First computer on the moon

Computers & Mobile Science
First computer on the moon


Here’s a really fascinating piece on the BBC about NASA programmer Don Eyles and the team behind the storied AGC (Apollo Guidance Computer). Don was only 23 when he got the gig. Maybe it was good that he was young and naive. As he says: “I don’t recall the risk and the responsibility and the fact that other people’s lives were to some extent in our hands.”

There are few instances in which I’m happy to be as old as I am. The fact that I got to live through and be an active observer (aka space geek!) during the Apollo program is one of those times. I still get chills reliving some of that footage.

There’s a great jargon term in here, too: “LOL memory.” It stands for “Little Old Lady memory” and refers to the “rope core memory” used in the AGC that required teams of (women) employees to weave meters and meters of copper wire around magnetic cores.

Weaving the way to the Moon [Thanks, Brian Jepson and Mike Loukides!]

14 thoughts on “First computer on the moon

  1. svofski says:

    I’m not a native speaker and it bugs me every time when I see this. Isn’t the AGC famous, as in being valuable, of great service and memorable and not “infamous” or “notorious”, as in buggy and killing people?

  2. AndyL says:

    Perhaps “infamous” refers to the way it failed during landing and required Armstrong to take over manual control.

    Or am I thinking about a different computer?

    1. Brian McNett says:

      The AGC performed flawlessly. The 1201 and 1202 alarms were due to the fact that Armstrong and Aldrin had unnecessarily left the rendezvous radar on, overloading the computer’s input buffer. The landing was supposed to be done with the radar off (it was useless in a landing situation anyway).

      Of course the reason for leaving the radar on, was that there was no assurance that they wouldn’t have to quickly abort and return to orbit.

      Complexities like this are often overlooked. Later missions left the radar off. NASA continued to use the AGC without modification for the rest of the program.

    2. svofski says:

      Thanks. The failure wasn’t mentioned in this video and article text and I didn’t know about it at all, so this wasn’t obvious to me. It must be some universal knowledge then?

  3. Gareth Branwyn says:

    You’re right. There has been a meaning drift on that word, and while I agree with the idea that, in language, people ultimately vote with their usage, “infamous” is not what I meant here, even in its weaker form. I was referring to the many stories of the absurd lengths that were gone to in creating the AGC (like the hand-woven “rope core memory”), the nervousness around this system, using new technologies like ICs, and of course, the minuscule processing power and memory involved. Maybe “storied” is the right adjective.

  4. Anonymous says:


  5. Ben says:

    Why bother ?
    They did not step on the moon

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Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. And he has a new best-of writing collection and “lazy man’s memoir,” called Borg Like Me.

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