Original Apollo 11 Guidance Computer Source Code Now on GitHub

Original Apollo 11 Guidance Computer source code for command and lunar modules

Original Apollo 11 Guidance Computer Source Code Now on GitHub

I have made the original Apollo 11 Guidance Computer source code for both the Command and Lunar Modules publicly available on GitHub. Digitized from historical scans, this repository preserves the exact software that guided the first moon landing. I welcome contributions to correct any transcription errors found when comparing the code against the original NASA documents.

The goal is to be a repo for the original Apollo 11 source code.
  1. wim

    This is such an interesting peek into the engineering of these sort of systems with very constrained resources at the time. Like any random file you open contains little pragmatic design decisions like this

    https://github.com/chrislgarry/Apollo-11/blob/master/Comanch...

    # THE POSITION OF THE MOON IS STORED IN THE COMPUTER IN THE FORM OF

    # A NINTH DEGREE POLYNOMIAL APPROXIMATION WHICH IS VALID OVER A 15

    # DAY INTERVAL BEGINNING SHORTLY BEFORE LAUNCH. THEREFORE THE TIME

    # INPUT BY THE USER SHOULD FALL WITHIN THIS 15 DAY INTERVAL.

    Better be back home in 15 days! ;)

  2. buredoranna

    https://github.com/chrislgarry/Apollo-11/blob/master/Comanch...

    I feel like "BEWARE"... is, given the context, what we would now likely call "load-bearing"

    COMPTGO EXTEND # USED TO COMPUTE TTOGO

    QXCH PHSPRDT6 # ** GROUP 6 TEMPORARY USED .. BEWARE **

    (edit: formatting)

  3. starkparker

    Happy 10-year anniversary to this repo being shared on HN.

    Most significant discussion: https://news.ycombinator.com/item?id=12048945, 652 points, 145 comments on July 7, 2016

    All previous submissions: https://news.ycombinator.com/from?site=github.com/chrislgarr...

  4. BinaryRage

    For an terrific AGC deep dive, I can’t recommend Marc’s restoration videos enough. The work they did was incredible:

    https://youtube.com/playlist?list=PL-_93BVApb59FWrLZfdlisi_x...

  5. mellosouls

    More here (linked in the repo):

    Original scans (featuring Margaret Hamilton!)

    https://28gpc.csb.app/

    The Virtual AGC Project

    Spaceborne Computer Systems

    https://www.ibiblio.org/apollo/

    The purpose of this project is to provide the original flight software and emulations of the onboard guidance computers flown in historical spacecraft, so that the flight software can be run on computers commonly available to the public today. The particular emphasis is on the Apollo Guidance Computer (AGC) flown in lunar missions in the 1960's and 1970's.

    Wikipedia on the hardware:

    https://en.wikipedia.org/wiki/Apollo_Guidance_Computer

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