[subract]

For those interested in learning more about the challenges in keeping the probes alive, the 2022 documentary It's Quieter in the Twilight follows the small, incredibly dedicated team working the project. Free to stream on Prime.

The simple fact that many of the original engineers are no longer alive presents significant challenges in and of itself.

[ojosilva]

I came to say the same, and post this link to the trailer:

https://www.youtube.com/watch?v=8vJT8AW0wYw

[noelwelsh]

Those ancient Sun machines take me back a bit!

[dylan604]

Thanks for the reco. I would have never found this browsing Prime hidden in all of their FreeVee push.

[chgs]

I stopped my prime subscription after years (decade+?) because they decided to double dip and put in adverts. Such a shame. They’ve lost £360 so far from me based on my normal Amazon spending for their decision.

[Solvency]

I fundamentally don't understand why this project is seemingly so poorly documented? I've read articles describing the current teams having to still reverse engineer things by scrutinizing random documents and sketches as if it's still this very unknown system.

[xenadu02]

The project was not really designed to reach interstellar space originally. It was a somewhat rushed program to take advantage of the "Grand Tour" where the gas giants would all be aligned enough that a gravity-assist orbit could allow a spacecraft to fly by each of them. The alignment in question only happens every 175 years.

The interstellar portion was an add-on after the success of the original mission. The spacecraft were still operating so why not just keep operating them?

No one designing or building the probes imagined they'd still be operating 50+ years later. Even if they did space programs are constantly under threat from budget cuts so you can't exactly waste money on what-ifs for the future: you must focus on making the official mission succeed.

Also remember that the "desktop PC" was not yet a thing when this was designed. Engineers were drawing everything on paper. Storage space was extremely expensive in any case.

A modern program would (and most do!) put various versions of drawings in a version control system. Source would use an SCM so code history would be available. Even things like meeting notes would be available and searchable digitally.

[KineticLensman]

I remember reading about the inquiry into the UK RAF Nimrod aircraft that came down in Afghanistan in 2006 killing its crew of 14 [0]. A significant finding was that recovering the design history and maintenance records involved trawling a massive number of filing cabinets / cardboard boxes scattered in sites across the UK, and was a significant cause of the missed opportunities to uncover the design flaws and near misses that preceded the crash. (long story short: internal fuel leak near a very hot exhaust pipe)

[0] https://en.wikipedia.org/wiki/2006_Royal_Air_Force_Nimrod_cr...

[TheCondor]

When was the first source code control system released? SCCS was like 1973 and the Voyager code was probably pretty much buttoned by then; with whatever practices that they thought was stable state of the art practices at the time. I imaging that this was a collection of "golden tapes" or something. Now the concept of revision control seems pretty self validating but you're talking about undergoing a culture change on your software team, pretty close to launch.

Then the voyager hardware was bespoke.

We just live in a different world now, they didn't know how to do software engineering like we do. They were just figuring it out. I really don't know the history of it but Voyager systems may have been produced on punchcard. Like the original source code might be physical for parts of the system.

[toast0]

If they have random documents to scrutinize, doesn't that mean that it's documented?

When I work on undocumented systems, it's because someone wrote code with no design docs, no (retained) notes, no requirements, no specs, and it's been determined that it doesn't work right. All I have is the code, and current observations.

[Johnny555]

I'd imagine that a lot of the undocumented stuff was for things that were obvious to an engineer at the time -- I doubt many engineers working on it at the time thought that the probe would outlive their own lifetime.

I've run into lots of software comments in legacy code that refer to features or systems the company used to have that were deprecated years ago and are nearly meaningless today. Knowing that a flag was set to match the flags from the WOPR sytem isn't that useful when WOPR hasn't existed since before I joined the company.

[anigbrowl]

At the time engineers imagined it having a relatively short operating life, and (imho) also thought we would be putting out a lot more probes. During the Cold War space exploration provided both prestige and a technological proving ground. After the USSR fell, a lot of Congressional enthusiasm for space projects diminished and management became increasingly risk-averse because budgets were much tighter.

[mardifoufs]

I think it's because it was more of an awesome moonshot project that didn't really fit into NASA's shifting goals at the time and with the shuttle overshadowing everything else that happened then. No one was really expecting this much from the probes

[nonethewiser]

I imagine its a problem of distance, feedback, and lack of any analogous test environment.

[andyjohnson0]

Looks fascinating, but the only place I can find to watch it here in the uk is Prime Video. Does anyone know of legal options for those who don't want to give Amazon their money - still less sign up for a Prime subscription?

[greazy]

Try one of the options listed here

https://www.itsquieterfilm.com/where-to-watch

Most of the options don't offer the movie in my region :(

[mintycrisp]

Here is the official list of options to see if any alternatives work for your location -> https://itsquieterfilm.com/where-to-watch

[mbirth]

Eh, even Prime Video shows “This video is currently unavailable to watch in your location.”

[orev]

If you have Prime, it’s free to stream, while other things on Prime might need you to pay to rent/purchase to watch it.

[abfan1127]

Some things are not free, even if you "have prime"... so if you have it already, then the cost is already paid... but that's a lot of words. perhaps "included with price of admission"

[Kwpolska]

Prime Video is both a subscription service and a one-off rental* service. Prime subscribers get free access to some movies offered for rental.

* Either short-term rental, or long-term rental described as a purchase.

[AlecSchueler]

And don't forget the cost of your internet subscription, streaming drive and electricity usage.

[enlightens]

Prime also has some shows you have to pay individually for above and beyond the subscription cost. This particular one is no extra cost, "free", once you have a subscription.