V'ger has evolved
this post was submitted on 15 Jun 2024
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Just curious: is the data of value for research or is it more like "look at us, we can repair from a distance"?
It's the only instrumentation we have at that distance that can measure things like solar irradiance.
Interesting question though, which sent me down a rabbit hole to see the capabilities of the instrumentation.
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There are currently five science investigation teams participating in the VIM. The science teams for these investigations are currently collecting and evaluating data on the strength and orientation of the Sun's magnetic field; the composition, direction and energy spectra of the solar wind particles and interstellar cosmic rays; the strength of radio emissions that are thought to be originating at the heliopause, beyond which is interstellar space; and the distribution of hydrogen within the outer heliosphere.
There are 4 operating instruments on-board the Voyager 1 spacecraft. These instruments directly support the five science investigations teams. The Planetary Radio Astronomy Investigation (PRA) is no longer working on the Voyager 1 spacecraft and the Ultraviolet Spectrometer Subsystem (UVS) is no longer working on Voyager 1 or Voyager 2.
Considering that's one of the two objects humanity ever have on direct contact with the medium outside the limits of our solar system, and the only tool we'll have there for at least four decades, I'd argue that yes, it is pretty valuable.
The repair from distance part is nothing to be shy about, too.
Yes the data is valuable for research. You and I may not understand any of it, but its useful to someone. As for repairing from a distance, that thing has been traveling for 46 years and gone far. For reference, it passed Neptune back in 1989.
It would take many years for a new probe to reach those distances, so if it can be repaired, it shall.
https://en.m.wikipedia.org/wiki/Voyager_2
Hypothetically, lets say it only takes 30 years for a new probe with updated tech to reach where Voyager 2 is now. If V2 died today, thats half of someone's career spent waiting for the new probe to arrive. Multiply that by everyone using the probe for research and you have a ton of wasted potential.
I'm aware that sending something to do the repairs isn't an option, my question was whether it's worth it (and apparently it is) or if it's more an experiment about long distance repairs which by itself is very expressive already.
I'm not sure why I'm downvoted. Maybe I worded my question badly or it's because it was a question I could have googled on my own. I don't know and neither do I care. I don't think you downvoted me, if it sounded that way. Just now saw it and wondered why
So some years ago, the probe went into some area between our solar system and interstellar space. Getting info back about that is quite useful in learning more about that area.
I'm not sure if its through it yet, but if it is, then we're getting data back about what's after that as well. Does that data change over time? What if there's yet another transition area and we learn about it?
Having something actually there helps us know if all these theories are right, and the more data we get, the more sure we can be
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It's like the Jason Vorhees of spacecraft
That's just Jason X.
I'd pay to see Voyager beat a teenager to death with another one in a sleeping bag. Sounds compelling.
That's far out!
It is just incredible to me that we have the ability and knowhow to send instructions to a 40 year old transistor computer to reprogram itself and get it working again with just radio signals.
Same. That was incredible.
...from 15.2 BILLION miles away.
And it can reply by basically shining a (very high-frequency) flashlight back at us.
What they did was close to wizardry.
With no way to fix the chip, the team instead split the code up so it could be stored elsewhere. Initially they focused on reacquiring the engineering data, sending an update to Voyager 1 on 18 April 2024.
It takes 22.5 hours for a radio signal to travel the 24 billion kilometres (15 billion miles) out to Voyager 1, and the same back, meaning the spacecraft’s operations team didn’t receive a message back until 20 April.
But when it arrived, they had usable data from Voyager 1 for the first time in five months.
https://www.skyatnightmagazine.com/space-missions/how-fixed-voyager-1
Here's a fun fact that I think of every time I read about light delay.
We assume the speed of light is the same in all directions but there's no way to prove that it is.
It could be light speed is instantaneous in one direction, and half the speed we think it is in the reverse. Any test we could devise depends on information traveling in two directions, nullifying any discrepancies in light speed.
The speed of light in a vacuum unaffected by external forces such as gravity should be the same no matter what direction it is in. I'm not sure why it wouldn't be. That's like saying a kilometer is longer if you go East than if you go West.
However, it's actually far more complicated than that, and much of it beyond my understanding.
https://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html
That said, direction should not matter.
There's no reason it wouldn't be. The point is that it's impossible to prove that it is. There is no conceivable experiment that can be performed to prove the two-way speed of light is symmetric.
That's not how anything works. It's impossible to prove that the universe wasn't created last Thursday with everything in place as it is now. There's no point in assuming anything that can't be proven has validity.
...but that's exactly what you're doing. The fact that light travels at the same speed in all directions cannot be proven. You're the one insisting that it does.
I'm not insisting anything. I'm saying that, based on everything we know, the direction of light has no bearing on its speed.
Suggesting that it does just because we don't have evidence that it doesn't is no different, as I said, as claiming the universe was created last Thursday.
Maybe the speed of light doubles when it goes through the exact right type of orange. You can't prove it doesn't.
