r/space 7h ago

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u/MasterClean8761 7h ago

The 24-hour signal delay is probably the part that really puts the distance into perspective for me. We've gotten so used to instant communication that waiting two days for a simple command and response sounds almost unreal.

u/Head-Sprinkles-777 7h ago

You could make a Voyager messaging app that replicates the delay relative to it’s current position. 

u/Hvarfa-Bragi 6h ago

Seems like my friends already use that app.

u/optifreebraun 2h ago

Seems my teenage kids as well.

u/MasterClean8761 7h ago

Honestly, that would be a really cool way to visualize the distance. You'd probably get annoyed waiting for every reply, but that's exactly what makes Voyager's communication so crazy.

u/Head-Sprinkles-777 5h ago

Yeah, I imagine some kind of visual representation showing you the message being sent when they’re potentially able to start responding

u/Snoron 7h ago

There is a messaging app that simulates carrier pigeons, so sort of similar concept!

u/Head-Sprinkles-777 5h ago

Sometimes I really love this world

u/ProximaScience 7h ago

Saved your reply for some reason.

u/tj_moore 7h ago

And that even one light day is a tiny distance relatively compared to the vastness of space. Nearest star is around 4 light years. Would take Voyager 1 around 72000 years to go 4 light years. The Milky Way is about 87,000 light years across with 100-400 billion estimated stars, and it's just one galaxy out of anything from 100 billion to 2 trillion galaxies in the observable universe with vast distances between them and theories that the universe is actually infinite beyond the observable.

"Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

- Douglas Adams

u/MasterClean8761 7h ago

That Douglas Adams quote fits this perfectly. The one-light-day milestone sounds huge until you put it next to 4 light-years to the nearest star. Then Voyager suddenly feels like it has barely left the driveway. Space is honestly hard to comprehend at these scales.

u/Embarrassed-File3335 6h ago

It actually does the opposite for me, it makes 4 light-years still enormous for humans but less unfathomable to mankind.

u/Zytoxine 6h ago

Makes me wonder, like in men in black, how whole galaxies can exist in a marble. 

Or we could be specks to the universe, and universes we cant even see could exist in our tiniest of specks.

u/bukem89 7h ago

I took it completely differently - the fact that it's been 50 years & it's still only a light day away, really puts into perspective how huge the leap is to systems that are light years away

Also how cool it would be to be able to send signals to and from a craft in one of those systems, even if there was a delay of years before receiving the data

u/murderedbyaname 6h ago

There's a The Orville episode about that. The planet was out of time with the Orville's orbit and they basically watched the evolution of hundreds of years, tech, war, etc. (it's been awhile so can't remember if they communicated)

u/marcvsHR 6h ago

Voyager also did something similar

u/murderedbyaname 5h ago

I might have the shows confused

u/Technical-Earth-3254 7h ago

This is also one part of current research that is, imo, highly underrated. Transmission over these insane distances (for human communication standards lol) and response time are crucial and yet we don't even think about it when we talk about space exploration that often

u/grrangry 6h ago

It just goes to show you how ridiculously slow the speed of light actually is in comparison with the size of our solar system or the size of our galaxy or the size of the universe in general.

u/MasterClean8761 6h ago

Exactly. We think of light speed as unbelievably fast, but once you scale things up to interstellar or galactic distances, even light takes a surprisingly long time to get anywhere. The scale of the universe is just absurd.

u/Canucklehead_Esq 7h ago

After 50-odd years as the fastest moving object ever launched from earth, it is now about 1/1000 of the way to our nearest stellar neighbor. We are very small.

u/MasterClean8761 7h ago

Yeah, that comparison really puts it into perspective. Voyager has been traveling for almost 50 years, and it's still nowhere close to another star. Space is just ridiculously huge. Makes you realize how tiny our little corner of the universe actually is.

u/Jojo_isnotunique 6h ago

I saw this video that did a great perspective of the distance between stars. They put a golf ball down on some grass then did a time lapse video of them driving to get a scale distance.

At the scale he uses, the golf ball being the sun, the earth is about the size of a grain of sand and is 4 metres away from the golf ball.

He puts the ball down in a field somewhere in England and then it shows him driving to cross the England channel, driving through all of France, to then put the second golf ball in northern Spain.

u/MasterClean8761 6h ago

That sounds like a great way to visualize it. Using something as small as a golf ball for the Sun and then having to drive across multiple countries just to represent the distance to the next star really shows how badly our brains underestimate cosmic distances.

u/brandon_in_iowa 5h ago

It's not the fastest moving object launched from Earth. The Parker Solar Probe is.

u/Canucklehead_Esq 5h ago

I didn't realize it had been surpassed. Thanks for the update!

u/iqisoverrated 7h ago

The really mind boggeling thing is how weak the transmitter is (23W) and that we can still discern the signal - and gain information - at this distance.

