Katherine Johnson

Continued from above

And when Neil Armstrong's first small steps on the Moon became a giant leap for mankind in July 1969, Johnson helped put him there.

Johnson, a research mathematician and scientist at NASA's Langley Research Center in Hampton, calculated the trajectories for the missions that have made America the dominant power in space. In a 33-year career with NASA that pre-dated the Mercury project and ended with the initial phase of the space shuttle, she worked out the intricacies of interplanetary trajectories, space navigation and the orbits of spacecraft.

Blacks in Science and Medicine by Vivian Ovelton Black Contributors to Science and Technology U.S. Department of Energy

Now 78 and retired, Johnson did her early work with pencil and paper.

''It was a time when computers wore skirts,'' Johnson said.

She started at Langley in June 1953 as a pool mathematician. The pools, which were racially segregated, were made up of women. She was ''loaned'' to flight research, the nucleus of the space program, and stayed there.

Working on Shepard's flight was easy, she said. ''It was just a matter of shooting him up and having him come back down,'' she said of his flight path. Of course, the calculations had to put his splash-down into the ocean and not on land.

But the basics were the same -- mathematics.

''You do it all with algebraic equations -- thousands and thousands of algebraic equations,'' said Johnson. ''All the time you have to remember that the Earth is rotating and the moon is moving. That figures into it.''

In readying for the historic first walk on the moon, she calculated the trajectories to put a spacecraft into a lunar orbit, to send a lunar landing module to the moon's surface, to return it to the spacecraft and to get the spacecraft back to Earth.

She also developed emergency navigation systems for the early astronauts. She mapped exactly what stars the astronauts should see at each point in their orbit through the tiny windows in their spacecraft.

The charts were like a stellar roadmap for the astronauts, so that should their on-board navigation systems fail, or should they lose contact with Mission Control, they could tell whether they were still on course.

She was recognized by NASA with special achievement awards in 1970, 1980 and 1985.

Born in White Sulphur Springs, W.Va., Johnson was the youngest of four children in a family that valued education. At the time, White Sulphur Springs had no school for blacks that went beyond the eighth grade. For eight years, her family would pack up each September and move 120 miles, to Institute, W.Va., so Johnson and her siblings could finish high school and college.

At West Virginia State College, Johnson earned a degree in French and mathematics, graduating summa cum laude in 1937.

She taught high school and elementary school in Southwest Virginia before moving to Hampton and working for NASA.

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