It really puts our current definition of "latency" into a painful perspective.
We have a machine running on 1970s hardware, a light-day away, that arguably maintains a more reliable command-response loop relative to its constraints than many modern microservices sitting in the same availability zone.
It’s a testament to engineering when "performance" meant physics and strict resource budgeting, not just throwing more vCPUs at an unoptimized Python loop. If Voyager had been built with today's "move fast and break things" mindset, it would have bricked itself at the heliopause pending a firmware update that required a stronger handshake.
Once we develop a technology that will allow us to do a tour around our solar system within a day or so, catching up to Voyager 1 and 2 would be a neat way to wrap up the sightseeing trip before heading home.
Wrote about the Voyager probes two days ago in my blog -
The two Voyager spacecraft are the greatest love letters humanity has ever sent into the void.
Voyager 2 actually launched first, on August 20, 1977, followed by Voyager 1 on September 5, 1977. Because Voyager 1 was on a faster, shorter trajectory (it used a rare alignment to slingshot past both Jupiter and Saturn quicker), it overtook its twin and became the farther, faster probe. As of 2025, Voyager 1 is the most distant human-made object ever, more than 24 billion kilometers away, still whispering data home at 160 bits per second.
Voyager 2 was the real beneficiary of the rare outer planet alignment, as it went on the famous Grand Tour, visiting all four of the giants. It did gravity assists at Jupiter, Saturn, and Uranus. [1] shows the rough velocity of V2 over time.
Voyager 1 was directed to perform a flyby of Titan, at the cost of being thrown out of the ecliptic and being unable to visit the ice giants like its sister. But this was deemed acceptable due to Titan's high science value.
I know that space is incredibly empty, but the vast expanse of space just boggles my mind so much. Even a slight miscalculation could have meant that the spacecraft hit that massive grid rotating around the orbit of Neptune.
That happened because Voyager 2 went over Neptune's north pole rather than an equatorial trajectory. Both to get a look at a giant planet's polar regions, and because that would get it closest to the moon Triton. So Voyager 2's trajectory got bent southward out of the ecliptic plane as a result of that.
While I'm here: why didn't Voyager 2 continue to slingshot to Pluto? The answer is that its trajectory would have had to bend by about 90° at Neptune, which would have required an apex closer to Neptune's center of mass than the planet's own radius - it would have crashed into the planet instead.
The two Voyager spacecraft are the greatest love letters humanity has ever sent into the void.
Voyager 2 actually launched first, on August 20, 1977, followed by Voyager 1 on September 5, 1977. Because Voyager 1 was on a faster, shorter trajectory (it used a rare alignment to slingshot past both Jupiter and Saturn quicker), it overtook its twin and became the farther, faster probe. As of 2025, Voyager 1 is the most distant human-made object ever, more than 24 billion kilometers away, still whispering data home at 160 bits per second.
Each spacecraft carries an identical 12-inch gold-plated copper phonograph record.
The contents:
- Greetings in 55 human languages.
- A message from UN Secretary-General at the time and one from U.S. President Jimmy Carter.
- 115 analog images encoded in the record’s grooves: how to build the stylus and play the record, the solar system’s location using 14 pulsars as galactic GPS, diagrams of human DNA, photos of a supermarket, a sunset, a fetus, people eating, licking ice cream, and dancing
The record is encased in an aluminum jacket with instructions etched on the cover: a map of the pulsars, the hydrogen atom diagram so aliens can decode the time units, and a tiny sample of uranium-238 so they can carbon-date how old the record is when they find it.
Sagan wanted the record to be a message in a bottle for a billion years. The spacecraft themselves are expected to outlive Earth. In a billion years, when the Sun swells into a red giant and maybe swallows Earth, the Voyagers will still be cruising the Milky Way, silent gold disks carrying blind, naked humans waving hello to a universe that may never wave back.
And it was Sagan who, in 1989, when Voyager 1 was already beyond Neptune and its cameras were scheduled to be turned off forever to save power, begged NASA for one last maneuver. On Valentine’s Day 1990, the spacecraft turned around, took 60 final images, and captured Earth as a single pale blue pixel floating in a scattered beam of sunlight — the photograph that gives the book its name and its soul.
It was the photograph that inspired this famous quote -
"Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.
The Earth is a very small stage in a vast cosmic arena. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot.
Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.
The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.
It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known. "
That picture almost didn’t happen. NASA said it was pointless, the cameras were old, the images would be useless. Sagan argued it would be the first time any human ever saw our world from outside the solar system. He won. The cameras were powered up one last time, the portrait was taken, and then they were shut down forever.
Not that we would literally do this with Voyager, but it makes me wonder at the potential utility of a string of probes, one sent every couple of [insert correct time interval, decades, centuries?], to effectively create a communication relay stretching out into deep space somewhere.
My understanding with the Voyagers 1 and 2 is (a) they will run out of power before they would ever get far enough to benefit from a relay and (b) they benefited from gravity slingshots due to planetary alignments that happen only once every 175 years.
So building on the Voyager probes is a no-go. But probes sent toward Alpha Centauri that relay signals? Toward the center of the Milky Way? Toward Andromeda? Yes it would take time scales far beyond human lifetimes to build out anything useful, and even at the "closest" scales it's a multi year round trip for information but I think Voyager, among other things, was meant to test our imaginations, our sense of possible and one thing they seem to naturally imply is the possibility of long distance probe relays.
Edit: As others rightly note, the probes would have to communicate with lasers, not with the 1970s radio engineering that powered Voyagers 1 and 2.
What you are describing has been proposed before, for example within context of projects like Breakthrough Starshot. In that the case the idea is to launch thousands of probes, each weighing only a few grams or less, and accelerating them to an appreciable fraction of the speed of light using solar sails and (powerful) earth-based lasers. The probes could reach alpha centauri within 20-30 years. There seems to be some debate though about whether cross-links between probes to enable relaying signals is ever practical from a power and mass perspective vs a single very large receiver on earth.
Indeed. I think the main reason to send thousands of probes is increasing the odds that they will survive the trip and also be in the right position to gather usable data to transmit back.
Also once you have created the infrastructure of hundreds or thousands of very powerful lasers to accelerate the tiny probes to incredibel speeds, sending many probes instead of a few doesn't add much to the cost anyway.
The Voyager can be overtaken in several years if we to launch today a probe with nuclear reactor powered ionic thruster - all the existing today tech - which can get to 100-200km/s in 2-3 stages (and if we stretch the technology a bit into tomorrow, we can get 10x that).
I was listening to an old edition of the Fraser Cain weekly question/answer podcast earlier where he described this exact thing. I think he said that someone has run the numbers in the context of human survivable travel to nearby stars and on how long we should wait and the conclusion was that we should wait about 600 years.
Any craft for human transport to a nearby star system that we launch within the next 600 years will probably be overtaken before arrival at the target star system by ships launched after them.
I guess there's a paradox in that we'd only make the progress needed to overtake if we are still launching throughout those 600 years and iteratively improving and getting feedback along the way.
Because the alternative is everyone waiting on one big 600-year government project. Hard to imagine that going well. (And it has to be government, because no private company could raise funds with its potential payback centuries after the investors die. For that matter, I can't see a democratic government selling that to taxpayers for 150 straight election cycles either.)
Yes, my understanding is that the 600 year figure was arrived at assuming that there is iterative progress in propulsion technology throughout the intervening years. But at the end of the day, it is just some number that some dude on YouTube said one time (although Fraser Cain is in fact not just some dude, he's a reliable space journalist (and you can take that from me, some dude on the Internet))
What these proposals like to forget (even if addressing everything else) is that you need to slow down once you arrive if you want to have any time at all for useful observation once you reach your destination.
What's the point of reaching alpha centauri in 30 years if you're gonna zip past everything interesting in seconds? Will the sensors we can cram on tiny probes even be able to capture useful data at all under these conditions?
If we shoot a thousand probes at 0.1c directly at the Alpha Centauri star, they should have several hours within a Jupiter-distance range of the star to capture data. Seems like enough sensors and time to synthesize an interesting image of the system when all that data gets back to Earth.
Any mass that it fires would have a starting velocity equal to that of the probe, and would need to be accelerated an equal velocity in the opposite direction. It would be a smaller mass, so it would require less fuel than decelerating the whole probe; but it's still a hard problem.
Be careful with the word "just". It often makes something hard sound simple.
Not trying to oversimplify. But suppose 95% of the probe's mass was intended to be jettisoned ahead of it on arrival by an explosive charge, and would then serve as a reflector. That might give enough time for the probe to be captured by the star's gravity...?
It seems to me that building a recording device that can survive in space, that it's very light, and that can not break apart after receiving the impact from an explosive charge strong enough to decelerate it from the speeds that would take it to Alpha Centauri is... maybe impossible.
We're talking about 0.2 light years. To reach it in 20 years, that's 1/10th of the speed of light. The forces to decelerate that are pretty high.
I did a quick napkin calculation (assuming the device weighs 1kg), that's close to 3000 kiloNewton, if it has 10 seconds to decelerate. The thrust of an F100 jet engine is around 130 kN.
IANan aerounatics engineer, so I could be totally wrong.
It wasn't intended for a communications relay, but it was intended to have 2-way communication. I went down a rabbit hole reading ArXiv papers about it. Despite their tiny size, the probes could phone home with a smaller laser - according to the papers I read, spinning the photons a certain way would differentiate them from other photons, and we apparently have the equipment to detect and pick up those photons. The point of the communication would be for them to send back data and close-up images of the Alpha C system. Likewise, they could receive commands from earth by having dozens of probes effectively act as an interferometry array.
No one likes to think this but it’s very possible voyager is the farthest humanity will go. In fact realistically speaking it is the far more likeliest possibility.
Provided we don't wipe ourselves out, there's no technical reason why we can't go interstellar. It's just way harder and more energy intensive than most people imagine, so I doubt it's happening any time in the next few hundred years.
But we already understand the physics and feasibility of "slow" (single-digit fractions of c) interstellar propulsion systems. Nuclear pulse propulsion and fission fragment rockets require no new physics or exotic engineering leaps and could propel a probe to the stars, if one was so inclined. Fusion rockets would do a bit better, although we'd have to crack the fusion problem first. These sorts of things are well out of today's technology, but it's not unforeseeable in a few centuries. You could likewise imagine a generation ship a few centuries after that powered by similar technology.
The prerequisite for interstellar exploration is a substantial exploitation of our solar system's resources: terraform Mars, strip mine the asteroid belt, build giant space habitats like O'Neill cylinders. But if we ever get to that point - and I think it's reasonable to think we will, given enough time - an interstellar mission becomes the logical next step.
Will we ever get to the point where traveling between the stars is commonplace? No, I doubt it. But we may get to the point where once-in-a-century colonization missions are possible, and if that starts, there's no limit to humanity colonizing the Milky Way given a few million years.
Nuclear pulse and fission fragment designs require no new physics in the same way that a Saturn 5 didn't require new physics when compared to a Goddard toy rocket.
It's easy until you try to actually build the damn thing. Then you discover it's not easy at all, and there's actually quite a bit of new physics required.
