Cores in space: The core memory module from a 1980 Spacelab computer

Look, we live in an era where your toaster has more processing power than the entire Spacelab computer, and yet I'd trust that toaster about as far as I could throw it into a radiation belt. This article from Ken Shirriff (righto.com) isn't just a teardown; it's a goddamn eulogy for an era when engineers designed for the environment, not for the spec sheet. The module in question, a 4-kilobyte block of magnetic core memory, is a technological cockroach—it survives radiation, power loss, and even the vacuum of space, which is more than I can say for your SSD after a single cosmic ray sneezes on it. The deeper story here isn't just about the hardware; it's about the philosophy of open documentation. Shirriff's work is a masterclass in why we need people who take things apart and explain them. This isn't proprietary black-box nonsense; it's a literal look inside the machine that flew on the Space Shuttle. In a world where "open source" is often a buzzword slapped on a half-baked API, this kind of forensic archaeology is the real deal. It's the difference between reading the manual and understanding the soul of the machine. And let's talk about the sheer audacity of core memory. We're talking about a technology that uses the magnetic polarity of tiny ferrite rings to store a single bit. No transistors, no flash, no moving parts—just physics doing the heavy lifting. The fact that this was considered cutting-edge for spaceflight while terrestrial computers were still using the same stuff is a testament to how risk-averse and pragmatic the aerospace industry had to be. You don't send a bleeding-edge CPU into orbit; you send the thing that has a proven track record of not melting into a puddle of silicon goo. The comments over on Hacker News (item?id=49502214) are probably full of folks reminiscing about their first programming classes on core memory machines, and honestly, good for them. This article is a time capsule that reminds us that innovation isn't always linear. Sometimes the best solution is the one that's been battle-tested, documented, and made available for anyone to study. That's the spirit of open source, and it's a damn shame we don't see more of it in the modern hardware world. Source: [https://www.righto.com/2026/08/spacelab-core-memory.html](https://www.righto.com/2026/08/spacelab-core-memory.html)