This is slighlty different though, we only know the two-way speed of light, not the one way speed of light.
We only know that this trip, to and back, takes x seconds. We cannot prove that the trip to the mirror takes the same length of time as the way back.
The special theory of relativity for example does not depend on the one way speed of light to be the same as the two way speed of light.
Why would the one-way speed be different? For what reason? Just because you think it's possible?
For no reason. No one is saying that it is different, only that it's impossible to prove one way or the other. Light traveling the same speed in all directions, and light traveling at 2x c away from an observer and instantaneously on the return, and every other alternative that averages out to c for the round trip, are indistinguishable to any experiment we can conduct.
And it's impossible to prove that just the exact right type of orange will double the speed of light.
But there's no reason to speculate either thing without a reason for the speculation. Your reason seems to be "I think it would be cool."
I don't think you realize it, but this is a very similar argument to "you can't prove God doesn't exist."
Take 30 seconds to at least glance at the article the other user posted. It's not just myself, there are plenty of very interested physicists who also find the unprovability of the one-way speed of light interesting.
I'm also not sure what your point about orange is supposed to be. Are you suggesting that there is a particular spectra of light that we cannot test?
My reason for being interested isn't just that I think it's "cool". I think it's fascinating that a fundamental underpinning of physics has such a gap in its experimental verifiability.
No, I'm saying it's just another version of Russel's Teapot.
It kind of is. It's just the thing being asserted without proof is the one-way speed of light. That you don't seem to find that interesting I guess is where we differ.
Synchronise two high-precision clocks at different locations. Transmit the signal from A to a receiver at B and then send a signal back (or reflect the initial signal) from B to A. Both locations will record the synchronised time that their sensors picked up the transmission. Then, compare their clocks.
How would you sync them... ? Seems to beg the premise.
Sync them right next to each other, then move one of them. The other way you could test this theory is to have one clock tell the other the time over an optical link and then have the other do the same. If the speed of light was different in different directions. Each would measure a different lag.
Well, moving them is out of the question, since, you know, motion will change the clocks time. If you re-sync them, you bake the "error" into your framework. If you try a timer, the timer is offset. If you try and propagate a signal, the signal is offset. And eventually, you have to compare the two times, which muddies the waters by introducing a third clock.
Basically, there is no way to sync two clocks without checking both clocks, ergo, no way of proving or disproving. That's the premise.
In practicality, I assume it is constant, but it's like N=NP. You can't prove it within the framework, even if you really, really want to believe one thing.
If you move one clock very slowly away from the other, the error is minimised, perhaps even to a degree that allows for statistically significant measurements.
To cite the Wikipedia entry that one of the other commenters linked:
"The clocks can remain synchronized to an arbitrary accuracy by moving them sufficiently slowly. If it is taken that, if moved slowly, the clocks remain synchronized at all times, even when separated, this method can be used to synchronize two spatially separated clocks."
Except if you continue reading beyond your Quote, it goes on to explain why that actually doesn't help.
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With a detector and very accurate clocks, it would be easy to say "I'm going to send a pulse at 2pm, record when you receive it" that's measuring it in one direction
The very accurate clock needed in this case is physically impossible as far as we know, there's no way to measure it as far as our current understanding of physics goes.
Though if you can figure out a way you should publish a paper about it.
Can you cite some literature to back up that claim? Stating that something like acceptable clock synchronisation (a well established and appreciated method in the measurements of physical effects) is impossible in and of itself is something so bold that no one can just take your word for it.
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It's just a thought exercise. There are several reputable YouTube videos on this topic. None of them claim that the speed of light isn't the speed of light. They're just demonstrating that we can't prove it with current technology. Similar to the difficulty it took to finally prove that one plus one equals two. We know that's correct, but it took years to prove it.
Another interesting way to conceptualize it is that the speed of light is infinite and it's causality/information that is limited to c. You shine a light at the moon and it takes 1.3 seconds for the "fact" that the light was turned on to propagate that far.
Cixin Liu imagines exactly that towards the end of the Three Body series. Among other things, which make the series worth absolutely slogging through at points.
Couldn't we send out two devices in different directions, wait a decade, have them shine light at eachother simultaneously, record when they receive the light, then send the times back to earth?
Your question is a good one. It indicates that you don't have an understanding of time dilation and frame of reference. An explanation of the theory of relativity is pages long.
The first book I ever read on the subject, and IMO the best introductory text for any non-physiscist, is Stephen Hawking's "A Brief History of Time". But, any introduction to relativity should answer your question.
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Incredible is the right word, how does this still work after more than 47 years? How do they even still have energy to send and receive signals? That's one heck of a durable power source. How do the computers and sensors still work? The reliability and durability of these probes is amazing. NASA truly had some reality wizards doing what seems like magic to accomplish this.
Either that or, aliens have been helping out and repaired it from time to time.
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It's literally the most far out object there is
o7
this detecation is impressive.
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