Read & Think · People Who Dared

The Numbers He Trusted

Katherine Johnson did the math by hand that sent Americans into space and to the Moon.

Name

Date

Katherine Johnson working at her desk at NASA Langley in 1966, with a globe beside her. — Katherine Johnson at her desk at NASA Langley in 1966 — the years when her hand-checked numbers cleared John Glenn to circle the Earth and helped aim Apollo at the Moon. Photo: NASA, 1966, public domain (scan restored by Adam Cuerden, via Wikimedia Commons).

In 1962, an astronaut named John Glenn was about to become the first American to circle the Earth. A new electronic machine had worked out his flight path. Glenn did not fully trust it. He asked for one person to check the numbers by hand: a Black woman named Katherine Johnson. If she said the numbers were good, he told them, he was ready to go.

Katherine was born in 1918 in West Virginia. She loved to count. She counted steps, dishes, and stars. School could not keep up with her. She skipped grades, and by fifteen she was in college. She finished at eighteen with degrees in math and French.

In those days, the law kept Black students and white students apart. That was called segregation. In 1939 Katherine was one of the first three Black students chosen to enter the graduate school at West Virginia University. Doors were opening, but only a crack.

In 1953 she took a job at a lab in Langley, Virginia. The lab belonged to the group that later became NASA. Her job title was "computer." Back then a computer was a person who did math by hand, all day, with a pencil. The Black women computers worked in a separate room from the white ones. Katherine's work was so sharp that engineers pulled her into their meetings, where women were not usually allowed.

In 1961 she worked out the flight path for Alan Shepard, the first American in space. Then came Glenn's flight around the Earth. Katherine checked the machine's numbers, one by one. They matched. Glenn flew, and he came home.

She kept going. Her math helped send Apollo 11 to the Moon in 1969. When Apollo 13 broke down in space, her backup charts helped bring the crew home alive.

For most of her life, few people knew her name. In 2015, at ninety-seven, she received the Presidential Medal of Freedom, the highest honor a civilian can get. A movie called Hidden Figures told her story the next year. NASA named a building after her. Katherine Johnson died in 2020, at 101 — a woman who counted everything, and whose numbers took people to the Moon and back.

Source: Facts drawn from NASA's published histories and the public record; photo credited on the page.

The Numbers He TrustedComprehension

Check that you read it

Fill each blank with the right word from the box.

Word bank: computer · Glenn · Langley · Apollo · Freedom

Katherine's job title at the lab was " computer," which in those days meant a person who did math by hand.
Before his flight around the Earth, astronaut John Glenn asked for Katherine to check the machine's numbers.
In 1953 Katherine started work at a lab in Langley, Virginia.
Her math helped send Apollo 11 to the Moon in 1969.
In 2015 she received the Presidential Medal of Freedom.

Choose the best answer

Why did John Glenn ask for Katherine to check the numbers?
- A. He did not know how to read them himself
- B. He trusted her math more than the new machine
- C. The machine had stopped working
- D. NASA rules said a woman had to sign off
What did the word "computer" mean when Katherine was hired?
- A. A machine that did math
- B. A person who did math by hand
- C. A rocket engineer
- D. A room full of typewriters
What does Katherine's story show about talent and fairness?
- A. Talent always gets noticed right away
- B. Rules kept her out, but her work was too good to ignore
- C. She succeeded because the rules were fair to everyone
- D. Math was easy for everyone in her lab

The Numbers He TrustedVocabulary

Word cross

Use what you read to fill the puzzle. Every clue is answered somewhere in the article.

1L

2C

3N

A

S

A

4M

O

N

M

5G

G

6S

7A

P

O

L

O

L

H

U

E

8S

E

G

R

E

G

A

T

I

O

N

Y

P

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N

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9M

E

D

A

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Across

The space agency her lab became part of.
Where Apollo 11 went in 1969.
The Moon program her math helped.
The law that kept Black and white students apart.
She received the Presidential ___ of Freedom in 2015.

Down

The Virginia town where her lab was.
Katherine's job title — back then, a person, not a machine.
The astronaut who wanted her to check the numbers before he flew.
The first American in space; she worked out his flight path.

The Numbers He TrustedCritical Thinking

Now think

There isn't one right answer here. Explain your thinking — the reasons matter more than the answer.

1 · Katherine's work was "too good to ignore." Find two moments in the story where her skill opened a door that was supposed to be closed, and explain what each one shows.

For the teacherA strong answer names specific moments — being chosen for the graduate school in 1939, engineers pulling her into meetings women were not allowed in, Glenn asking for her by name — and says what each shows about skill pushing against unfair rules, rather than just repeating that she was smart.

2 · John Glenn had a brand-new machine to do the math. Why do you think he still wanted a person to check it? What does that tell you about trust and new technology?

For the teacherA strong answer reasons about cause and effect: the machine was new and unproven, while Katherine had a track record he had seen, so trust went to the one with the record. Good answers connect this to how people decide whether to trust new tools today.

3 · For most of her life, almost no one knew Katherine's name. Does it matter whether the people who do important work get credit for it? Why or why not?

For the teacherA strong answer takes a position and weighs real trade-offs — fairness to the person, whether credit changes the work itself, and how missing names change the history we learn — without a single correct answer being required.