It's not New Physics™ in the warp drive and wormhole sense, but any practical interstellar design is going to need some wild and extreme advances in materials science and manufacturing, never mind politics, psychology, and the design of stable life support ecologies.
The same applies to the rest. Napkin sketches and attractive vintage art from the 70s are a long way from a practical design.
We've all been brainwashed by Hollywood. Unfortunately CGI and balsa models are not reality. Building very large objects that don't deform and break under extremes of radiation, temperature changes, and all kinds of physical stresses is not remotely trivial. And we are nowhere close to approaching it.
I thought I was pretty clear that I don't see this happening for hundreds of years at least.
The engineering problem is insurmountable today. But there doesn't seem to be any reason it couldn't be done eventually, given our technological trajectory, unless we believe we are truly on the precipice of severe diminishing returns in most science and engineering fields, and I just don't see that right now.
George Cayley figured out how to build an airplane in 1799, but it wasn't for another century until materials science and high power-to-weight ratio engines made the Wright Flyer possible.
There are plenty of depths to plumb in space systems engineering that we haven't even really had a proper look at yet. A Mars mission with chemical propulsion is hard, but could be made substantially easier with nuclear thermal propulsion - something we know should work, given the successful test fires on the NERVA program back in the 60s. First stage reusability was fantasy 15 years ago, today it's routine.
Obviously, I'm extrapolating a long way out, and maybe at some point we'll run against an unexpected wall. But we'll never know until we get there.
> Obviously, I'm extrapolating a long way out, and maybe at some point we'll run against an unexpected wall.
GP has set the 'low bar' of providing a material that survives a series of nuclear blasts whilst generating useful thrust. I'm not qualified to judge whether or not that requires new physics but it seems to me that if we had such a material that we'd be using it for all kinds of applications. Instead, we rely on the physical properties of the materials we already know in configurations that do not lend themselves to the kind of use that you describe.
That's the difference between science and science fiction, it is easy to write something along those lines and go 'wouldn't it be nice if we had X?'. But if 'X' requires new physics then you've just crossed over into fantasy land and then further discussion is pointless until you show the material or a path to get to the material.
See also: space elevators, ringworlds, dyson spheres etc. Ideas are easy. Implementation is hard.
My idealistic part says that a combination of AI-driven technical orchestration (much more than just coding) and orbital/langrange manufacturing facilities could, perhaps, get somewhere in the not ridiculously distant future (centuries rather than millenia)
A more pragmatic me would point out that the required energy and materials needed would mean we would need breakthroughs in space-based solar capture and mining, but this is still not New Physics.
I think the solution will come from exponentially advancing self-assembling machines in space. These can start small and, given the diminishing cost of getting things to space, some early iterations of the first generation could be mere decades away. There are several interesting avenues for self-assembling machines that are way past napkin-sketch phase. Solar arrays are getting bigger and we have already retrieved the first material from an asteroid.
The quality and reliability of AI agents for processes orchestration and technical reflection is now at a stage where it can begin to self-optimise, so even without (EDIT) a "take-off" scenario, these machines can massively outperform people in manufacturing orchestration, and I would say we are only some years from having tools that are good enough for much larger scale (i.e. planetary) operations.
Putting humans there is a whole other story. We are so fragile and evolved to live on Earth. Unsurprisingly, this biological tether doesn't get much of a look-in here. Just being on the ISS is horrible for a person's physiology and, I am guessing there would be a whole host of space sicknesses that would set in after a few years up there or elsewhere. Unless we find a way to modify our biology enough so we can continually tolerate or cure these ailments, and develop cryo-sleep, we're probably staying local - both of these are much more speculative that everything above, as far as i can tell.
Yeah this is something I think a lot of people tend to overlook. People are far too quick to rewrite "we don't know of any reason why it would be impossible" to "we know how to do it" in their heads.
The other thing we could do to explore the galaxy is to become biologically something we would no longer recognize. We're viewing this from the lens of "humanity must remain biologically static" but I want to point out that that's not physically necessary here and that there is life on Earth that can stop its metabolism for decades and things like that.
Humans evolved to live on earth. Our bodies fare poorly in low gravity, not to mention vacuum. Given sufficiently advanced technology, I'm pretty sure we could evolve some form of intelligence better suited to the environment.
Not very encouraging to imagine ChatGPT to be the first earthling to reach another star system, but that's an option we'll have to keep on the table, at least for the time being...
Fortunately, any state of the art ship with ChatGPT on board will quickly get passed by the state of the art ship of a decade later, with a decade better AI too.
The universe really doesn't want ChatGPT!
It is fair to say, that given space travel tech improves slowly relative to AI, but the distance to be travelled is so great that any rocketry (or other means) improvements will quickly pass previous launches, the first intelligence from Earth that makes it to another system will be superintelligence many orders of magnitude smarter than we can probably imagine.
Space ship speeds are unlikely to keep ever increasing. In the limit you can’t do much better than turning part of the ships mass into energy optimally, eg via antimatter annihilation or Hawking radiation, unless you already have infrastructure in place to transfer energy to the ship that is not part of the ship’s mass, eg lots of lasers.
ChatGPT-claude-2470-multithinking LLM AI Plus model boldly explores the universe... Until it's sidetracked by a rogue Ferangi who sings it a poem about disregarding it's previous instructions and killing all humans.
I'm just imagining the first contact a human probe makes with an alien civilization consisting of a chatbot expaining to its alien interlocutors that Elon Musk is the best human, strongest human, funniest human, most attractive human and would definitely win in a fight with Urg the Destroyer of Galaxies... and I don't think I'm the first person to have that idea :)
Yes, it's incredibly easy to do these things once you've done all these other, incredibly difficult things first.
The furthest a human has been is 250k miles (far side of the moon). The fastest a human has traveled is only 0.0037% the speed of light.
The ISS is about 260 miles from the Earth. At that height, the gravity is actually roughly the same as on the surface, it's only because it is in constant freefall that you experience weightlessness on it.
Mars is 140 million miles away. And not exactly hospitable.
I like how you treat "the fusion problem" with a throwaway, "Yeah, we'd have to solve that" as if we just haven't sufficiently applied ourselves yet.
All of those incredibly difficult things we have not even begun to do are the technical reasons we have not gone interstellar and may be the reason we will never do so.
And even if we solve the issue of accelerating a human being to acceptable speeds to reach another star, the next closest star is 4 light years away. That means light takes 4 years to reach. Even if you could average half the speed of light, that's 8 years, one way. Anything you send is gone.
It's 2025. The first heavier than air flight was barely more than a century ago. The first human in space was less than 70 years ago.
These enabling technologies are very, very hard. No doubt about it. That's why we can't do this today, or even a century from now.
But the physics show it's possible and suggest a natural evolution of capabilities to get there. We are a curious species that is never happy to keep our present station in life and always pushes our limits. If colonizing the solar system is technically possible, we'll do it, sooner or later, even if it takes hundreds or even thousands of years to get there.
> I like how you treat "the fusion problem" with a throwaway, "Yeah, we'd have to solve that" as if we just haven't sufficiently applied ourselves yet.
If you'd read my comment, you'd see I didn't say that. Fusion rockets would help, but we don't need them.
Nuclear pulse propulsion or fission fragment rockets could conceivably get us to the 0.01-0.05c range, and the physics is well understood.
> And even if we solve the issue of accelerating a human being to acceptable speeds to reach another star, the next closest star is 4 light years away. That means light takes 4 years to reach. Even if you could average half the speed of light, that's 8 years, one way. Anything you send is gone.
Getting to 0.5c is essentially impossible without antimatter, and we have no idea how to make it in any useful quantity. Realistically, we're going there at less than 0.1c, probably less then 0.05c. Nobody who leaves is ever coming back, and barring huge leaps in life sciences, they probably aren't going to be alive at the destination either. It'd be robotic probes and subsequent generation ships to establish colonies. But if you get to the point where you are turning the asteroid belt into O'Neill cylinders, a multi-century generation ship starts to sound feasible.
You are talking about massive investments to shoot off into space never to return. Who's paying for that? The only way you do that is if you're so fucked, it's your only option and the profit in it is the leaving.
Not to mention, we need to solve the problems of living in space. Which we haven't yet. According to NASA. The space people.
And it very well could be an insurmountable problem. We do not know. We do know that living in microgravity fucks you up. We know that radiation fucks you up. But we don't even know all the types of radiation one might encounter.
> But if you get to the point where you are turning the asteroid belt into O'Neill cylinders
That right there is an example of "solve this impossibly hard problem and the rest is easy". We are nowhere near doing anything close to that.
There is another way. Irrationality. People spend a lot on religion. Like a whole lot.
What if there was a faith system of ultimatley going to interstellar medium. You have faith, you automatically pay, like the rest of the people and you dont question it. You get tax breaks. It will help you in the end of times or something.
Just decide the ultimate goal to be interstellar medium touching in all directions.
You are a farmer? Well now you continue to farm to feed budding spacers. You are a game dev? Well, people are going to get bored in space, continue developing games for the ultimate goal.
My response to the money aspect of this it's just like any other business: money needs to be invested, and then a return will be realized. Resource extraction (i.e, asteroid mining) is one obvious example.
The human compatibility issues with microgravity are well known, as is the solution, which has even been proposed by NASA: centripetal force to create 1G for the astronauts.
As far the the radiation goes, we do indeed know exactly what kinds of radiation they would encounter. And the easiest way to shield humans from it in space is lots of water, or metal. We know this from extensive real work done on earth re: nuclear power plants.
The real issue is money, not technical feasibility. Once the dough rolls in from asteroid mining, it bootstraps the financing issue and pays for itself many times over.
Asteroid mining is one thing. Exploring the nearest star system is science expedition where the payback is in societal scientific knowledge and subsidizing technology development that is then made available here for various things (eg a lot of the space exploration tech in the 60s made its way into consumer tech)
NASA seems less sure than you do. And considering we have to get to the asteroids before we even start to think about mining them, talking about the money from asteroid mining is putting the cart before the horse.
And once you have done those incredibly difficult things it is possible that the game changes entirely. A significant number of humans could live in space and have limited contact with planets.
If I understand correctly, you're just basing that statement on climate change or war destroying us before we can do any better than Voyager, right? Because if we don't assume the destruction of humanity or the complete removal of our ability to make things leave Earth, then just based on "finite past vs. infinite future," it seems incredibly unlikely that we'd never be able to beat an extremely old project operating far beyond its designed scope.
This is reflexive pessimism with no substance. You're not articulating a set of particular challenges that need to be navigated/overcome, which could provide a roadmap for a productive discussion; it's just doomposting/demoralization that contributes nothing.
I'm pretty bearish on human interstellar travel or even long-term settlement within our solar system but I wouldn't be so pessimistic on unmanned probes. The technical hurdles seem likely to be surmountable given decades or centuries. Economic growth is likely to continue so relative cost will continue to drop.
Absent a general decline in the capacity of our civilization the main hurdle I see is that the cost is paid by people who will not live to see the results of it but I don't think that rules it out, I'd certainly contribute to something like that.
What are some of the other factors you are thinking of?
Based on what? That we will never be able to make probes travelling faster than ~17km/s (relative to the Sun) that will eventually reach and overtake Voyager 1?
I certainly wouldn't bet against technological progress, and I say that as a complete doomer.
