NASA tries to jog Voyager 1's memory from 15B miles away | Hacker News Reader

NASA tries to jog Voyager 1's memory from 15B miles away

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Voyager 1 is currently 22 hours, 32 minutes and 33.1467 seconds away. I want to celebrate when it is a "Light Day" away.

https://theskylive.com/how-far-is-voyager1

A prior thread calculated it to be November 18, 2026. [see here: https://news.ycombinator.com/item?id=31794292]

The enormity of this statement is really blowing my mind. /If/ we could travel the speed of light, which we can't, it would still take nearly a day to get to Voyager 1, which seems both infinitely far given our current capabilities and remarkably close given how long it's taken to get that far.

No. If you could travel at the speed of light you would take no time to reach Voyager 1.

Actually, you could get anywhere in the reachable Universe.

For example, it takes only 29 years to from Earth to Andromeda galaxy assuming constant 1g acceleration for half of the trip and then constant 1g deceleration for the other half.

Wait why is the 1 LD from earth sooner than 1 LD from the sun? I'd expect it would be the opposite?

Given that the Earth orbits the Sun, I would expect it to swap every half a year. For one half of the year, the Sun should be ever so slightly closer to Voyager 1 than the Earth, and the other half of the year the opposite should be true.

However, considering that the Earth and the Sun are no more than ten light-minutes away from each other, I shouldn't think this would make much difference to our festivities :)

Earth orbits the Sun at an average distance of 149.60 million km [WP]

45 degree angle (see Quora animation): 150000000 * cos(45) = 79000000

Earth projection sits between Voyager and Sun.

"...travelling at around 61,500km/h ": 79000000/61500/24 = 53 days to add the equivalent of that distance in LD time.

Edit: huh, since Earth sits between voyager and the Sun, the LD distance is satisfied for the Sun first.

The light delay to the sun is 8 min which means that the biggest light delay difference to voyager will be about 16min give or take if the sun is directly between earth and voyager. That’s more or less negligible when you are measuring 1 light day worth of delay.

That's the point: it's not negligible when you have to convert it to the distance this craft has to fly.

It's a bit of mental gymnastics, I suggest you do the exercise with paper & pencil to see what happens.

At most it would take Voyager about 190 days to travel 16 light minutes. Considering it’s been flying for 47 years and that it will take 3 more years for it to reach 1 light day of delay half a year more on top of that is pretty negligible in my book.

Yeah, that's why I'm consued why the LD from the sun is later than the LD from the earth.

Because the earth is a bit closer to Voyager than the sun is.

If the earth is closer to voyager than the sun, then the 1 LD from the sun date should be sooner than the 1 LD from the earth date. But in the linked calculations it's later?

It's amazing to think that the farthest away artifact that ever existed is one that people are in constant communication with, and there's only about a month or two round-trip communication time.

Not really even the space part i'm talking about or the unimaginable distance, just how a couple hundred years ago exploration meant you had to send a bunch of guys off in a fleet of boats and you wouldn't know what they found until some of them return a year or two later (if at all).

It's not one month. Voyager 1 is 22h, 33m, 15s away, so it's about a 2 day round trip.

https://voyager.jpl.nasa.gov/

What's even more amazing to me is that:

- we can send a beam of EM radiation, of little power (like a cellular signal),

- to communicate with an object billions of miles away,

- through the vastness of space,

- and the destination object is able to pick up the signal,

- and vice versa.

Well, we need much more on our end than the power of a cellular signal- For instance, one of the support antenna dishes of the Deep Space Network is DSS-42 in Canberra... which is a 70 meter diameter parabolic dish. And the transmit power on our side is in the tens of kilowatts. Literally tens of thousands of times more power needed than a cell phone and directed by a 70 meter dish....

We need that because the dish on the Voyager probes is 'only' 3.7 meters. Still... not a cell phone antenna.

That said, the transmit power of the Voyagers is tiny in comparison to ours and it is closer to that of the cell phone analogy- still more, however, at about 23 watts [1]. So, our end task of receiving that, by the time it gets to us, is damn impressive indeed I think.

[0] https://www.youtube.com/watch?v=FzRP1qdwPKw

[1] https://public.nrao.edu/ask/how-strong-is-the-signal-from-th...

A rule of thumb with transmitter/receivers and gain over astronomical distances, is that the former Arecibo dish could have comfortably communicated with a stock cellular telephone on the moon, but not much further.

Just so I can share this fact with other people too, do you have a source or calculation for this?

sincere question:

How do you think about this evolution of our abilities within the the dark forest theory?

>- we can send a beam of EM radiation, of little power (like a cellular signal), - to communicate with an object billions of miles away,

Meanwhile I can't get 5G reception a few miles from the tower. Another proof 5G is a scam by the illuminati and lizard people.

Working on a remote fix with a day of latency. That's badass, NASA.

And with no way of pushing the power button if things go seriously wrong.

Decent uptime, too.

It's more than one day though, one day is what it takes for the signal to get there, takes twice as much for it to get back. So a ping would take almost two days.

I believe there is a way of pushing the reset button. What you do is feed the bits coming out of the radio receiver into a shift register, and when they match a particular pattern, a reset is triggered.

(It wouldn't surprise me if they could shift between primary and backup computers this way as well.)

One thing that does have great backup time is the RAM, which IIRC is powered by a dedicated power line coming right off the RTGs.

> (It wouldn't surprise me if they could shift between primary and backup computers this way as well.)

The backup is dead.

It is crazy that if we were observing Voyager 1 through a telescope, and we remotely turned on a light on the spaceship, it would still take us 1 day to see the light turn on.

It would be about 2 days from the moment you sent the command to turn it on.

If anyone is in the mood for getting nerd-sniped: I'm curious if it would be possible to see such a light from earth (or earth orbit) using any actually existing telescope, and if so how bright would the light have to be.

I tried with a few LLMs, and they seem to agree (sometimes) around 10^15 lumens. A light wouldn't work, but it seems that a nuclear explosion close to Little Boy's would do it.

PS: The best way to get an answer on the internet is to provide a wrong answer.

I'm reminded of Ron Garrett's writing/talks on remote debugging the Remote Agent for the New Millennium Deep Space 1 (DS1).[0], [1]

[0]: The Remote Agent Experiment: Debugging Code from 60 Million Miles Away - https://www.youtube.com/watch?v=_gZK0tW8EhQ

[1]: NASA Programmer Remembers Debugging Lisp in Deep Space - https://thenewstack.io/nasa-programmer-remembers-debugging-l...

Funny how the current distance from Earth metric on Voyager's site[0] is current going down.

[0]: https://voyager.jpl.nasa.gov/

The speed of Earth relative to the sun is about double the speed of Voyager relative to Earth, so Voyager gets closer in spring.

I'm aware of the why, it's just always cheeky to me to see.

Earth must be moving towards Voyager. Later in the year it will be moving away from Voyager and then the distance will be increasing again. It must be increasing constantly relative to the Sun since Voyager reached solar escape velocity.

> The Voyager team reckons that a single chip responsible for the corrupted portion of memory is at fault...

But sadly, due to a very tight Federal budget, NASA was unable to buy the Extended On-site Service Plan for Voyager 1's memory chips, when their original 5-year Warranty expired in 1982...

I love reading about the Voyagers because it never ceases to amaze me how long they've been working and how far they've made it. Literally the only man-made objects that have the heliosphere...

And to think we did all that to send out a golden record and diagrams of human anatomy that don't include distinctive features of the female body...

Watched the documentary "It's quieter in the twilight" (2022, https://www.imdb.com/title/tt17658964/) the other day, loved the passion the current group working on Voyager have for them.

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