Our story begins with a thirty-second film clip buried within the 2008 miniseries Moon Machines. The footage captures the production activities of a 1965 Raytheon facility. Here, a dozen women sit at low desks across from one another, working underneath the bright light of industrial task lamps. A young woman facing the camera wears a white lab coat with rolled up sleeves and picks up a long needle in front of her. She passes the needle through a grid of metal eyelet holes and a woman sitting on the other side passes it back and repeats the process again.

To any observer, this work could look like weaving. Threading an implement back and forth through a loom-like instrument to produce a woven structure much like a textile. But in this case the process involved unusual materials: ferrite core beads, copper wire, and electrical current. With these ingredients, the women contributed a key innovation to the Apollo moon missions. They wove the computer memory that first sent people to the moon.

This weaving process — what NASA engineers nicknamed “LOL method” for the “Little Old Ladies” who operated the machinery — produced a form of non-volatile digital information storage called core memory. 

The software programs for the Apollo Guidance Computer were permanently stored within a type of core memory called “core rope memory.” In every core rope, there were wires of two types: address wires and sense wires. The sense wire was especially important. It was woven through the cores in a pattern, physically encoding the 1s and 0s of binary code. When the wire passed through the core it would be read as 1. When it passed around the core (missing it completely) it would be read as a 0. The weavers had the help of a machine that would let them know which cores needed threading.