Many of you have probably heard the repeated story of the first Moon landing in 1969 almost getting undone by a bunch of onboard computer glitches:

There could not be a worse time in the flight to have computer problems. At, the time the press gleefully reported how Armstrong seized manual control from a crippled and failing onboard computer and managed to heroically and single-handedly land the spaceship on the surface of the Moon against all odds.

Robert Wills argues against this narrative in this 2020 talk, wanting to shine a spotlight away from Neil Armstrong and toward people who designed the software (among them Margaret Hamilton), and the mission control’s Steve Bales, who made a decision not to abort the launch as the 1201 and 1202 errors were piling up.

The argument: the computer was working as intended, it fixed itself over and over again owing to its clever software, and it actually helped Buzz Aldrin understand (at least subconsciously) what led to the seemingly random and distracting computer errors.

The above is more of a traditional talk than the videos I usually share – a bit more technical, taking up an entire hour, and with generic slides – but it’s buoyed by Wills’s enthusiasm and knowledge.

Besides, it’s lunar landing! Did you know about DSKY and its fascinating keyboard and UI? Did you know the spacecraft’s window was part of the interface, too? Or that its software was woven into the hardware? Or that the Apollo 11 had a… guillotine in it?

Unaddressed in the talk, but also important:

An unsung hero of the decision not to abort the landing is Richard Koos, a NASA simulation supervisor who […] 11 days before the launch of Apollo 11, put the team of controllers including Bales […] through a simulation that intentionally triggered a 1201 alarm. […] Unable to figure out what the 1201 was, Bales aborted that simulated landing. He and Flight Director Gene Kranz were dressed down for it by Koos, who put the team through four more hours of training the next day specifically on program alarms. When the 1202 and 1201 alarms occurred during the actual landing, Garman, Bales, and even Duke recognized them immediately.

Fortune favors the prepared.