The fact that we are even able to still communicate with it, that it is still sending us data, and that this is even a thing just blows me away. I can’t imagine anything I’ve ever worked on lasting this long. 
this post was submitted on 16 Mar 2024
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What I find insane is that scientists actually do firmware upgrades to rovers like Curiosity. Imagine the stakes of doing firmware upgrades on a device on another planet that you can't communicate with in real time.
I'm amazed that they can do anything like that with a computer built in the early 70s that's been subjected to the conditions of deep space for half a century.
In some ways it kinda helps, the larger physical structures of the older computer hardware make it naturally more resistant to cosmic radiation than new stuff. New stuff just needs more shielding though, so not a huge deal.
But a big part of it staying viable for this long is that it was designed in a way that made it possible. Alot of forethought went into making sure it would last as long as possible. While they didn't expect it to for sure last this long, they did at least want to make sure the reason it didn't wasn't because they didn't plan for the possibility. There was a decent element of luck too, as there were more unknowns back then about what it was going to be subjected to on its journey.
The whole way the onboard computer functions was optimized for remote repair though, because of course the plan was to never see it again, and they knew it was going to need to be repaired alot despite. So at any point in it's "thought process" it is waiting to be interrupted by a call from earth telling it to stop all that and basically dump the entire contents of it's operating memory. And can recieve an entire rewrite of it too, with built-in checks to make sure it recieved it right before starting to operate from it again. Luckily an entire rewrite of everything it can possibly hold is 70kb. So despite the distance and chance of failure, it's still not that bad of an ordeal.
It never occurred to me until now to wonder how Voyager knows it's picking up a signal from NASA. Theoretically, if some bad actors had the means to get it beyond the heliosphere, could a rogue signal be sent to make Voyager brick itself?
I mean I would imagine if someone got their hands on the deep space network in order to have the broadcast power thats a possibility, they would also need to know whatever checksum is sent to Voyager as I would imagine it checks data intergrity before attempting an update
That's why they have a "digital twin" that they can use to simulate their actions. They used to have entire replicas of the probes on the ground they could test against, but a virtual one is much cheaper, and you don't need to physically be there to use it.
I assume they've also engineered them so that if there's a failure in a primary system, it falls back to a more basic recovery system. NASA engineers are pretty thorough in planning for failure scenarios.
Like how they fucked up with the antenna on Voyager 2 last year. They eventually sent a correction signal out, but even if they hadn't been able to, they are set to autonomously reorient the antenna back to Earth every so often, as a failsafe against that very error.
Right? I get stressed out doing that to my router 
Extremely remote debugging
Thank goodness the original engineers turned on kdump
I remember hearing about the things this and Voyager 2 we’re doing as a grew up as a kid in the 80s. I remember hearing Carl Sagan’s Pale Blue Dot while watching the Cosmos series on PBS… and I remember hearing about the end of their missions, as my heart sank.
Then we would hear things once in a while about how they’re still out there, Voyagers 1 and 2, and the what-ifs of trying to get in contact with them. And, now, we are. I love seeing these articles keep popping up and following this ongoing effort to keep trying to get them working again, to see what else we can get these old workhorses to do far beyond their original mission. It reminds me of that childlike wonder for space exploration i once had as a kid, even if we’re just talking about debugging a memory module, lol.
While they did 'complete' their mission in 1989, I don't think we ever completely lost contact with them. They did have to disable the majority of the sensors between then and now, to preserve power, but these all these communications issues were really only fairly recent events.
Excuse me for muddling any of the details and inadvertently invoking Cunningham’s Law. All I meant to say was that it has re-sparked a sense of wonder I haven’t known since the heady days of the 1980s NASA-inspired wonder.
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