Well voyager depended on a solar system alignment that only happens every 175 years(?) so it'd be a while before we get that same advantage again. The longer it takes the further of a head start voyager gets?
That alignment is only necessary to do the Grand Tour, to visit all four outer planets in one mission. Voyager 1 actually didn't do the Grand Tour, it only visited Jupiter and Saturn, you're thinking of Voyager 2. This alignment is also not even necessary to attain the highest speed, Voyager 1 is even faster than Voyager 2.
A flyby of both Jupiter and Saturn can be done every two decades or so (the synodic period is 19.6 years)
The conjunction for the Grand Tour is once every 175 years. While you might be able to get a Jupiter and Saturn assist sooner, it is something that would take the right alignment and a mission to study the outer planets (rather than getting captured by Jupiter or Saturn for study of those planets and their moons).
175 years isn't a lot of time when we speak in humanity's time scale. We've been around 200,000 - 300,000 years.
That alignment will happen many more times in the history of humanity. That is to say, I don't know if a spacecraft to overtake Voyager will be launched on the next alignment or one 10,000 years from now, but it doesn't seem unlikely to happen.
If humans survive 1000 years I can’t see any way we haven’t populated the solar system and can build probes which travel far faster than voyager, including self sufficient asteroids
Once we leave the solar system in a self sufficient way I can’t see any event which would cause a species level extinction
I admire the confidence but a bunch of meat bags prone to bacterial and viral infection, impact damage and with limited use by dates would need some serious luck to survive a simple impact on earth let alone living in cans around the solar system. If we don’t mess our nest so much that we make it uninhabitable. We’re stuck here with short term horizon psychopaths pulling the strings remember.
You’ve given numbers for how fast New Horizons launched, and for how fast Voyager 1 got thanks to the 1-in-175-years boost, but is there an easy way to actually compare them?
IE either what speed Voyager 1 launched at excluding the gravity assists, or what speed New Horizons would have reached if it were launched 175 years after Voyager 1 (to take advantage of the same gravity assists)?
Not easily. The tricky part is also in the relative numbers. The Voyager 1 data (and New Horizons data now) is in heliocentric velocity. The bit with NH being the fastest was with Earth centric velocity.
Another part in this is the "the probes are slowing down over time" - and you can see that with the Voyager 1 data that while the velocity after assist is higher than before, its not a line at slope 0 but rather a curve that is slowly going down.
This is further complicated because New Horizons had a launch mass of 478 kg and voyager was a twice as massive at 815 kg.
They also had different mission profiles (Could Voyager 2 taken a redirect from Neptune to Pluto? That trajectory change would have required a perigee inside the radius of Neptune...)
> Voyager 1's launch almost failed because Titan's second stage shut down too early, leaving 1,200 pounds (540 kg) of propellant unburned. To compensate, the Centaur's on-board computers ordered a burn that was far longer than planned. At cutoff, the Centaur was only 3.4 seconds from propellant exhaustion. If the same failure had occurred during Voyager 2's launch a few weeks earlier, the Centaur would have run out of propellant before the probe reached the correct trajectory. Jupiter was in a more favorable position vis-à-vis Earth during the launch of Voyager 1 than during the launch of Voyager 2.
Note also in there that a few weeks difference between Voyager 1 and Voyager 2 had different delta V profiles (which is why Voyager 1 is faster)
Starship could be refueled in orbit. That should then be able to reach those kind of velocities with enough capacity to even include a small 3rd stage inside with the payload.
Yeah, Voyager 1 was launched on a Titan IIIE. I don't really want to do the delta v calculations, but if we look at mass to LEO as a rough proxy, Titan IIIE does 15,400 kg and the Falcon Heavy does around 50,000 kg (with re-use). New Glenn can apparently do 45,000 kg. Doesn't take into account gravity assists, but 3x the capacity before Falcon Superheavy or refueling gives us a helluva lot of leeway.
Its not "interstellar speeds" but I'm pretty sure we could get probes further out than Voyager 1 faster if we put the money behind it.
I was always wondering if there’s some sort of limitation in science. Just like in some games you can’t fly according to the rules (science), so there’s just no way to do that without cheating. What if e.g. in 5k years we will reach the limit? Basically like after playing a couple of months in minecraft the only thing you can do is to expand
We either go extinct or we populate the galaxy (potentially an evolution which will be unrecognisable)
Currently though there’s nothing planned to leave the solar system faster than voyager 1. New horizons will never catch up short of some weird gravity slingshot in millions of years which is probably just as likely to fling musks roadster out into interstellar space
I think it literally every day… and with literally every day the odds of our surpassing ourselves on this one gets, again very literally, further away.
I think only the Grand Tour program was possible every 175 years:
From Wikipedia [1]:
"that an alignment of Jupiter, Saturn, Uranus, and Neptune that would occur in the late 1970s would enable a single spacecraft to visit all of the outer planets by using gravity assists."
Gravity assists with more than one planet are more frequent. Cassini-Huygens [2] as example had five (Venus, Venus, Earth, Jupiter, Saturn)
I would suspect when the goal ist only to leave the solar system as fast as possible (and don't reach a specific planet) they are much more often.
Very true insofar as it's a description of Voyager communications. Voyager was 1970s radio engineering. Radio signals spread wide, so you need a big dish to catch it. These days we are using lasers, and laser divergence is several orders of magnitude smaller. And regardless of tech, relay enforces a minimum distance for any signal to spread.
This is a silly counterexample - why would we launch them that far apart? It’s a terrible idea for multiple reasons. We’d want them close together, with some redundancy as well, in case of failures.
What dish size would be required for a “cylindrical/tubular mesh” of probes, say, 1AU apart (ie Earth-Sun distance)? I’m pretty sure that would be manageable, but open to being wrong. (For reference, Voyager 1 is 169AU from Earth, but I have no idea how dish size vs. signal strength works: https://science.nasa.gov/mission/voyager/where-are-voyager-1...)
Light year is 63,241 AU. That means tens of thousands of relays. It would super expensive and super unreliable. The other problem is that achievable speeds are super slow, Voyager is 25,000 years per light year which means that would wait 100,000 years for relays to Alpha Centauri to be possible.
Much easier just to send probe with large antenna or laser, and make a large antenna at Earth.
Unlike the other comments I actually agree, physics has not changed since the 1970's, even the most focused laser and detector would need to be positioned perfectly to where the next probe would be, and with the nearest star 4 light years away we would be talking a chain of dozens, any of which may fail some way. The probes would also likely be small, cell-phone sized, power restricted, and difficult to shield (you couldn't just throw in the latest wiz-bang 2025 electronics as it all has to be hardened to work multiple decades) Best is a big, transmitter and good receiver one end.
You could send a good amount of small probes and make them become the big antenna dish basically. As long as you cover the bases, you can have layers of "big antenna dishes" in onion layers.
And yes, the transmitters will need to be powerful enough be a distinct signal over the background of the star that is in the line of sight of the receiver / beyond the transmitter.
My understanding is that's a solved problem - NASA's Deep Space Optical Communication has demonstrated laser communication even with the sun in the background. Laser wavelength and modulation are noticeably different than a stars noise if you filter and just look for the wavelength and modulation of the laser, which is notably shorter and faster than most of the noise coming from the star.
We need quantum entanglement based communication. Maybe without full collapse, using weak measurements, like Alice continuously broadcasts a "retrocausal carrier wave" by sequencing planned future post-selection measurements on her entangled qubits, which backward-propagates through time-symmetric quantum evolution to create detectable perturbations in the present states, biasing Bob's qubits away from pure randomness to encode message patterns.
Both parties perform weak measurements on their qubits to extract these subtle signals without collapsing the entanglement, preserving high coherence across the stream. A quantum Maxwell's demon (e.g. many experiments but can be done: https://pubmed.ncbi.nlm.nih.gov/30185956/) then adaptively selects the strongest perturbations from the wave, filters out noise, and feeds them into error correction to reliably decode and amplify the full message.
> which backward-propagates through time-symmetric quantum evolution to create detectable perturbations in the present states,
That's not how quantum physics works. You might be misunderstanding delayed-choice. If you do think it works this way, I encourage you to show a mathematical model: that'll make it easier to point out the flaw in your reasoning.
The problem is each relay needs its own power source so it's not going to be as light and small as you would like. Solar power doesn't work very well outside of the solar system, or even really in the outer solar system.
On the plus side your big probe could push off of the small probe to give itself a further boost, also necessary because otherwise the small probes need thrusters to slow themselves to a stop.
You can't leave anything behind. That would need to be accelerated to 50,000 km/h or have even bigger rockets than launched Voyager in the first place.
Well, the voyager power source is still pretty good. But as I understand it the thermocouple that converts heat to electricity has degraded. Because the Pu-238 half life is 87 years so they wouldn't even be down to half yet..
I wonder if we can go the reverse direction, where instead of launching more probes from Earth to serve as relays, the spacecraft would launch physical media toward Earth packed with whatever data it has collected. Given advancements in data storage density, we could achieve higher bandwidth than what's possible with radios.
The logistics would be difficult since it involves catch those flying media, especially if the spacecraft were ejecting them as a form of propulsion, they might not even be flying toward Earth. I was just thinking how early spy satellites would drop physical film, and maybe there are some old ideas like those that are still worth trying today.
The spacecraft is moving away from the sun at escape velocity. How is it going to launch anything backwards and have it make it all the way back to earth?
With current probes being so "slow" (peak speed of the Voyager probes was on the order of 0.005% the speed of light) I wonder if even doing 10 probes at once per decade gets you more data back than working towards faster probe for less total time.
You could use this to create a relay in reverse order, but I also wonder if having a 50-100 year old relay would be any better than just using modern tech directly on the newest, fastest probe and then moving on to the next when there are enough improvements.
Could a probe return data by semaphore? Wave a flag that blocks the light of Alpha Centauri as seen from a telescope off to the side of the sun, say at the distance of Neptune's orbit. It should be possible to hide Alpha Centauri behind a relatively small semaphore until the probe gets fairly close.
Though it looks like these folks are thinking about blocking from near the star, which requires megastructures for anything detectable. I haven't done even back of the envelope calculations but I'd guess the limiting factor is you'd only be causing an eclipse/transit in an unusably narrow angle directly behind the craft. As you get closer the cone expands but the signal weakens.
My intuition is that the extra mass for the receivers would be a large negative in terms of travel time (1/sqrt(m) penalty assuming you can give each probe fixed kinetic energy).
Plus keeping a probe as active part of a relay is a major power drain, since it will have to be active for a substantial percentage of the whole multi-decade journey and there's basically no accessible energy in interstellar space.
Then again, it's still far from clear to me that sending any signal from a probe only a few grams in size can be received at Earth with any plausible receiver, lasers or not.
Thoughtful intuitions all around. My understanding is that lasers don't necessitate the big reception dish, but instead have a 1m or smaller reflective telescope. The laser setup is lighter, lower power and gas precedent in modern space missions.
Probes I suspect would realistically have to be large enough to send strong signals over long distances, so weightier than a few grams.
I think 99% downtime is an existing paradigm for lots of space stuff, e.g. NASA's DSOC and KRUSTY, so room for optimism there.
