Who was Katherine Johnson?

A mathematician at NASA whose calculations of orbital trajectories were central to the early American crewed spaceflight programme — and who worked for years in a segregated unit, doing work that was published under other people's names.

The work. She joined the organisation that became NASA in 1953, assigned to a pool of Black women mathematicians working in a segregated section, with separate facilities and separate dining. The job title was "computer" — the work of computation was done by people, and largely by women.

She calculated trajectories for the flight that made Alan Shepard the first American in space, and analysis for John Glenn's orbital flight in 1962.

The Glenn episode is the one that carries the point. By then calculations were being done by electronic computers, which were new and not fully trusted. Glenn reportedly asked specifically for her to verify the machine's output by hand — and would not fly until she had. The request records both the reliability of her work and how much the institution around her had failed to acknowledge it.

She went on to work on Apollo, including the trajectory for the lunar landing and rendezvous, and on the calculations used during Apollo 13 after the accident.

She co-authored a research report in 1960, which was notable because women in her position were routinely uncredited — the convention being that the work appeared under the names of the engineers who requested it.

What her career shows beyond the individual story: that a large amount of technical work in the period was done by people whose names were structurally removed from it; that segregation operated inside an organisation doing frontier science; and that these facts were widely unknown until relatively recently.

Recognition came very late. She received the Presidential Medal of Freedom in 2015, and public awareness followed a book and film in 2016 — more than fifty years after the flights.

She died in 2020, aged 101. Facilities at NASA carry her name.