It seems a bit odd, then, that it uses such an old technology; according to Dashevsky and Balzano, the language the scripts are written in is called Nombas ScriptEase 5.00e. According to Nombas’ (now-defunct) website, the latest update to ScriptEase 5.00e was released in January 2003 — yes, almost two decades ago. There are people who can vote who weren’t born when the software controlling some of the JWST’s most vital instruments came out.
This knowledge has been bubbling up on the internet in Hacker News and Twitter threads for years, but it still surprised quite a few of us here at The Verge once it actually clicked. At first blush, it just seems odd that such a vital (not to mention expensive) piece of scientific equipment would be controlled by a very old version of a technology that’s not particularly known for being robust.
After thinking about it for a second, though, the software’s age makes a bit more sense — while the JWST was launched in late 2021, the project has been in the works since 1989. When construction on the telescope started in 2004, ScriptEase 5 would’ve only been around two years old, having launched in 2002. That’s actually not particularly old, given that spacecraft are often powered by tried-and-true technology instead of the latest and greatest. Because of how long projects like the JWST take to (literally) get off the ground, things that had to be locked in early on can seem out of date by more conventional standards when launch day rolls around.
This knowledge base, by the way, also contains a few more details on the telescope’s 68 GB SSD, saying that it can hold somewhere between 58.8 and 65 gigabytes of actual scientific data. Wait, did I forget to mention that? Yes, this telescope’s solid state drive has around the same capacity as the one that was available in the original 2008 MacBook Air.
Well, NASA’s document says that this way of doing things gives “operations personnel greater visibility, control and flexibility over the telescope operations,” letting them easily change the scripts “as they learn the ramifications and subtleties of operating the instruments.” Basically, NASA’s working with a bunch of files that are written in a somewhat human-readable format — if they need to make changes, they can just open up a text editor, do a bunch of testing on the ground, then send the updated file to the JWST. It’s certainly easier (and therefore likely less error-prone) than if every program was written in arcane code that you’d have to recompile if you wanted to make changes.