chrislgarry/apollo-11

This repository contains the original source code that ran on the Apollo Guidance Computer (AGC) during the Apollo 11 mission, the first crewed Moon landing in July 1969. Specifically, it holds the code for two separate guidance computers: Comanche 055, which ran in the Command Module that carried astronauts to lunar orbit and back to Earth, and Luminary 099, which ran in the Lunar Module that actually descended to and ascended from the Moon's surface. The code was written at MIT's Instrumentation Laboratory under NASA contract and was digitized from physical hardcopy printouts held at the MIT Museum. The language is assembly, the most basic form of programming, where instructions correspond almost directly to the operations a processor performs. This is not code you would write or run today for practical purposes; it runs on the AGC, a computer from 1969 with roughly 2 MHz of processing power and 4 KB of reusable memory. The repository exists primarily as a historical archive and educational resource. You can browse through the actual logic that guided humans to the Moon: navigation algorithms, guidance equations, trajectory calculations, and the real-time executive that managed tasks with extraordinary precision under severe hardware constraints. The approval records included in the code show signatures from engineers including Margaret Hamilton, who led the software team. You would look at this repository if you are interested in computing history, the origins of software engineering as a discipline, or the remarkable engineering feats of the space age. If you want to actually compile and run the code in a simulator, the Virtual AGC project provides the tools to do so. The code is in the public domain. The primary language is Assembly.