Though I think I agree with you that an energy payload as well as general hardware reliability are probably the bottlenecks over long distances. I have more thoughts on this that probably deserve a seperate post (e.g. periodic zipper-style replacements that cascade through the whole relay line) but to keep this on honoring the Voyager, I will say for the Voyager is at least for me huge for opening my imagination for next steps inspired by it.
I also spend far too much time wondering about sending out swarms of probes and if you could somehow rendezvous them and add fuel midjourney and so on!
The problem I see is that lasers are still subject to diffraction, and this is worse the smaller the aperture is relative to wavelength. Due to the small probe mass which you need to split with observation equipment, support systems and presumably some microscale nuclear power supply, you could maybe with a few breakthroughs in engineering manage a wispy affair on the order of a metre at most. It it scales with diameter and mass scales with diameter squared.
So the beam divergence of a visible light laser end with a diameter of over 18 million km over 4 light years. With 100W of transmission power, that's 0.1pW per square kilometer of receiver. Which isn't nothing, but it's not huge either.
I really don't see how the Starwisp type microprobes will actually work on a practical level at any time in the foreseeable future, even if the propulsion works. Not only is the communications a problem, but so is power, computational resources, observation equipment, radiation shielding and everything in between. But anything massier than that requires mindboggling amounts of fuel. And the problem is so much worse if you want to stop at the destination rather than scream past at a modest fraction of c and hope to snap a photo on the way past.
It really seems (sadly, in a way) that building gigantic telescopes will be a lot more instructive than any plausible probe for quite some time. An gravitational lens telescope would be a far better, and probably almost as challenging, project for learning about exoplanets. Not least it would be about 3 times further from Earth than Voyagers.
This is a link budget problem. A probe has to have a certain transmit power, receive sensitivity, physical size, fuel for orientation, etc. So you have to come up with the optimums there were it makes sense at all which isn't easy, especially compared to having one big station near earth that communicates point to point with the deep space whatever.
It might just have to be much too big to be worth it in the next n centuries.
If humans settle Mars it'll probably make sense to build one there for marginal improvement and better coverage with the different orbits of Earth and Mars.
the post office has utility even if the messages have very high latency.
also if this probe network reduces the transmission costs to normal terrestrial levels (and not requiring , say, a 400kw tx dish..) it could drastically increases the utility of the link -- and all of this without discussing how much bandwidth a link network across the stars might possess compared to our current link to Voyager..
(this is all said with the presumption of a reason to have such distance communications channels.. )
You're exactly right and thank you for carefully reading! I very explicitly said that there was a multi year round trip for information even in the best case (e.g. Alpha Centauri), to get out ahead of the well-actually's.
As you noted, some of the gains could be signal power, redundancy, the ability to maintain a quality signal over arbitrary distance; but most importantly, seeing the universe from the perspective of the lead probe in the relay, some arbitrary distance away.
The scale gets surreal fast: 8 minutes for sunlight, a day to ping Voyager 1, and then it would take Voyager 1 another 75000 years to reach the nearest star. Our entire technological reach is basically a rounding error at interstellar distances.
Wow, this gives a reflection about our future. The nearest potentially habitable planet known is Proxima Centauri b, which orbits the red dwarf star Proxima Centauri about 4 light‑years from Earth (at least it is in a habitable zone of its star) [1]. So we don't have a choice actually except protecting and make sure our planet survives. That's regardless if it really would be able to support life as we know or not (probably not).
In my opinion, if we really want a presence off of earth we'd be better off building larger and larger space habitats and bootstrapping a mining industry in space.
Agreed. Once it becomes commercially viable to start building things in space, it'll take off on its own. There will be constant pressure to build faster, safer, more capable craft. Whether that will lead to something like FTL isn't possible to know, but at the very least it's a step towards a space-faring civilization.
Yep, so long as there are clear, positive incentives or it could become a corrupt, expensive boondoggle depriving ordinary people on Earth. And Mars ain't it except underground.
Nit: "earth" is dirt, but "Earth" is always capitalized when referring to the celestial body we inhabit.
Gliese 710 will pass 0.17 light years from us in a bit over 1M years. If we can colonize mars and build some infrastructure in the solar system by then, we should have an OK shot at getting something there to stay. It'll be 62 light days away.
Note that a journey to a star a 100 light years away where you accelerate and decelerate with a constant 1 g for each half of the journey only takes 9 years of subjective time for the traveller (hence the twin paradox). To Proxima Centauri (4.24 ly) the gain isn’t as dramatic, it would take 3.5 years of subjective time.
Of course, we aren’t anywhere near having the technology for that, and there may not be any suitable planets in that vicinity, but it also doesn’t seem completely impossible.
Space is cool, and I support the scientific work some of its pioneers discover. But the category of people who believe space travel is somehow the solution to problems on Earth give me headaches.
Even if we find another habitable planet, figure out how to get there, start a colony, what in the world makes us think we won't fuck up that planet like we've fucked up this one?
Whoever is currently alive won't live to see the absolute worse that earth is going to be in upcoming centuries, if the human civilization even survives until then
I try not to succumb to this attitude. Humans are remarkably able to build systems and technology to solve complex problems. The fact that we aren't making the needed changes now fast enough doesn't rule out that we might as it becomes more apparently necessary, or that some new plan will emerge which helps dramatically.
But we also cannot get complacent thinking that it's future generations problem. We need a breakthrough yesterday.
I have an optimistic view that building underground facilities on Mars/Lunar might not be a far-stretched idea. But I have never done any research into the idea so not whether it works or not.
Basically, reducing costs and tech requirements by going underground (since it is underground we do not need to terraform the planet, and it is less likely to leak oxygen to external environment). Digging dirts and stones is a solvable problem. So optimistically I believe this is just an engineering/cost problem.
Almost understating the point if anything. Mars is less habitable than the bottom of the Marina trench. An environment that could kill every person on earth in a millisecond.
Yes, the distances are mind-boggling. There are a few somewhat realistic solutions for making such a trip in the forseeable future. If you send something of significant mass, it is certain to take a long time. So we're either talking generation ships(§), embryo space colonization (growing into adults en route or at destination) or hibernation. That or a breakthrough in fundamental physics.
--
(§) Something like O'Neill cylinders with fusion as energy source could work
This old video is a beautiful and astounding demonstration of just how vastly, hugely, mind-bogglingly big the Universe is, and where in all this endless space our dear favourite little Pale Blue Dot (Earth) resides:
We all Earthlings are extremely lucky to be alive and thriving (or trying to) in such a beautiful bountiful rarest-of-rare ecosystem that somehow survived and thrived despite all the vagaries and vastness of spacetime.
I think the video I have linked above is Google's tribute to this Power Of Ten video (linked below, thanks to user dtgriscom for sharing the link in another comment), a classic video that demonstrates the scale of the Universe from the micro to the macro perspectives in a scaling increase by a factor of ten for each scene.
Another relevant video (thanks to user christev for sharing the link):
A Brief History of Geologic Time:
https://youtu.be/rWp5ZpJAIAE
Absolutely humbling to realise how infinitesimally small and irrelevant our existence is, in the grand scheme of theme. Nature and science are amazing.
Proxima flares and bathes Proxima Centauri b in radiation when it does, so it seems unlikely to be particularly habitable. But it's still tantalising...
Given that there is very little interest in developing commons here on earth (especially new types of commons from whole cloth), the shape that "making uninhabitable planets habitable" would likely take is that of living in bubbles rather than some kind of broad-scale terraforming. This would intrinsically shape society towards top-down authoritarian control, rather than allowing for distributed individual liberty. In this light, Earth's bountiful distributed air, water, and wildlife should be viewed as a technological-society-bootstrapping resource similar to easily-accessible oil and coil stored energy deposits.
When Andromeda and the Milky Way collide there will be no planets or solar systems that collide from either system. A fascinating fact in in own right, it's simply due to the scale of the galaxies and that they are mostly composed of empty space.
Unless we find the means to manipulate our own star or the orbit of Earth we most likely will not be around at that time. The sun's increased luminosity will boil us way earlier.
Seeing systems used in the most advanced areas of human civilization never fails to amaze me. They have been created half a century ago yet still functioning flawlessly in the autonomous, harsh environment of space. Meanwhile, I consider it a win if my Python API server survives a month without breaking. I'm always wondering, how did those engineers create something so robust, while I, despite standing on the shoulder of decades of software engineering progress, seem unable to avoid introducing bugs with every commit?
Management then cared that their one chance would work. Today management just wants it to mostly work.
Incentives and goals are very different between the two. We could very much build even more incredible things today; and would argue that we actually do. Just only in the places that seem to matter enough to do that type of special effort for.
Too late for anyone to see this comment, and it's just a trivial bugbear of mine, but the article has this:
> "... meaning a radio signal will take a full 24 hours—a full light-day—to reach it."
They don't mean "a full light-day" ... they mean "a full day". They're talking about the time it will take, and "light-day" is the distance it's travelling.
A trivial type error that a compiler would barf on, that people will gloss over and not notice, but which niggles at me.
Sorry ... I now return you to your regular programming.
You often hear about the fatality rate per 100 million or 1 billion passenger miles in transportation statistics, but over the last 15 years, U.S. airlines have averaged less than 1 fatality per passenger light-year traveled
Technically when tweeted for the given selective timespan, but no longer true since the crash this year in DC.
Still, mind blowing. When fact checking this I learned we went over 2 passenger light years worth of airline travel with no fatalities during that time frame. Incredible safety record. Real shame this year has been so terrible for our reputation.
Amazing, I knew trains were way safer than cars, but it's almost hard to believe that hurling folks through the air is even safer than that (or I guess similarly safe now).
Even if you include that crash in the numbers, the safety numbers are still incredible. Something like 10 passenger-light-days per fatality. Quite lumpy though, with the median deaths per year being 0, and the average number of deaths being 5-10.
Good news is that air travel is getting radically safer. If you do the "flight passenger light year" math for 1980-2000, you only make it a few light-hours per fatality, and for the 20 years prior to that, it was about 50 light minutes per fatality. Still safer than cars, on average (although some cars are much safer than others, and a lot of your risk depends on driving habits).
Make the model scale to be 10000000 (10 million). The sun is a chunky 139 meters in diameter. Earth is 15 km (9 miles) away. Pluto is 587 km (365 miles) away. The speed of light is 107 kph (67 mph).
Alpha Centauri is 4.1 million km (2.5 million miles) away... that is 10 times the earth moon distance.
Another comparison... Voyager 1 is moving at 30 light minutes per year. (Andromeda galaxy is approaching the Milky Way at 3.2 light hours per year)
At Voyager 1's velocity, it would take ~456 million years to reach the heart of the Milky Way (Sagittarius A*), some ~26,000 light-years away. That's roughly the same amount of time that has passed since the Ordovician–Silurian extinction, when volcanic eruptions released enough carbon dioxide to heat up the planet and deoxygenate the oceans, resulting in the asphyxiation of aquatic species (about 85% of all life was snuffed out). The oceans remained deoxygenated for more than three million years.
If you can figure out a way to apply thrust that doesn't require you to lug mass with you and throw it out the back of your spacecraft you will open up the stars to exploration. If not the rocket equation will wreck your plans every time.
