By Terrance Turner
NASA mathematician Katherine Johnson, whose work made American space travel possible, died Tuesday at the age of 101. Johnson broke both racial and gender barriers over the course of her career. But she also made game-changing calculations that helped the U.S. achieve President Kennedy’s promise of landing a man on the moon. Only belatedly did she earn the credit and praise that she deserved.
She was born Creola Katherine Coleman on August 26, 1918 in White Sulphur Springs, West Virginia. She was the youngest of four children. She had an early interest in math: “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,” NASA quoted her as saying. “I couldn’t wait to get to high school to take algebra and geometry,” Mrs. Johnson told The Associated Press in 1999. But according to the New York Times, her hometown’s segregated school system only allowed black children to go up to the sixth grade. So every fall, her father moved the family 125 miles away to Institute, West Virginia. There, Katherine and her siblings attended the West Virginia Collegiate Institute, which is now West Virginia State University, per the Times.
Katherine began high school at 10 (!) and graduated at age 14. Then she entered West Virginia State, where she took every available math class available by her junior year. She graduated summa cum laude in 1937 with a double major in mathematics and French. She then took a job as a teacher. But she left that job when she (and two men) became the first black students to integrate West Virginia University in 1940.
By this point, Katherine had married James Francis Goble, a chemistry teacher. The new Mrs. Goble left the university when she realized she was pregnant with her first child. In 1941, President Franklin Roosevelt issued Executive Order 8802, banning discrimination in the defense industry. In 1943, the Langley laboratory — established by the National Advisory Committee for Aeronautics, or NACA — began advertising for black women trained in mathematics.
For most of the 1940s, Mrs. Goble served as a stay-at-home mother to her three daughters. She later returned to teaching. But in 1952, she heard that Langley was looking for black female mathematicians. She applied for the job and was eventually hired. She joined the West Area Computing Unit, to which black women were regulated. That branch was run by fellow mathematician Dorothy Vaughan.
Before electronic computers, Johnson was one of several black female mathematicians — or, as she memorably put it, “computers who wore skirts”. The facility was initially segregated by race and gender, but by the time she joined, the kitchens had already been integrated. Bathrooms were still segregated, but white ones were unmarked. Mrs. Goble unwittingly integrated those bathrooms by using them before she knew they were for whites, according to the Times. No one reprimanded her, and she continued.
She joined NACA in June 1953. Two weeks into her tenure, the Flight Research Division asked to borrow Goble. She helped calculate aerodynamics of airplanes. But according to NASA’s website, Mrs. Goble also analyzed data flight tests and investigated a plane crash. While she was finishing this work, her husband died of brain cancer in December 1956.
The Soviet launch of Sputnik in 1957 launched a competition between America and Russia to explore space. The next year, NACA became NASA and essentially desegregated. Katherine became part of the “Space Task Group”, taksed with getting NASA into space. The next year, she married US. Army Captain James A. Johnson. They would remain married until his death in 2019.
So it was as Katherine Johnson that she co-authored a 1960 report “Determination of Azimuth Angle at Burnout,” which describes the complex equations needed for orbital spaceflight. Mrs. Johnson became the first woman in the NASA flight division credited as author on a research report. Some of her calculations are shown below.
Her responsibilities came to revolve around flight trajectory — the path of a flying projectile, such as a rocket. In her autobiography, Reaching for the Moon, Johnson recalled: “I knew from my college studies that the rocket’s trajectory into space would be in the shape of a parabola, a plane curve that is identical on both sides and shaped roughly like the letter U. (In this case, our parabola would look like a upside-down U.) The fact that both sides are identical made it fairly easy for me to predict where the capsule would be at any particular point in time. To retrieve the astronaut safely, we had to make sure that we understood the exact place and time that space capsule would touch down.”
“For an orbiting object to land at a specific location on Earth at a specific time, it has to be navigated to a precise point in outer space. That point, called azimuth, is where the process of bringing the spacecraft down to the landing point would begin,” she explained. Johnson went on to explain that the 1960 report “determined the azimuth angle — the angle of the capsule’s velocity — at the precise moment when the astronaut flying the capsule would turn its rockets off. At that point, the force of gravity would take over and the capsule would free-fall down to the landing point.”
In 1961, Johnson calculated the trajectory for the flight of Alan Shepard, the first American in space. According to Forbes, Johnson did the calculations entirely by hand. It was her calculations that helped recovery crews find Shepard when his capsule landed in the Atlantic Ocean. In 1962, Johnson verified the trajectory for John Glenn, the first American to orbit the Earth. Those calculations were done by an IBM computer, but Glenn didn’t trust them. Glenn asked that Johnson to double-check the numbers on her desktop calculator: “If she says they’re good, then I’m ready to go.” Johnson re-calculated everything by hand: the numbers matched, and the mission was successful.
In 1969, Johnson calculated the trajectory for Apollo 11, the historic moon landing. Her math helped coordinate the lunar module and command module in orbit. And in 1970, it was her calculations that saved the Apollo 13 crew. According to NASA, “oxygen tank No. 2 blew up, causing the No. 1 tank to also fail. The command module’s normal supply of electricity, light and water was lost, and they were about 200,000 miles from Earth.” 210,000 miles, to be exact. To survive, the crew had to get in the lunar module, using it as a “lifeboat” to save what was left of the command module’s oxygen supply. From there, they had to make a loop around the Moon to put themselves back on track to return to Earth.
Johnson was prepared for that. Forbes recalls: “Every time Johnson worked on a space mission, she calculated backup trajectories, which would get the crew home if an emergency disrupted the original flight plan. She also devised backup navigation charts; if a spacecraft’s electronic navigation systems failed, astronauts could manually take sightings of a single star to find their way home again. The Apollo 13 crew used Johnson’s charts and backup trajectories to get home.”
Johnson contributed to the Space Shuttle program, which began in 1972 and eventually launched the Columbia in 1981. After 33 years at Langley, she retired in 1986. But she remained active, playing bridge and spending time with family and friends. According to the Daily Press, Johnson kept occupied even into her nineties: “Johnson continued to live on the Peninsula and remain active, singing in the choir at Carver Memorial Presbyterian Church. She was learning to speak Spanish at age 98 and still playing bridge at 99.”
In 2015, President Barack Obama honored Johnson with the Presidential Medal of Freedom. The next year, author Margot Lee Shetterly detailed the stories of Johnson and other female “computers” in her book Hidden Figures: The American Dream and the Untold Story of the Black Women Who Helped Win the Space Race. The book was made into a film, where Johnson was played by actress Taraji P. Henson. The film was nominated for the Academy Award for Best Picture (the highest-grossing nominated film). And when Johnson appeared with the film’s stars at the Oscars, she received a standing ovation.
Johnson is survived by two of her daughters, six grandchildren, and many more great-grandchildren. Of course, the work that she did — and the history-altering missions to which she contributed — will live on forever.