Liftoff of the Mercury-Atlas 6 mission on Feb. 20, 1962. On this mission, John Glenn became the first American to orbit Earth. As part of the preflight checklist, Glenn asked engineers to get NASA research mathematician Katherine Johnson to check the orbital equations by hand on her desktop mechanical calculating machine.
Liftoff of the Mercury-Atlas 6 mission on Feb. 20, 1962. On this mission, John Glenn became the first American to orbit Earth. His Friendship 7 capsule launched aboard a Mercury-Atlas rocket, and during his almost five-hour flight he circled Earth three times before splashing down in the Atlantic 800 miles southeast of Bermuda.
The trajectory was controlled by computers but, as part of the preflight checklist, Glenn asked engineers to get NASA research mathematician Katherine Johnson to check the orbital equations by hand on her desktop mechanical calculating machine.
Image Credit: NASA