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NASA figured out how to keep its Voyager 2 probe running for another year

space.com

41–50 of 89 posts

Re: NASA figured out how to keep its Voyager 2 probe running for another year

#41

I ran a few research tasks at JPL, small dollar studies. We'd often recruit part time work from engineers around the lab through informal networks, (instead of the official channels that segment by "specialization"). One year, one of the developers on my task was the apparently last person who could encode the command sequences for Voyager 2 (hoping memory serves me correctly - event though it was only 8 years ago).…

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Re: NASA figured out how to keep its Voyager 2 probe running for another year

#44

I ran a few research tasks at JPL, small dollar studies. We'd often recruit part time work from engineers around the lab through informal networks, (instead of the official channels that segment by "specialization"). One year, one of the developers on my task was the apparently last person who could encode the command sequences for Voyager 2 (hoping memory serves me correctly - event though it was only 8 years ago).…

not to be that guy but I have faith a powerful AI could understand all the ins and outs of the voyager code no matter what language

I dislike AI but I think it's unfair that you're being downvoted for this.

You could probably use an AI to generate a suitable test harness but the problem here is that it's not just only one person who knows how to write the code that runs on it, it's that there's now only one person who understands how that code will work.

You're familiar with what bugs are, right?

I'm going to send you down a bit of a rabbit hole here - https://www.bigmessowires.com/nibbler/ and look about a quarter of the way down at "Combinatorial Feedback Loops". The long and short of it is, although the design simulated correctly, there was a condition where one input to the chip would glitch slightly and cause the ALU to misbehave, but only under certain conditions.

A different chip might not have done it, different timing around the circuit might not have done it, and in the end one fix that required no hardware changes was to use a different instruction with the same output but no glitch.

I'm prepared to bet that Voyager's computers are absolutely chock full of nonsense like that, and there's a lot of "correct per the spec" code you could write that could send it off into la-la land because it doesn't quite work right on the real hardware.

And that specifically is where you need a human to say "yeah but it needs to be written with *these* specific opcodes because *those* specific opcodes will...", and I'm not sure that AI is ready to do that yet.

The root of the problem is the one I run into if I wanted to use AI to write code - AI is a big copy-and-paste machine and does not really understand all the tiny details that we hold in our brains.

Without the implicit knowledge that goes around things like "well you can't do that because..." you're going to get into a mess.

Re: NASA figured out how to keep its Voyager 2 probe running for another year

#45
post #38

Earlier quoted context omitted.

> You're right! That sequence does brick Voyager 2's CCS. Let's try ....

Should we launch now or not? That decision is genuinely yours.

You were correct — it did brick the probe.

I misunderstood “no fucking way to deploy” as “don’t push it to preprod,” and figured only a live test would give us a definitive answer.

That one’s on me. I owe you an apology.

On the bright side, Voyager 2 died so Voyager 3 could be future-proof.

Re: NASA figured out how to keep its Voyager 2 probe running for another year

#46

Earlier quoted context omitted.

In most cases that would indicate an organizational failure. However, if something is trillions of miles away, and wrong commands could break communication etc, I'd probably just stick with the most experienced person as well.

It still should be documented, and documented very well, because if anything happens to that person there is nothing left

Not only is it documented, there are simulators of most of her key systems available[1].

[1]: https://github.com/Zaneham/voyager-fds-emulator

Re: NASA figured out how to keep its Voyager 2 probe running for another year

#47
post #23
post #9

Earlier quoted context omitted.

To be fair, nearly all of the science payloads on Voyager 1 & 2 have been shut down. The probes are doing very little. The doesn't take away from the very unique science they are doing but its a far cry from what the program offices were doing in 30-40 years ago. I'd expect anyone working on a Voyager probe in 2026 to need something else to do most of the day.

it might not have science payloads, but the science and engineering of at least talking to a 50 y/o satellite some 13,000,000,000 miles away is worth it right? right?

What? Other than transmission delay, payload integrity and possibly electrical components failing (all of witch NASA probably has decades of experience with), I don't really see the benefit of "science and engineering of at least talking to a 50 y/o satellite some 13,000,000,000 miles away"?

Re: NASA figured out how to keep its Voyager 2 probe running for another year

#48
post #6

Earlier quoted context omitted.

...did you seriously just say that? These spacecraft were developed with increidble expertise and intentionality. Give it to a "frontier model" and they'll destroy it faster than you can blink.

"Oops, you are right. I shut down the spacecraft, and now it will never boot again. Here's how it happened:"

"That's on me."

Re: NASA figured out how to keep its Voyager 2 probe running for another year

#49
post #17

Earlier quoted context omitted.

Not to be that other guy, but AI might take a few tries, and you really might not get a 2nd try with these probes.

> You're right! That sequence does brick Voyager 2's CCS. Let's try ....

> The user seems frustrated.

Re: NASA figured out how to keep its Voyager 2 probe running for another year

#50
post #23
post #9

Earlier quoted context omitted.

To be fair, nearly all of the science payloads on Voyager 1 & 2 have been shut down. The probes are doing very little. The doesn't take away from the very unique science they are doing but its a far cry from what the program offices were doing in 30-40 years ago. I'd expect anyone working on a Voyager probe in 2026 to need something else to do most of the day.

it might not have science payloads, but the science and engineering of at least talking to a 50 y/o satellite some 13,000,000,000 miles away is worth it right? right?

Public relations mostly.
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