A new film, Hidden Figures, tells the story of the maths wizards who Nasa relied on. When John Glenn was waiting to be fired into orbit aboard Friendship 7 in 1962, there was one person he trusted with the complex trajectory calculations required to bring him down safely from his orbital spaceflight: Katherine Johnson, an African-American mathematician who worked in Nasa’s segregated west area computers division. “Get the girl, check the numbers,” Glenn said before boarding the rocket. “If she says they’re good, I’m good to go.” Johnson was one of three female African-American mathematicians known as the “computers in...