Katherine Johnson

Alan Shepard became the second man and the first American to go to space when he piloted the Mercury-Redstone 3 mission into space on 5 May, 1961. John Glenn followed a few months later when on 20 Feb, 1962, he piloted the Mercury-Atlas 6 mission to three complete orbits around the Earth. These flights, among several others, were the necessary testing and training precursors to the Apollo moon-landing missions already in the planning stages. Apollo 11 was the culmination of years of work, when American astronauts Buzz Aldrin and Neil Armstrong became the first humans to set foot on the Moon on 20 July, 1969. What is the common thread between all three of these monumental events? Katherine Johnson.