Your dishwasher has more brain power than the computer that flew the Apollo astronauts to the Moon.
But don’t let your dishwasher take control of your spaceship anytime soon. That’s not a measure of how basic the Apollo computers were, but rather how much the engineers and programmers in the 1960s were able to do with the modest computing power that was available to them.
The computer they created was a marvel, and its impact is all around us, even though we don’t notice.
NASA knew just how hard it was going to be to navigate through three-dimensional space from the Earth to the Moon: the speeds, the relative motions, the necessary precision, the math, and the speed with which all that math had to be done.
The contract to design the Apollo guidance computer was the first one of the entire project—before the rockets, spaceships, or spacesuits—coming just 10 weeks after President John F. Kennedy’s speech challenging Americans to go to the Moon.
MIT had a division called the Instrumentation Lab, run by a man named Charles Stark Draper who was both a genius and a larger-than-life personality (when he wasn’t designing advanced navigation systems, he was winning ballroom dancing contests). The Instrumentation Lab had 20 years of history designing increasingly sophisticated and precise navigation systems. A staff member had been on the first nuclear submarine to navigate its way under the North Pole, because MIT had designed the submarine’s system to be able to navigate for days while remaining submerged under the waters of the Arctic. If anyone could design the computer and instruments to fly to the Moon, NASA thought, it was MIT.
The challenge was remarkable, starting with the computer at the heart of the system. In the early 1960s, even “small” computers were the size of refrigerators, maybe a couple, lined up next to each other. The Apollo computer would need to be the size of a briefcase.
Computers then required you to submit your programs on stacks of punchcards, then wait hours, or days, for the results. The Apollo computer would need to work instantly—in “real-time” as people started to call it. And the computer would need to have a keyboard and a display, because the astronauts weren’t taking punchcards to the Moon.
At that time, the people using a computer didn’t interact with it. That was the point of the punchcards. Which meant that the people running the computer weren’t really using it. The Apollo computer would need to be designed so the astronauts could run it themselves.