“On the Moon is a photo of my family. I pray it reminds you that we and America and all of the world are cheering you on.” Apollo 16 astronaut Charlie Duke recorded a message for the Artemis II crew. Fitting that they hear his words as they close in on their lunar destination.

Before silicon chips existed, NASA relied on handwoven memory to run the Apollo Program. Before silicon chips, NASA powered the Apollo missions with magnetic core memory. These computers used hand-woven grids of tiny magnetic rings, each storing a single bit by flipping its magnetic direction and retaining data without power. That durability made core memory ideal for spaceflight and even gave rise to the term “core dump,” which once meant reading data directly from the physical cores. Modern computing may be microscopic, but its roots were tangible, manual, and grounded in pure physics.