The Mars Society’s San Diego chapter gives a surprising answer to the question “Does the Space Shuttle’s Computer Really Run on Just One Megabyte of RAM? “
It’s true: The brain of NASA’s primary vehicle has the computational power of an IBM 5150, that ’80s icon that goes for $20 at yard sales.
… Besides, a complete overhaul would be horrendously expensive. The GPC’s oftware would have to be completely reconfigured for a modern computer and tested until proven flawless.
For proof that you shouldn’t fix a space computer if it ain’t broke, consider Russia’s Soyuz space capsule, which since 1974 has been running Argon-16 flight-computer software with just six kilobytes of RAM. In 2003 the Russians rewrote some of the spacecraft’s software, which experts suspect led to its subsequent crash-landing in a desert in Kazakhstan.
[Via Chronicles of the Dawn Patrol]