Apollo 11 Guidance Computer Source Code: NASA's AGC
/Apollo-11
Apollo 11 Guidance Computer Source Code is publicly readable on GitHub: the actual assembly software that flew on Comanche055 (Command Module) and Luminary099 (Lunar Module) in 1969, transcribed from MIT Museum scans and released as public domain. Read it for the real flight software; skip it if you want a working dev setup, since the repository only points to Virtual AGC for that.
About the Apollo 11 AGC Source Code
Apollo 11 Guidance Computer Source Code is the chrislgarry/Apollo-11 GitHub repository holding the original assembly programs for Apollo 11's two flight computers: Comanche055 for the Command Module and Luminary099 for the Lunar Module. Virtual AGC and the MIT Museum digitized the files from hardcopy scans, and the repo's stated goal is to keep the transcription faithful to those pages, with PRs welcome for mismatches.
Key Contents of the Repository
- ✓Comanche055, the Command Module's AGC program, part of Colossus 2A and listed in the attribution table as revision 055 assembled by NASA in April 1969.
- ✓Luminary099, the Lunar Module's AGC program, part of Luminary 1A and listed as revision 001 assembled by NASA in July 1969.
- ✓A CONTRACT_AND_APPROVALS.agc file that reproduces the original sign-off page, naming Margaret H. Hamilton as Colossus Programming Leader and six approvers from the Apollo Guidance and Navigation Program.
- ✓Code formatted for yaYUL, the assembler named in the repository's own attribution table.
- ✓README translations covering several dozen languages, from Vietnamese and Japanese to Arabic and Russian, kept in the Translations folder.
- ✓A CONTRIBUTING.md file that spells out how to submit fixes against the original Luminary 099 and Comanche055 scans.
How to Explore This Historical Code
- •Read Comanche055 and Luminary099 as digitized historical artifacts rather than as code you'll run.
- •Cross-check a transcribed file against the original scans linked from the README, then open a PR if something doesn't match.
- •Open the CONTRACT_AND_APPROVALS.agc file to see the actual 1969 sign-off page, including Margaret Hamilton's role as Colossus Programming Leader.
- •Read the project in your own language through one of the README translations if English assembly comments slow you down.
- •Move to Virtual AGC, the project the README points readers to, once you actually want to build and run the code.
Strengths
- ✓Digitized from primary sources: Paul Fjeld transcribed the code from MIT Museum hardcopy scans arranged by Deborah Douglas, not from a secondary retype.
- ✓Traceable provenance, down to the CONTRACT_AND_APPROVALS.agc file reproducing the actual 1969 sign-off page with named engineers and dates.
- ✓Public domain, so nothing blocks reading, quoting, or reusing it for research or teaching.
- ✓Actively corrected: the README explicitly invites PRs to fix any drift between this transcription and the original scans.
- ✓Translated into several dozen languages, unusual reach for a repository this technical.
Considerations for Studying the Code
- △There's no build system in this repository. Its Compiling section just points to Virtual AGC instead of giving in-repo steps.
- △The code targets a 1960s computer with no modern equivalent, so reading it takes familiarity with the AGC's own instruction set, not general assembly experience.
- △GitHub shows no standard license identifier for the repository. The attribution table calls the material public domain, but that's not a machine-readable license file.
- △Beyond CONTRIBUTING.md, there's no documented workflow for studying the code, so you're mostly navigating two large assembly codebases on your own.
Related Projects and Resources
Frequently Asked Questions
The repository's attribution table lists the code's copyright as public domain. GitHub itself does not show a separate SPDX license identifier for Apollo 11 Guidance Computer Source Code.
Apollo 11 Guidance Computer Source Code is written in Assembly, formatted for the yaYUL assembler according to the repository's attribution table.
Not directly from this repository. Its README directs anyone who wants to build and run the code to the separate Virtual AGC project instead.
NASA's Instrumentation Laboratory at MIT wrote the software. The repository's own contract records list Margaret H. Hamilton as Colossus Programming Leader.
The README links to translations in several dozen languages, including Vietnamese, Japanese, Arabic, and Russian, kept in the Translations folder.
Apollo 11 Guidance Computer Source Code includes two modules: Comanche055 for the Command Module and Luminary099 for the Lunar Module.
Who should try it — and who should skip
Try this if you're curious about real Apollo-era flight software, teaching a history-of-computing class, or want to see Margaret Hamilton's team's actual code and paperwork. Skip it if you were hoping for a runnable project or modern documentation: there's no build system here, just the source and a pointer to Virtual AGC for anyone who wants to compile it.
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