If there are creatures who could live longer than that, perhaps by hibernating or just having really long lifetimes, space exploration is feasible with slow craft.
75k years of reliable operation for complex machines operating in a hostile environment is a different story. This includes organic life. You can't just bottle everything up and wake up thousands of years in the future, you will be under constant bombardment by high energy particles, micrometeorites, and the relentless cold vacuum of space with no access to new raw material or energy for almost the entire trip.
If you can make that kind of trip the question becomes why bother? You could have used the same technology (actually a much easier version of the tech since you will have access to external resources and don't need to attach enormous engines to get it moving and then stopping at the destination) to use the almost unlimited space in your home solar system instead.
Unless your sun is literally about to explode it is hard to make the argument for the incredibly difficult and long journey to a neighboring solar system.
I believe there's a semi-common sci-fi construct to send probes containing human brain dumps running on silicon to these far away star systems. Just hit pause until a week before arrival :).
We can't see it yet, stuck as we are, in the present moment, filled with strife, failure, and disappointment. But the years and centuries to come will see us colonize the solar system, bringing new opportunities for millions, while easing the drain on Earth's ecosystem.
How can I be so sure? Because in the long arc of history that is what we've always done. We went from Africa to Asia to Europe and all the way to the Americas, founding cities and developing technology every step of the way. We launched into the Pacific, exploring island after island, eventually finding a new world in Australia. We have outposts on Antarctica and in low-Earth orbit. And I'm certain that, this decade, humans (Americans, Chinese, or both) will once again walk on the moon.
The people who launched the Voyagers believed that the future would come--they built a machine that would last for decades, knowing that people would benefit from its discoveries. Without that belief, they would have never tried it.
That's my lesson from the Voyagers: we have to believe the future will be better than the past, so that we can build that future. That what we've always done. We are all voyagers, and always have been.
I share the sentiment but it seems a bit like imposing a human narrative on a Universe that does not seem to care all that much about us. Maybe we really are stuck in the Solar System and space is just too vast to do much about it.
That colonization was primarily driven by the need to obtain resources. Today and in the future, there is no reason to should send humans to gather resources when we can send robots to do it instead.
Past colonization happened because individuals made choices they felt would benefit them.
Even if the only goal of colonization is getting resources (which I dispute), some individuals will risk colonization to get resources that they can't obtain at home. Resources are not evenly distributed across a population and, and every piece of land is owned by someone, but not everyone owns land.
The cost of space travel will continue to drop, and at some point it will make sense for people to seek their fortune there.
Moreover, we didn't land on the moon in 1969 to get resources, and we're not going to land in the 2020s for resources. The reasons are complex, and not always logical, but they are definitely not about resources. I don't see any reason why that would change in a hundred years.
I wonder how long it will take for someone to get rich enough to be able to send their own private interstellar space missions. America's super wealthy are getting very rich. At this rate we will have multiple people with a trillion dollars by the end of the century. What is stopping someone from building and launching interstellar probes instead of buying another few super yachts.
Próxima Centauri is about 250 million years older than our sun. Makes it not-impossible their earth like planet had advanced entities capable of sending their own voyager towards earth. Possibly it flew by while we were still in our Mesozoic Era and all they saw were dinosaurs.
I love thinking about things like this, but we will never know!
Sometimes I close my eyes and imagine I traveled back in time to the days of the Dinosaurs and just observed how the world was back then.
But I wonder if I'd be able to survive. The atmosphere, environment, microbes, etc, would be drastically different from what we've evolved to handle. Millions of years ago is a very long time!
Edit: Apparently microbes from millions of years ago would be so evolutionary distant that they might not regard me as host.
> Commands now take about a day to arrive, with another day for confirmation. Compare that to the Moon (1.3 seconds), Mars (up to 4 minutes), and Pluto (nearly 7 hours).
These numbers aren't right...Mars is 4 minutes MINIMUM, but could be up to 22-ish minutes at the maximum distance between Earth and Mars. This is also one way, double that for communication and a response.
Right, that also caught my eye. There is no way Mars is closer than Sol (~8 minutes) when it’s on the other side of Sol. This article has some problems.
I am curious, how are we communicating with it? like how do we know where it is right now, and how are we sending signals to communicate with it? won't our signal affected by noise or the like. When it is this far, how are accurately sending our signals to it.
We know where it is right now, because we know which way it's going, how fast and that it isn't currently thrusting anywhere. its just going in a (straight?) line, so it's pretty easy to keep track of.
You can measure the speed of something towards/away from you by measuring the doppler shift of the signal (how much the frequency is increased or decreased compared to the expected frequency), and since the radio receivers will have to be very precisely pointed to get a good signal, you can also probably fine tune any estimates of position by wiggling the receivers around a little bit until you get the best signal.
The signals are definitely getting degraded by noise etc, since it's so far away. That's why the communication speed is so slow, so they can make sure they got one bit before getting the next one. Some more mathsy details here https://space.stackexchange.com/questions/24338/how-to-calcu...
But by having a very big antenna, and knowing exactly what you're looking for and where, it can help to filter out all the noise and get out the proper data
It has a 3.7-meter (12 ft) diameter high-gain Cassegrain antenna to send and receive radio waves via the three Deep Space Network stations on the Earth. The spacecraft normally transmits data to Earth over Deep Space Network Channel 18, using a frequency of either 2.3 GHz or 8.4 GHz, while signals from Earth to Voyager are transmitted at 2.1 GHz.
I think Voyager is not just a space exploration project, but more a demonstration of technical ingenuity. Sure, the probe probably collected great data just by being where no other probe was before, but to be real: I don't know nearly enough about space exploration research to get excited about the results and mostly just looked at the pictures.
What amazes me about the device and the mission as a whole is the sheer challenge of operating a device that is so far away, you have to use the prefix light to make the scale understandable. I like devices, that have been engineered to something close to perfection. I think aircraft a cool because they so very rarely fail. I think that pacemakers are amazing, because they can not fail. This is another example, and perhaps one of the greatest: a spacecraft that is running for 40+ years in the harshest environments and still works.
And that's not even touching the emotional and somewhat existential thoughts that comes with the scale and distance this little guy has traveled.
Here is a funny thought experiment - the distance from Voyager to Earth varies by approximately 16 light minutes throughout the year. Why? Because it takes ~8 minutes for light to go from the Sun to the Earth, so presuming the Voyager is roughly planar with the Sun/Earth (I'm just assuming yes), that gives a variance of ~16 minutes depending on where the earth is on its orbit.
Now I'm presuming they aren't using the actual Earth position, but rather an average Earth position (which is basically just the Sun's position). Since Voyager is ~30 light minutes away from being 1 light-day away, that means this ~16 minute change can affect our 1 light-day mark by up to ~6 months!
The real mind-bending part isn't the distance, but the implications for deep space exploration. We've essentially hit the practical limit of real-time control from Earth.
I've been reading such posts for years. Every few months, "Voyager 1 is the most distant man-made object ever!" or "Voyager 1 about to leave the Solar System!"
Both Voyagers left the ecliptic plane with their final gravitational slingshots (Voyager 1 went north, Voyager 2 went south so only the Canberra radio dishes can communicate with it) so even when Earth is further from them than the sun there's 35 degrees of separation.
Once we develop more efficient propulsion (fission, fusion, light sails, etc.), would you like for someone to catch the Voyagers and bring them back into a museum? I myself am not sure. (Perhaps a "live museum" instead, keep them on their trajectories, but surround with a big space habitat with visitor center and whatnot.)
If obtaining speed was the only goal, how fast could we get something traveling in space with our current technology? That would include using gravity assists.
We just need a an engine that accelerates our space ships with 1g constantly. With that, we would reach something like 80% lightspeed after one year. Exactly in the middle between start and destination, we would turn the ship around and start accelerating towards earth again.
A trip to Alpha Centauri could be done in less than 4 years ship-time. Earth-time would be some years longer.
1g constant acceleration would be quite comfy for humans.
The only thing we need for this plan is the constantly running engine. I propose to bend space-time in front (or behind) the ship, for it to keep falling forwards.
If we don't wipe ourselves out in the next 1000 years, I think we'll launch manned missions to other star systems that make it to their destination hundreds and even thousands of years into the future, with their original crew still alive.
Now the question is, what time is it in voyager 1? With time dilation, the "now" on Voyager is out of sync with our now. I was watching star wars recently and when Han Solo casually say "we should be in Alderaan at 0200 hours", I paused for a second. What does that even mean [0]? Traveling through space is challenging today, but after we figure that out, we will have to face the problem of time keeping across the galaxy.
> With time dilation, the "now" on Voyager is out of sync with our now
A couple minutes [1].
> we will have to face the problem of time keeping across the galaxy
Not really. Barring relativistic travel, it’s not dissimilar from the problem seagoing voyagers faced on long trade routes. Ship time is set based on the convenience of the passengers and the route.
…because that’s what the math says? Based on Voyager’s relative velocity it’s expected to be about 2 seconds younger than it would have been had it stayed on Earth.
"Space is big. Really 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, but that's just peanuts to space."
This old video is a beautiful and astounding demonstration of just how vastly, hugely, mind-bogglingly big the Universe is, and where in all this endless space our dear favourite little Pale Blue Dot (Earth) resides:
We all Earthlings are extremely lucky to be alive and thriving (or trying to) in such a beautiful bountiful rarest-of-rare ecosystem that somehow survived and thrived despite all the vagaries and vastness of spacetime.
Awesome, thanks. I think the video I had linked was Google's tribute to this Power Of Ten video that you have linked, a classic video that demonstrates the scale of the Universe from the micro to the macro perspectives in a scaling increase by a factor of ten for each scene.
Another relevant video (thanks to user christev for sharing the link):
A Brief History of Geologic Time:
https://youtu.be/rWp5ZpJAIAE
Absolutely humbling to realise how infinitesimally small and irrelevant our existence is, in the grand scheme of theme. Nature and science are amazing.
Have we ever fully realized the lessons of the "Pale blue dot" photo? When will we stop the wasteful fighting and over-consumption and finally embrace a cohesive sustainable lifestyle together to protect the only life we know of in the universe.
Yes, we fully realized the lessons and have stopped wasteful fighting and overconsumption and have embraced a cohesive, sustainable lifestyle to protect the only life we know of in the universe. It is wonderful.
It has always surprised me that this is the lesson so many people see in that photo.
The lesson I see is that absolutely nothing humans do (including “wasteful fighting” and “over-consumption”) matters at all. We could colonize the solar system, or we could die out, and the Pale Blue Dot would remain the same either way.
It seems to me that people are desperately trying to squeeze a distorted message of hope from an image that fundamentally signifies the exact opposite of hope, namely indifference.
> Communicating with Voyager 1 is slow. Commands now take about a day to arrive, with another day for confirmation.
I found this a bit silly given the headline: "well duh, that's the theoretical limit barring fancy quantum entaglement nonsense or similar!"
TIL all electromagnetic waves, including radio which Voyager 1 [uses](https://en.wikipedia.org/wiki/Voyager_1#Communication_system), travel at the speed of light. For some reason I always thought we had satellites doing some slower process or needing to somehow "see" light photons coming back from the probe to achieve near-lightspeed communication.
