I would like to point out this article from Nick Heath posted on www.techrepublic.com where you will learn how pioneering IBM software engineers helped NASA launch astronauts into space, and bring them back again--pushing the boundaries of technology as they did it.
With its goal of putting a man on the moon, NASA's Apollo program is perhaps the most ambitious technical endeavor ever undertaken. Throughout the 15 Apollo missions that included six moon landings, the precision needed—in terms of positioning and velocity—to put the craft on the correct trajectory on the journey to and from earth was exacting.
ULD (unit logic device), which is part of the Page Assembly Cards of the LVDC (launch vehicle digital computer) used in the Saturn V Instrument Unit
The computers used during the Apollo missions were impossibly crude by modern standards. Each of the RTCC's five IBM System/360 Model J75 mainframes had about 1MB of main memory, not even enough to load a typical web page in 2017.
"The software that controls what happens when you move your mouse on your PC—the mouse driver for Windows—takes more memory than all the NASA supercomputers put together had for Apollo," said Jones.
NASA was bumping up against the limits of what technology at the time could do, which often meant relying on cutting-edge, and sometimes unproven, hardware and software. And where the tech simply didn't exist, NASA's commercial partners had to invent it.
A period Apollo 16 Luminary 1E Apollo Guidance Computer MIT manual, Section 4 Operational Modes, dated Dec 1971 with about 500-800 pages of software programming and information. Luminary 1E was the name of the software version used for the Lunar Module on the Apollo 15 and 16 missions