#### Katherine Johnson, NASA Mathematician

Katherine Johnson talks about her early affinity for mathematics, a college professor who noticed her gift and pushed her to pursue advanced math courses and how she eventually became a NASA mathematician who calculated, among many other computations, the trajectory for the space flight of Alan Shepard, the first American in space.

## Katherine Johnson

#### NASA Mathematician

Katherine Johnson talks about her early affinity for mathematics, a college professor who noticed her gift and pushed her to pursue advanced math courses and how she eventually became a NASA mathematician who calculated, among many other computations, the trajectory for the space flight of Alan Shepard, the first American in space; John Glenn, the first American to orbit earth; and Apollo 11, the first human mission to the moon.

KATHERINE JOHNSON: Math. It's just there. It has always been a part of whatever I was doing.

- All engines running.

KATHERINE JOHNSON: You're either right or you're wrong. That I liked about it.

[MUSIC PLAYING]

They tell me I counted everything. Everybody studied at a big table, and after I finished mine, I helped them get theirs. And I was the youngest. I wound up ahead of my brother, maybe two grades. I don't remember how many. I entered college. I was 15. I was gonna be a math teacher because that was it. You could be a nurse or a teacher.

[MUSIC PLAYING]

He said, you'd make a good research mathematician. I said, oh? What do they do? He said, you'll find out. So he had me take all the courses in the catalog. Sometimes I was the only person in the course. I said, where will I find a job? He said, you'll look till you find it. Took me seven years, but I found it.

[MUSIC PLAYING]

He said, you're very lucky. Langley has a post for black mathematicians, just opened it up to women. They had a pool of women mathematicians. They just wanted somebody to do all the little stuff, while they did the thinking. We were called computers, women computers. I had been there less than a week, when this engineer came in and wanted two women computers, and Mrs. Vaughn sent me over to the flight branch. And we never went back.

[MUSIC PLAYING]

- Today, a new moon is in the sky, placed in orbit by a Russian rocket.

KATHERINE JOHNSON: Oh, they felt terrible that, here we sat, and the Russians had a vehicle riding around, looking down on you. So we set out to send somebody up there and look down to. They'd called up a group of engineers and have a briefing as to what they were gonna have to do. And I asked, could I go? They said, women don't ever go to those. I said, is there a law against it? They said, no, well, let her go ahead. I wanted to know what it was they were looking for. So I wound up doing what it was they were trying to find out.

[MUSIC PLAYING]

- Commander Alan B. Shepard was to become the first man sent into sub-orbital flight. The Mercury capsule is right on course.

KATHERINE JOHNSON: Our office computed every mission that went out at that time-- the height, the speed, and so on. It became a geometry problem.

- Ignition sequence start.

KATHERINE JOHNSON: I felt most proud of the success of the Apollo mission.

- Zero. All engines running--

KATHERINE JOHNSON: They were going to the moon.

- We have a lift off.

KATHERINE JOHNSON: I computed the path that would get you there. You determined where you were on Earth when you started out, and where the moon would be at a given time. We told them how fast they would be going, and the moon will be there by the time you got there.

[BEEP]

- Beautiful, just beautiful.

KATHERINE JOHNSON: We were really concerned when they were leaving the moon, going back. He had two adjusters, we said. If he'd missed it by a degree, he doesn't get into orbit. I was looking at the television. I said, boy, I hope he's got that right.

[LAUGHING]

And I was sitting there hoping I'm right, too.

[LAUGHING]

[MUSIC PLAYING]

John Glenn said, tell her. He knew that I was the only woman that worked on it. He said, if she comes up with the same answer that they have, then the computer's right. It took me a day and a half to compute what the computer had given them. Turned out to be the exact numbers that they had.

[MUSIC PLAYING]

It was my job. And I did my job correctly and well.

[MUSIC PLAYING]

- We used old books to give the position of the moon at a given time. And then we knew the position of the earth. So we would, in our minds, construct a plane. And mathematically, you determined where you were on earth when you started out, and where the moon would be at a given time. And then you computed the path that would get you from here to there. And the moon would be there by the time you got there.

- John Glenn was just preparing to go up and orbit. At all times, he knowed his speed and his altitude and we know it, having calculated where he should be at a given time. And we'd tell him at what point he will begin his descent, so that at a given time you tell him to descend with mathematical equations. And if he descends the way you tell him, he'll hit the water when you tell him. He had confidence in what we had computed for him and he had to do it just as we said.

- We were really concerned when they were leaving the moon, going back. That was the part that I worried about, that they should be exactly correct on that. And I was sitting there hoping I'm right too. It's a logical thing, you miss a train, you wait for the next train. Ain't no more trains. So, I was just sitting there seeing it take off and hoping he made it.

- The whole flock of the astronauts came over to our office because our boss was a sailor and knew the stars well. We were doing some studies on the positions among the stars, but now, he said we can't figure out one constellation from another. When you are up there among the stars, you can't pick out the constellations.

- I was majoring in math and French, and I got a degree in math and French, and I didn't fully decide which I was gonna work on until one day I was walking across campus and this lady said to me, "I'm back." She had been fired. This was during the Depression, and women, married women, were asked not to work so that the men would have work. So she was back teaching math, and she was tough. And she said, "I'm back teaching math, and if you're not in "my class the first of the semester, "I'm gonna come find you." And she meant it. She said, "I've gotta have Katherine." So they put me in her class, because she knew she was tough, and she was. She was very good.

- My mother had been a teacher. She was a born teacher; she was good at it. If I was home alone, my mother was there. I had to be doing something, so I was reading, I understand, when I was four. And teacher was visiting and she was, but anyway, I said, "Missjust, "you can just stop spelling 'cause I can spell," so she was so excited, she started a little summer school. When I got to school, then they just let me go onto the second grade.

- Langley has a post for black mathematicians. Just opened it up to women. So I applied for a job, one of those jobs. So they said we'll hold this job for you a year if you can wait. We've filled our quota for this year. So I said, no problem. Said I'll come back next year. So took the children went down. I subbed for a year and he became a painter in the shipyard. And we were happy.