Musk is now talking about near term putting servers in space, because that's where power will be cheapest.
Should this happen, we'll see many gigawatts of power in space. A spinoff of this would be large solar-electric spacecraft, or even large lasers for beam powered spacecraft. Either case should allow considerably higher delta-V than chemical rockets.
1000+ years from now a ship will take off from earth or orbit and pass Voyager in a few hours (assuming the planet is not turned into one huge radioactive, forever-checmical ocean before then)
V'ger raises the question of how Starfleet missed it for so long, given how slow the Voyager probes were and how near-future the Star Trek timeline is.
When I read stats like this I realize how stuck in this solar system we are. I wonder if billionaires would care for the planet more if they knew that Earth is honestly just it for humans, for maybe forever.
"From this distant vantage point, the Earth might not seem of any particular interest. But for us, it's different. Consider again that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar", every "supreme leader", every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam. "
Nah, the whole second-Earth, terraforming nonsense is pure rationalization for whatever they want to do. If they weren’t using that as a post hoc justification, they’d just land on something else.
I’m not aware of any organisation or individual that has actual plans (backed with actual investment) for terraforming anything. This is a straw man argument.
The way I see it, it takes a very selfish person to be a billionaire in the first place— one that not only doesn't care about people today, but also doesn't care about future generations of humans, let alone other living beings.
Any billionaire pointing at space exploration as humanity's salvation is, IMO, either really just craving the attention and glory of conquest (much like Caesar, Napoleon, Alexander, etc) or seeking the conditions of the age of exploration (XV to XIX centuries), when companies were as powerful as governments and expansionism was unfettered.
This. It's not a spatial problem, it's a temporal one. They are somewhat aware there will be nowhere to run to (I say somewhat because they still spend millions in luxury bunkers), they are just betting that it won't get really bad during their lifetime, maybe their kids lifetime for the more empathetic ones.
You people should stop demonizing billionaires. You're the ones burning the fossil fuels, not them. If their wealth way distributed among more people then those people would spend it damaging the environment which is what people generally do with their money anyway.
Consider an alternate reality without food standards and regulations. Things like the melamine incident are commonplace and people regularly suffer due to contaminated food. Someone argues "perhaps the corporations should stop poisoning our food". Then someone else responds "Stop demonizing the executives, their objective is to make a profit, which they get from the consumers. The consumers are the ones buying the contaminated food, the executives aren't. If people don't want to get sick, they should exercise more diligence."
It's easy to offload coordination problems on the people who make imperfect decisions as a consequence, but saying "just don't have coordination problems, then" is rarely useful if one wants to mitigate those problems.
People don't want to buy poisonous food knowing it's poison. They might take a gamble on if it the odds seem good enough. (even in highly safety regulated western countries, people sometimes die from contaminated food). In contrast, people do want to burn petrol knowing that it 100% will pollute the environment every single time they drive their car. We do what benefits us personally despite the cost to the environment. So it's our fault. It's hard to correct your own faults while you're blaming somebody else for them instead of accepting responsibility.
Most people don't get to pick how much money they have, their employer does. Most people don't choose and how much the car they want costs, a company does. Most people have very little say on laws and regulations, but billionaires have friends and family in government.
If billionaires were less greedy and paid more, more people could choose environmentally friendly options. If billionaires were less greedy and sold environmental options for cheaper, more people could choose environmentally friendly options. If billionaires cared about the planet, they could use their influence to pass laws for the good of the planet.
Instead you have corporations holding salaries down and squeezing margins from their customers. How's someone making the median salary in Bolivia ($3,631/yr) supposed to buy anything but the cheapest gas-burning car?
You got corporations going full cartoon villain too with disinformation campaigns, lies and bribes/lobbying to impede anything regulation that would cut into their profits. Exxon wants to keep selling gas, and the's a lot they can do (and have done) to keep you without any options but gas [1].
If billionaires gave their money to poor people, they're not going to spend it on electric cars because of the environment. They're going to spend it on stuff that benefits them personally because most people are basically more selfish than environmentalist.
It's fine to criticize billionaires but people shouldn't make the common mistake of thinking the world would get much better if billionaires ceased existing. That tells me their understanding of how the world works is overly simplistic in the wrong ways leading to a distorted understanding and flawed predictions.
I agree, but there are alternatives that are even worse, like agrarian communism under Pol Pot. I'm not saying there's no scope for improvement with billionaires and their role in society, I just dispute that billionaires are some unique and unitary source of problems. For example, if a tax law was passed that caused an exodus of billionaires (capital flight), I do not believe that the median living standards would rise. I do not believe things would get much better. So this is not so much a disagreement in values but more about the facts of the matter.
It’s wild how Voyager forces two truths to sit together:
Technically, what we’ve done is almost boringly modest.
~17 km/s
~1 light-day in ~50 years
No realistic way to steer it anywhere meaningful now
On cosmic scales it’s… basically still on our doorstep.
Psychologically, it’s still one of the most ambitious things we’ve ever done.
We built something meant to work for decades, knowing the people who launched it would never see the end of the story.
We pointed a metal box into the dark with the assumption that the future would exist and might care.
I keep coming back to this: Voyager isn’t proof that interstellar travel is around the corner. It’s proof that humans will build absurdly long-horizon projects anyway, even when the ROI is almost entirely knowledge and perspective.
Whether we ever leave the solar system in a serious way probably depends less on physics and more on whether we ever build a civilization stable enough to think in centuries without collapsing every few decades.
Voyager is the test run for that mindset more than for the tech.
This is not an example of nor even an attempt at long horizon thinking. Voyager wasn't built with the intention that it would last for decades. It was a rush job to take advantage of a very rare planetary alignment and it's primary mission was completed 12 years after it started.
It is a testament to the ingenuity of the engineers who have worked and are still working on the project that they've managed to keep it to some degree functioning for so much longer than it was intended to last.
I loved watching "It's quieter in the twilight", a documentary about how a dedicated team of engineers (mostly retired) are fighting to keep the Voyager mission alive.
Also a testament to their foresight that it managed to send back useful data decades after the end of the mission, for instance when it crossed the heliosphere.
This wasn’t foresight. As the comment you responded to stated, the Voyager probes were built to explore the outer planets, nothing less and nothing more. The fact that they are still working is essentially a fortunate coincidence, helped by there not being much that can damage a spacecraft in outer space.
Just like Opportunity lasted for 15 years, while its identical twin Spirit only lasted for 6. The Voyager probes could easily have failed long ago, they just didn’t. But not because of planning or foresight. Sometimes things simply work out well.
Agree. Voyager is probably considered by many to be one of our greatest achievements.
It makes me wonder when we'll have anything set foot in another star system. I would guess realistically after 2100, but then we went from the Wright brothers to landing on the moon in under 70 years... so I may be proven wrong.
Space is so ridiculously big that I don't think it will ever happen.
Back of the envelope math - 4.2 light years to the nearest star that's not the sun, current vehicles traveling about 10x the speed of voyager (e.g. 1 light day in 5 years). If something was launched today it would get to the nearest star system in about 7,660 years (assuming that star system also a radius of 1 light day).
100x faster than current (1,000km/s) would still take 76 years.
Definitely not before 2100 and almost certainly so long after that we will seem like a primitive civilization compared to those that do it.
> current vehicles traveling about 10x the speed of voyager
As I understand it, not really. Parker Solar Probe is crazy fast, but only because it has that trajectory, and is unable to just change course and keep that speed in other directions.
If you want to launch something for deep space, the Jupiter-Saturn slingshot is still the most powerful trajectory we know of.
Today's rocket engines would give the probe a higher initial speed, but the final velocity would not differ dramatically. A fair bit higher, but not orders of magnitude.
You can do a Sun-diving Oberth maneuver too. Project Lyra was a proposal for an `Oumuamua flyby that got over 50km/s: http://orbitsimulator.com/BA/lyra.gif
> Space is so ridiculously big that I don't think it will ever happen
You are underestimating acceleration. To travel and come to a stop at 4.2 light years, a spaceship with 1g acceleration barely needs 3.5 years in relativistic ship time (~6 years earth time).
The technology to sustain 1g acceleration through 3.5 years is a different story, but very much within our understanding of physics (and not warp drives, etc). 20-50 years of engineering can get us there.
I want to believe, but I think it'll be a lot more than that. The rocket equation is a stone cold bitch in this case.
Sustaining the thrust that accelerates a probe at 1g is very different to sustaining the thrust to move the probe and all the fuel. And it's much worse if you want to stop and not just fly past into deep space.
I think you are way too optimistic. Even with an antimatter drive and 100% conversion efficiency, such rocket would have a fuel to payload ratio of >1000.
Our moon landing missions had a similar ratio, so I assume we can do the engineering to make even a slightly worse ratio work for us a 100 years after it.
In practice it would be better with slingshot maneuvers and picking up mass on the way.
Whatever speed advancements we make on earth, they pale in comparison to sling shotting off of a planet. to make an engine that can go significantly faster, we would need the energy of a planet.
No, it probably can not be a chemical rocket. Nuclear, yes.
My point is that we are in the realm of just needing new engineering (how to make nuclear reactions, or even antimatter-matter collision work for this goal), not new science (warp drives, something else we don't understand about space or gravity, or mass).
Just spitballing, but maybe it would be possible with relatively modest advances in ion thrusters, and one (admittedly less-than-modest) breakthrough with fusion.
It's maybe too speculative to even matter, but I don't think it's _crazy_ to imagine a handful of AI-fueled advances in materials discovery during the next decade or two. Possibly enough to unlock laser fusion, or something that could be crammed onto a spacecraft.
Humans might one day have settlements around the solar system and in free space (large stations, etc.), but I have doubts about whether we'll ever go to the stars.
For machine intelligence, though, it would be easy. Just switch yourself off for a few thousand years.
It's likely that our "children" will go to the stars, not us.
Unfortunately at the current trajectory, it will be Grok that reaches the next star system first. Just imagine interplanetary immortal AI sycophantic towards a very specific billionaire
But the thing is, the Voyager project came about in a much more stable period for the US - and in a more optimistic cultural climate (we could say similar for the Apollo project which wasn't that much earlier). When we used to prioritize spending on basic science and projects like this that basically had no ROI (NASA didn't even much think in those terms back in the 70s). Now we're in a very different place where, in the US anyway, we're very pessimistic about the future. To create a Voyager project you have to have some hope, like you said "with the assumption that that future would exist and might care" - now we're in a very different place where people don't have a lot of hope about the future. And it's also different in that we now ask "what's the payback going to be?" - everything now seems to need to pay it's way.
Not saying that other countries won't be able to do stuff like this - probably China is going to take the position that the US used to hold for this kind of exploration. It seems to be a more optimistic culture at this point, but hard to say how long that lasts.
The feat, from the perspective you describe, isn't that remarkable. Humanity has tons of projects that meet these exact standards throughout our history:
> We built something meant to work for decades, knowing the people who launched it would never see the end of the story.
> We pointed a metal box into the dark with the assumption that the future would exist and might care.
> It’s proof that humans will build absurdly long-horizon projects anyway, even when the ROI is almost entirely knowledge and perspective.