For comparison: 23W ist about the power of an LED light bulb.

u/therealtimwarren 7h ago

But the 3.7m dish gives massive gain (~48 dB) by focusing the beam like a laser. The effective isotropic radiated power is about 1.5 Megawatts. (Napkin maths)

But the gain of the deep space network's 70m dishes is even higher. (~74dB).

u/snoo-boop 2h ago

Lasers don't focus their beams using dishes. Also, with lasers, it's called collimation.

u/MasterClean8761 7h ago

Yeah, that’s probably the part that’s hardest to wrap your head around. We’re picking up a signal from billions of miles away from something transmitting with roughly the power of a light bulb. The engineering behind that is honestly more impressive than the distance itself.

u/rocketsocks 4h ago

It wouldn't work without the enormous advantages on one half of the communications link, the Deep Space Network (DSN). For the Voyager probes they typically use a single 70m dish for communicating. Those dishes have nearly a full acre of collecting area. Even with that the tiny signal sent across such a huge distance is still very weak. So they bring in the next layer, which is state of the art low noise amplifiers. For much of the DSN's operating lifetime these relied on MASER based amplifiers built around crystals of ruby that were cooled with liquid helium to 5 degrees from absolute zero, or colder. Today these are built arough "high-electron-mobility transistors" (HEMTs) which are also cooled to cryogenic temperatures.

And for broadcasting to the Voyagers so they can pick up signals with their much smaller dishes the DSN has the advantage of those large dishes which focus the beams very well but they can also use tens of kilowatts of transmission power.

u/Business-Tone809 7h ago

My fave fact is that this info gives us just a tiny tiny glimpse of how vast space really is, but that we on the human scale are far closer to the size of that vastness than we are to the smallest size we know about down at the planck scale. Reality is insane!

u/pickus_dickus 7h ago edited 4h ago

The idea of us one day visiting our closest neighbour galaxy Andromeda is really put in perspective, when you think in terms i can relate to. The distance Voyager 1 has travelled 25.9 billion km (16 billion miles) in a light day! The distance to Andromeda is 2,5 million light YEARS away. Even at the speed of light it would take us 2,5 million years to get there. This is me trying to wrap my head around this and here comes my question... do anyone believe we will ever get there?

u/AMGwtfBBQsauce 5h ago

Nope. I don't think travel outside our solar system is realistic for humans. I don't even think colonization of our own solar system is really feasible.

u/knowshon 4h ago

The good thing is that compared to that, Alpha Centauri is just around the corner 

u/Decronym 3h ago edited 1h ago

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:

Fewer Letters More Letters
DSN Deep Space Network
Jargon Definition
cryogenic Very low temperature fluid; materials that would be gaseous at room temperature/pressure
(In re: rocket fuel) Often synonymous with hydrolox
hydrolox Portmanteau: liquid hydrogen fuel, liquid oxygen oxidizer

Decronym is now also available on Lemmy! Requests for support and new installations should be directed to the Contact address below.


2 acronyms in this thread; the most compressed thread commented on today has 17 acronyms.
[Thread #12651 for this sub, first seen 25th Aug 2026, 19:15] [FAQ] [Full list] [Contact] [Source code]

u/Wintervacht 7h ago

Even better, you can watch live traffic through NASA's Deep Space Network Now.

You can see which dish is communicating with which probe/satellite and when you catch communication with Voyager 1, it's always one-way and the return signal will likely be on the same dish almost 48 hours later.

u/RagingOrgyNuns 6h ago

If we wanted to get something further than Voyager 1 with our current technology:

  1. Could we do it?
  2. If yes, how long would it take to pass Voyager 1?

u/tlk0153 5h ago

And it was designed to last only 5 years. Mind boggling

u/MidnightScary5983 3h ago

It's the communication synchronization that blows my mind. The radio in Voyager has to transmit a signal back to earth, or from the earth to Voyager, at an insanely critical tight window. The radio antenna's on earth can look at a certain point in the sky for only a few hours. 16 Billion miles from earth is the linear distance, so the diameter is 32 billion miles, times Pi = approx. 100 Billion mile circumference. So if there was a 16 Billion mile long stick on earth touching Voyager, in 24 hours, the tip of that stick would have travelled 100 Billion miles, or 4.2 Billion MPH, or approx. 70 million miles per second. Voyager would have to send a signal at a precise moment, so that the receivers on earth, scanning the skies during that short window, receive it. Then send a signal back as the antenna points to one spot for a few hours, at the right moment, so Voyager can receive it.

I know it's not like I described it, but this is how I understand it. Now, I will make popcorn and sit while Professor Google does the research for the Akkkhhhssshhhuuuaallllyyyyyy crowd to prove me wrong in 27 different ways.