffelin Claytor, encouraged Johnson to become a research mathematician and created a geometry class just for her. After teaching for a few years, Johnson was accepted to West Virginia University's graduate math program, and in 1939, she became the first black woman to attend the school. 

A year into her coursework, she left to raise her three daughters. Then, in 1952, a relative told her about an exciting new opportunity: The National Advisory Committee for Aeronautics (NACA), the predecessor to NASA, was hiring black women to solve math problems. Johnson applied right away. She was soon hired as a "computer" at the Langley Research Center, tasked with performing and checking calculations for flight tests.

In addition to excelling at her work, Johnson was exceptionally curious and assertive, always questioning her colleagues and asking to be included in important meetings. When she started at NACA, Johnson and her black colleagues were required to work, eat and use restrooms separately from the white employees. But Johnson ignored the racial and gender barriers of the time and became the first woman in the Flight Research Division to be credited as an author on a research report.

Sending astronauts into space and to the moon

In 1958, NACA became NASA, and the Space Race began. Johnson's passion was geometry, which was useful for calculating the trajectories of spacecraft. For NASA's 1961 Mercury mission, she knew that the trajectory would be a parabola, a type of symmetrical curve. So when NASA wanted the capsule to come down at a certain place, she was not deterred. 

"You tell me when you want it and where you want it to land, and I'll do it backwards and tell you when to take off," Johnson said. Subsequent orbital missions were more complicated, with more variables involving the position and rotation of the Earth, so Johnson used a celestial training device to perform her calculations.

Johnson was tasked with calculating the trajectory for Alan Shepard's historic flight, during which he became the first American to reach space. She also confirmed the trajectory to send the first American into orbit around the Earth. By this time, NASA had begun using electronic computers to perform these tasks, but the machines could be a little temperamental. Before his Friendship 7 mission, astronaut John Glenn requested that Johnson personally recheck the calculations by hand. "If she says they're good, then I'm ready to go," Glenn said.

The next challenge was to send humans to the moon, and Johnson's calculations helped sync the Apollo 11 lunar lander with the moon-orbiting command and service module to get the astronauts back to Earth. She also proved invaluable on the Apollo 13 mission, providing backup procedures that helped ensure the crew's safe return after their craft malfunctioned. She later helped to develop the space shuttle program and Earth resources satellite, and she co-authored 26 research reports before retiring in 1986.

Katherine Johnson, pictured here at NASA's Langley Research Center, where she worked as a computer and mathematician from 1953 to 1986.  (Image credit: NASA)
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Johnson's legacy

Johnson spent the following years speaking to students about her extraordinary career, encouraging them to pursue STEM education. "Some things will drop out of the public eye and will go away," she said. "There will always be science, engineering and technology. And there will always, always be mathematics. Everything is physics and math."

She and her colleagues became famous with the publication of "Hidden Figures" (William Morrow and Co., 2016) by Margot Lee Shetterly and the release of the blockbuster movie of the same name, which starred Taraji P. Henson, Janelle Monáe and Octavia Spencer as Johnson and her colleagues Mary Jackson and Dorothy Vaughan. The release of "Hidden Figures" made Johnson one of the most celebrated black women in space science and a hero for those calling for action against sexism and racism in science and engineering.

In 2015, President Barack Obama awarded Johnson the Presidential Medal of Freedom, America's highest civilian honor. And in 2016, the NASA Langley facility at which Johnson worked renamed a building in her honor: the Katherine G. Johnson Computational Research Facility. 

In 2019, Johnson told her own story for young readers in a book called "Reaching for the Moon" (Atheneum Books for Young Readers).

"Every time engineers would hand me their equations to evaluate, I would do more than what they'd asked. I'd try to think beyond their equations. To ensure that I'd get the answer right, I needed to understand the thinking behind their choices and decisions," she wrote.

"I didn't allow their side-eyes and annoyed looks to intimidate or stop me. I also would persist even if I thought I was being ignored. If I encountered something I didn't understand, I'd just ask. … I just ignored the social customs that told me to stay in my place."

Related: Reaching for the Moon: Exclusive excerpt from Katherine Johnson Autobiography for kids

Johnson died Feb. 24, 2020, at age 101. NASA Administrator Jim Bridenstine announced her death and promised that her legacy would be remembered.

"At NASA, we will never forget her courage and leadership and the milestones we could not have reached without her," Bridenstine said. "We will continue building on her legacy."

Additional resources:

This article was adapted from a previous version published in How It Works magazine, a Future Ltd. publication. 

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