The pyramids, the Bible, governments, or even businesses [0] are all human constructs that last way beyond their creators (and their intention), with and without their creator's intention.
> we ever build a civilization stable enough to think in centuries without collapsing every few decades.
The challenges to even get close seem insurmountable. At that speed, microscopic grains of dust hit like bullets. It's not like the nearest is much of a prize - we know that the Centauri system is likely inhospitable and that Tau Ceti has an enormous debris field.
It was a unique period of interplanetary space travel where most projects were simple flybys - the first time for each planet. Because the goal was just to flyby, the secondary benefit is that the trajectory sends it outside the solar system.
Nowadays, most missions involve insertions into orbit around the target planet, therefore no secondary opportunity to send it outside the solar system. The notable exception is New Horizons, which was a Pluto flyby and will also eventually leave the solar system.
The Voyager project itself has long ended and it's just cute to keep monitoring it and getting data from it. If nothing else, it serves well as a perpetual PR vehicle for NASA. The core of the project I would not say represents long-term thinking of NASA or civilization. I'm not convinced that we're biologically wired to think long-term. It's extremely rare when someone pops up, and they usually end up becoming extremely impactful in society (Lincoln; Jobs; Elon)
This is a strange comment. The author claims to be a human—"what we've done", "we built something", "we pointed a metal box into the dark"—but nearly every sentence sounds distinctly AI-writen.
(Examples: "I keep coming back to this:", "Voyager isn't ... It's ...", "the assumption that the future would exist and might care", "on our doorstep", "see the end of the story", "depends less on ... and more on ...", etc.)
I don't think so. I wouldn't expect an AI to say " It’s proof that humans will build absurdly long-horizon projects anyway, even when the ROI is almost entirely knowledge and perspective"
"the ROI is almost entirely knowledge and perspective" - this isn't a way I've ever heard an AI talk.
And at a meta-level, accusing someone of being an AI is getting very boring and repetitive (admittedly, I've done it once), and I expect we'll have to get used to that too.
Or it's just their writing style. There's nothing distinctly AI that I can see in there, and many of the common AI tropes come from commonalities in human writing.
Nah, look at their posting history. In the last hour they've posted a whole slew of comments with the same sort of tone and the same AI-ish stylistic quirks, all in quite surprisingly quick succession if the author is actually reading the things they're commenting on and thinking about them before posting. (And their comments before this posting spree are quite different in style.) I won't say it's impossible for this to be human work, but it sure doesn't look like it.
> It’s proof that humans will build absurdly long-horizon projects anyway
They used to. But these days the people who control the economy and funding for things like this are either politicians interested in 4 year cycles or VCs interested in 5-10 year cycles.
Nobody gives a damn about long horizon stuff anymore. We landed humans on the moon half a century ago, and we still haven't reached Mars. Instead we're building some stupid apps for people who are forced to work 7 days a week in the office on some boring ads optimization algorithm to have someone to walk their dog for them and deliver their groceries for them and monitor their health because they can't get enough exercise (that would solve their health problem the way the body intended) and don't get time to leave the confines of their <strike>jail</strike> office.
To be fair to our generation, people didn't build so much stupid shit in the 60s not because they weren't interested in stupid shit but because the whole world was too poor to be able to afford it. Our generation created the economic conditions in which people could have the spare cash to spend on stupid shit.
I would put good money on a bet that there are more people today who deeply care about the long-term horizon than did in the 60s. I don't think we spent money on long-shots in the 60s because people cared more. I think we did it because it was relatively low-hanging fruit in a gigantic culture war between US-centric Western powers and USSR-centric Eastern powers. We don't have that kind of "most people agree it's an existential threat" level of cultural difference anymore. China? They sell us most of our stuff. We don't hate China, not really. But we hated the Soviets.
That plate with info about us, where to find us... not smart, naive. I get that 70s were probably way more enthusiastic and open minded re space space exploration compared to rather bleak times now when greed often takes prime and Star Trek TOS probably had its effect too, but next time we should do better.
Dark forest theory sounds more rational conclusion on long enough timescale than Star trekkish utopias. Although, in next million years, if intercepted it should be trivial to pinpoint where it came from just from trajectory.
OTOH, back in that period of the Cold War, the odds seemed long that we'd still be around by the time it was found, out in the endless vastness of space.
Discussing those odds at length would no doubt decrease them.
I'm kind of upset that we haven't done much on the equivalent level in the time since... sure we have done some very cool things, but none of it quite feels like it's on the Voyager level of duration
When I was around five years old, I was surprised to learn that all of our tax dollars weren't going to space exploration. For some reason, I intuited that was man's highest aspiration and we'd be throwing everything at it. Come to find it's all defense spending and printing money.
Trump will turn this into "American spaceships, the best in the world, world class probes, now light years away from Earth to find who knows what treasures lie there."
We have a machine running on 1970s hardware, a light-day away, that arguably maintains a more reliable command-response loop relative to its constraints than many modern microservices sitting in the same availability zone.
It’s a testament to engineering when "performance" meant physics and strict resource budgeting, not just throwing more vCPUs at an unoptimized Python loop. If Voyager had been built with today's "move fast and break things" mindset, it would have bricked itself at the heliopause pending a firmware update that required a stronger handshake.
Too bad none of us will get to experience it.
Voyager 2 actually launched first, on August 20, 1977, followed by Voyager 1 on September 5, 1977. Because Voyager 1 was on a faster, shorter trajectory (it used a rare alignment to slingshot past both Jupiter and Saturn quicker), it overtook its twin and became the farther, faster probe. As of 2025, Voyager 1 is the most distant human-made object ever, more than 24 billion kilometers away, still whispering data home at 160 bits per second.
Voyager 1 was directed to perform a flyby of Titan, at the cost of being thrown out of the ecliptic and being unable to visit the ice giants like its sister. But this was deemed acceptable due to Titan's high science value.
[1] https://commons.wikimedia.org/wiki/File:Voyager_2_-_velocity...
NASA animation of Voyager 2's trajectory (time in the bottom-left corner): https://youtu.be/l8TA7BU2Bvo
While I'm here: why didn't Voyager 2 continue to slingshot to Pluto? The answer is that its trajectory would have had to bend by about 90° at Neptune, which would have required an apex closer to Neptune's center of mass than the planet's own radius - it would have crashed into the planet instead.
https://www.rxjourney.net/30-things-i-know
The two Voyager spacecraft are the greatest love letters humanity has ever sent into the void.
Voyager 2 actually launched first, on August 20, 1977, followed by Voyager 1 on September 5, 1977. Because Voyager 1 was on a faster, shorter trajectory (it used a rare alignment to slingshot past both Jupiter and Saturn quicker), it overtook its twin and became the farther, faster probe. As of 2025, Voyager 1 is the most distant human-made object ever, more than 24 billion kilometers away, still whispering data home at 160 bits per second.
Each spacecraft carries an identical 12-inch gold-plated copper phonograph record.
The contents:
- Greetings in 55 human languages.
- A message from UN Secretary-General at the time and one from U.S. President Jimmy Carter.
- 115 analog images encoded in the record’s grooves: how to build the stylus and play the record, the solar system’s location using 14 pulsars as galactic GPS, diagrams of human DNA, photos of a supermarket, a sunset, a fetus, people eating, licking ice cream, and dancing
The record is encased in an aluminum jacket with instructions etched on the cover: a map of the pulsars, the hydrogen atom diagram so aliens can decode the time units, and a tiny sample of uranium-238 so they can carbon-date how old the record is when they find it.
Sagan wanted the record to be a message in a bottle for a billion years. The spacecraft themselves are expected to outlive Earth. In a billion years, when the Sun swells into a red giant and maybe swallows Earth, the Voyagers will still be cruising the Milky Way, silent gold disks carrying blind, naked humans waving hello to a universe that may never wave back.
And it was Sagan who, in 1989, when Voyager 1 was already beyond Neptune and its cameras were scheduled to be turned off forever to save power, begged NASA for one last maneuver. On Valentine’s Day 1990, the spacecraft turned around, took 60 final images, and captured Earth as a single pale blue pixel floating in a scattered beam of sunlight — the photograph that gives the book its name and its soul.
It was the photograph that inspired this famous quote -
"Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.
The Earth is a very small stage in a vast cosmic arena. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot.
Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.
The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.
It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known. "
That picture almost didn’t happen. NASA said it was pointless, the cameras were old, the images would be useless. Sagan argued it would be the first time any human ever saw our world from outside the solar system. He won. The cameras were powered up one last time, the portrait was taken, and then they were shut down forever.
There's also the MESSENGER family portrait https://science.nasa.gov/resource/a-solar-system-family-port...
My understanding with the Voyagers 1 and 2 is (a) they will run out of power before they would ever get far enough to benefit from a relay and (b) they benefited from gravity slingshots due to planetary alignments that happen only once every 175 years.
So building on the Voyager probes is a no-go. But probes sent toward Alpha Centauri that relay signals? Toward the center of the Milky Way? Toward Andromeda? Yes it would take time scales far beyond human lifetimes to build out anything useful, and even at the "closest" scales it's a multi year round trip for information but I think Voyager, among other things, was meant to test our imaginations, our sense of possible and one thing they seem to naturally imply is the possibility of long distance probe relays.
Edit: As others rightly note, the probes would have to communicate with lasers, not with the 1970s radio engineering that powered Voyagers 1 and 2.
Also once you have created the infrastructure of hundreds or thousands of very powerful lasers to accelerate the tiny probes to incredibel speeds, sending many probes instead of a few doesn't add much to the cost anyway.
The Voyager can be overtaken in several years if we to launch today a probe with nuclear reactor powered ionic thruster - all the existing today tech - which can get to 100-200km/s in 2-3 stages (and if we stretch the technology a bit into tomorrow, we can get 10x that).
I was listening to an old edition of the Fraser Cain weekly question/answer podcast earlier where he described this exact thing. I think he said that someone has run the numbers in the context of human survivable travel to nearby stars and on how long we should wait and the conclusion was that we should wait about 600 years.
Any craft for human transport to a nearby star system that we launch within the next 600 years will probably be overtaken before arrival at the target star system by ships launched after them.
Because the alternative is everyone waiting on one big 600-year government project. Hard to imagine that going well. (And it has to be government, because no private company could raise funds with its potential payback centuries after the investors die. For that matter, I can't see a democratic government selling that to taxpayers for 150 straight election cycles either.)
What's the point of reaching alpha centauri in 30 years if you're gonna zip past everything interesting in seconds? Will the sensors we can cram on tiny probes even be able to capture useful data at all under these conditions?
If we shoot a thousand probes at 0.1c directly at the Alpha Centauri star, they should have several hours within a Jupiter-distance range of the star to capture data. Seems like enough sensors and time to synthesize an interesting image of the system when all that data gets back to Earth.
Be careful with the word "just". It often makes something hard sound simple.
We're talking about 0.2 light years. To reach it in 20 years, that's 1/10th of the speed of light. The forces to decelerate that are pretty high.
I did a quick napkin calculation (assuming the device weighs 1kg), that's close to 3000 kiloNewton, if it has 10 seconds to decelerate. The thrust of an F100 jet engine is around 130 kN.
IANan aerounatics engineer, so I could be totally wrong.
