The picture of the diminutive Margaret Hamilton, who’s death was announced last week, standing next to the print out of the code that took Apollo 11 to the moon is famous, but perhaps for the wrong reason. It’s famous because the stack of printed books are taller than Margaret and it is the code that gets more attention than she does.

But Margaret wasn’t just a programmer, she had risen to be NASA’s Director of Software Engineering aged just 32 - a role that didn’t exist before she invented the term ‘Software Engineering’ and every line of code was either written by her or approved by her.

But the key to her contribution isn’t clear in that photo. She planned not only for the best, but also for the mistakes. The computing power on ‘Eagle’ the Lunar lander was limited and could only run a handful of programmes simultaneously. Hamilton anticipated that Aldrin and Armstrong might forget to turn some of them off during the landing, so as the alarm sounded that too many systems were running and a potential abort was considered, Hamilton’s software kicked in and shut down systems not essential for landing. She saved the mission from 380,000 km away by anticipating the astronauts mistake.

I didn’t have room to mention that she was a mum at the time of Apollo and would sometimes bring her daughter Lauren to work. During preparation for Apollo 8 her daughter accidentally ‘crashed’ the simulator when she pressed the wrong button when playing ‘astronaut’. Margaret warned her bosses a tired astronaut could do the same, she was ignored and lo and behold, Jim Lovell made exactly that error on Apollo 8 and had to quickly, manually reorientation the spacecraft. Thankfully, she was listened to for Apollo 11.

You could discuss the importance of having a smart woman around to sort out the mistakes of men, or play it with a straighter bat and discuss what being a pioneer in this field must have been like and why programmers still plan for the edge-case mistakes of users - especially when lives are on the line.

-Bill