Creola Katherine Johnson was an American human computer whose calculations of orbital mechanics as a NASA employee were critical to the success of the first and subsequent U.S. crewed spaceflights. During her 33-year career at NASA and its predecessor, the National Advisory Committee for Aeronautics, she earned a reputation for mastering complex manual calculations and helped pioneer the use of computers to perform tasks previously requiring humans. The space agency noted her "historical role as one of the first African-American women to work as a NASA scientist".
Johnson's work included calculating trajectories, launch windows, and emergency return paths for Project Mercury spaceflights, including those for astronauts Alan Shepard, the first American in space, and John Glenn, the first American in orbit, and rendezvous paths for the Apollo Lunar Module and command module on flights to the Moon. Her calculations were also essential to the beginning of the Space Shuttle program, and she worked on plans for a human mission to Mars.
In 2015, President Barack Obama awarded Johnson the Presidential Medal of Freedom.