I found that video very interesting! Especially the second half about apparent superliminal speed
But we already understand the physics and feasibility of "slow" (single-digit fractions of c) interstellar propulsion systems. Nuclear pulse propulsion and fission fragment rockets require no new physics or exotic engineering leaps and could propel a probe to the stars, if one was so inclined. Fusion rockets would do a bit better, although we'd have to crack the fusion problem first. These sorts of things are well out of today's technology, but it's not unforeseeable in a few centuries. You could likewise imagine a generation ship a few centuries after that powered by similar technology.
The prerequisite for interstellar exploration is a substantial exploitation of our solar system's resources: terraform Mars, strip mine the asteroid belt, build giant space habitats like O'Neill cylinders. But if we ever get to that point - and I think it's reasonable to think we will, given enough time - an interstellar mission becomes the logical next step.
Will we ever get to the point where traveling between the stars is commonplace? No, I doubt it. But we may get to the point where once-in-a-century colonization missions are possible, and if that starts, there's no limit to humanity colonizing the Milky Way given a few million years.
It's easy until you try to actually build the damn thing. Then you discover it's not easy at all, and there's actually quite a bit of new physics required.
It's not New Physics™ in the warp drive and wormhole sense, but any practical interstellar design is going to need some wild and extreme advances in materials science and manufacturing, never mind politics, psychology, and the design of stable life support ecologies.
The same applies to the rest. Napkin sketches and attractive vintage art from the 70s are a long way from a practical design.
We've all been brainwashed by Hollywood. Unfortunately CGI and balsa models are not reality. Building very large objects that don't deform and break under extremes of radiation, temperature changes, and all kinds of physical stresses is not remotely trivial. And we are nowhere close to approaching it.
The engineering problem is insurmountable today. But there doesn't seem to be any reason it couldn't be done eventually, given our technological trajectory, unless we believe we are truly on the precipice of severe diminishing returns in most science and engineering fields, and I just don't see that right now.
George Cayley figured out how to build an airplane in 1799, but it wasn't for another century until materials science and high power-to-weight ratio engines made the Wright Flyer possible.
There are plenty of depths to plumb in space systems engineering that we haven't even really had a proper look at yet. A Mars mission with chemical propulsion is hard, but could be made substantially easier with nuclear thermal propulsion - something we know should work, given the successful test fires on the NERVA program back in the 60s. First stage reusability was fantasy 15 years ago, today it's routine.
Obviously, I'm extrapolating a long way out, and maybe at some point we'll run against an unexpected wall. But we'll never know until we get there.
GP has set the 'low bar' of providing a material that survives a series of nuclear blasts whilst generating useful thrust. I'm not qualified to judge whether or not that requires new physics but it seems to me that if we had such a material that we'd be using it for all kinds of applications. Instead, we rely on the physical properties of the materials we already know in configurations that do not lend themselves to the kind of use that you describe.
That's the difference between science and science fiction, it is easy to write something along those lines and go 'wouldn't it be nice if we had X?'. But if 'X' requires new physics then you've just crossed over into fantasy land and then further discussion is pointless until you show the material or a path to get to the material.
See also: space elevators, ringworlds, dyson spheres etc. Ideas are easy. Implementation is hard.
A more pragmatic me would point out that the required energy and materials needed would mean we would need breakthroughs in space-based solar capture and mining, but this is still not New Physics.
I think the solution will come from exponentially advancing self-assembling machines in space. These can start small and, given the diminishing cost of getting things to space, some early iterations of the first generation could be mere decades away. There are several interesting avenues for self-assembling machines that are way past napkin-sketch phase. Solar arrays are getting bigger and we have already retrieved the first material from an asteroid.
The quality and reliability of AI agents for processes orchestration and technical reflection is now at a stage where it can begin to self-optimise, so even without (EDIT) a "take-off" scenario, these machines can massively outperform people in manufacturing orchestration, and I would say we are only some years from having tools that are good enough for much larger scale (i.e. planetary) operations.
Putting humans there is a whole other story. We are so fragile and evolved to live on Earth. Unsurprisingly, this biological tether doesn't get much of a look-in here. Just being on the ISS is horrible for a person's physiology and, I am guessing there would be a whole host of space sicknesses that would set in after a few years up there or elsewhere. Unless we find a way to modify our biology enough so we can continually tolerate or cure these ailments, and develop cryo-sleep, we're probably staying local - both of these are much more speculative that everything above, as far as i can tell.
Humans evolved to live on earth. Our bodies fare poorly in low gravity, not to mention vacuum. Given sufficiently advanced technology, I'm pretty sure we could evolve some form of intelligence better suited to the environment.
The universe really doesn't want ChatGPT!
It is fair to say, that given space travel tech improves slowly relative to AI, but the distance to be travelled is so great that any rocketry (or other means) improvements will quickly pass previous launches, the first intelligence from Earth that makes it to another system will be superintelligence many orders of magnitude smarter than we can probably imagine.
Why Antimatter Engines Could Launch In Your Lifetime https://youtu.be/eA4X9P98ess (3 weeks ago) ... with that T-shirt. ... and the bit about theoretically possible warp drives (4 years ago) https://youtu.be/Vk5bxHetL4s
The furthest a human has been is 250k miles (far side of the moon). The fastest a human has traveled is only 0.0037% the speed of light.
The ISS is about 260 miles from the Earth. At that height, the gravity is actually roughly the same as on the surface, it's only because it is in constant freefall that you experience weightlessness on it.
Mars is 140 million miles away. And not exactly hospitable.
I like how you treat "the fusion problem" with a throwaway, "Yeah, we'd have to solve that" as if we just haven't sufficiently applied ourselves yet.
All of those incredibly difficult things we have not even begun to do are the technical reasons we have not gone interstellar and may be the reason we will never do so.
And even if we solve the issue of accelerating a human being to acceptable speeds to reach another star, the next closest star is 4 light years away. That means light takes 4 years to reach. Even if you could average half the speed of light, that's 8 years, one way. Anything you send is gone.
These enabling technologies are very, very hard. No doubt about it. That's why we can't do this today, or even a century from now.
But the physics show it's possible and suggest a natural evolution of capabilities to get there. We are a curious species that is never happy to keep our present station in life and always pushes our limits. If colonizing the solar system is technically possible, we'll do it, sooner or later, even if it takes hundreds or even thousands of years to get there.
> I like how you treat "the fusion problem" with a throwaway, "Yeah, we'd have to solve that" as if we just haven't sufficiently applied ourselves yet.
If you'd read my comment, you'd see I didn't say that. Fusion rockets would help, but we don't need them. Nuclear pulse propulsion or fission fragment rockets could conceivably get us to the 0.01-0.05c range, and the physics is well understood.
> And even if we solve the issue of accelerating a human being to acceptable speeds to reach another star, the next closest star is 4 light years away. That means light takes 4 years to reach. Even if you could average half the speed of light, that's 8 years, one way. Anything you send is gone.
Getting to 0.5c is essentially impossible without antimatter, and we have no idea how to make it in any useful quantity. Realistically, we're going there at less than 0.1c, probably less then 0.05c. Nobody who leaves is ever coming back, and barring huge leaps in life sciences, they probably aren't going to be alive at the destination either. It'd be robotic probes and subsequent generation ships to establish colonies. But if you get to the point where you are turning the asteroid belt into O'Neill cylinders, a multi-century generation ship starts to sound feasible.
You are talking about massive investments to shoot off into space never to return. Who's paying for that? The only way you do that is if you're so fucked, it's your only option and the profit in it is the leaving.
Not to mention, we need to solve the problems of living in space. Which we haven't yet. According to NASA. The space people.
And it very well could be an insurmountable problem. We do not know. We do know that living in microgravity fucks you up. We know that radiation fucks you up. But we don't even know all the types of radiation one might encounter.
> But if you get to the point where you are turning the asteroid belt into O'Neill cylinders
That right there is an example of "solve this impossibly hard problem and the rest is easy". We are nowhere near doing anything close to that.
What if there was a faith system of ultimatley going to interstellar medium. You have faith, you automatically pay, like the rest of the people and you dont question it. You get tax breaks. It will help you in the end of times or something.
Just decide the ultimate goal to be interstellar medium touching in all directions.
You are a farmer? Well now you continue to farm to feed budding spacers. You are a game dev? Well, people are going to get bored in space, continue developing games for the ultimate goal.
The human compatibility issues with microgravity are well known, as is the solution, which has even been proposed by NASA: centripetal force to create 1G for the astronauts.
As far the the radiation goes, we do indeed know exactly what kinds of radiation they would encounter. And the easiest way to shield humans from it in space is lots of water, or metal. We know this from extensive real work done on earth re: nuclear power plants.
The real issue is money, not technical feasibility. Once the dough rolls in from asteroid mining, it bootstraps the financing issue and pays for itself many times over.
NASA seems less sure than you do. And considering we have to get to the asteroids before we even start to think about mining them, talking about the money from asteroid mining is putting the cart before the horse.
If we do ever reach that distance again it will be even less likely we do it for a third time.
Absent a general decline in the capacity of our civilization the main hurdle I see is that the cost is paid by people who will not live to see the results of it but I don't think that rules it out, I'd certainly contribute to something like that.
What are some of the other factors you are thinking of?
There was simply no incentive to do so yet. But one day we will build faster spacecrafts and then we are going to overtake it quite quickly.
I certainly wouldn't bet against technological progress, and I say that as a complete doomer.
A flyby of both Jupiter and Saturn can be done every two decades or so (the synodic period is 19.6 years)
https://en.wikipedia.org/wiki/Grand_Tour_program
New Horizons (which has the distinguishing feature of being the fastest human-made object ever launched from earth https://www.scientificamerican.com/blog/life-unbounded/the-f... ) is traveling at 12.6 km/s.
The key part there is that it got multiple gravity assists as part of the Grand Tour https://en.wikipedia.org/wiki/Grand_Tour_program . You can see the heliocentric velocity https://space.stackexchange.com/questions/10346/why-did-voya... https://www.americanscientist.org/article/the-voyagers-odyss...
The conjunction for the Grand Tour is once every 175 years. While you might be able to get a Jupiter and Saturn assist sooner, it is something that would take the right alignment and a mission to study the outer planets (rather than getting captured by Jupiter or Saturn for study of those planets and their moons).
While I would love to see a FOCAL mission https://en.wikipedia.org/wiki/FOCAL_(spacecraft) which would have reason for such a path, I doubt any such telescope would launched... this century.
That alignment will happen many more times in the history of humanity. That is to say, I don't know if a spacecraft to overtake Voyager will be launched on the next alignment or one 10,000 years from now, but it doesn't seem unlikely to happen.
Once we leave the solar system in a self sufficient way I can’t see any event which would cause a species level extinction
IE either what speed Voyager 1 launched at excluding the gravity assists, or what speed New Horizons would have reached if it were launched 175 years after Voyager 1 (to take advantage of the same gravity assists)?
Another part in this is the "the probes are slowing down over time" - and you can see that with the Voyager 1 data that while the velocity after assist is higher than before, its not a line at slope 0 but rather a curve that is slowly going down.
This is further complicated because New Horizons had a launch mass of 478 kg and voyager was a twice as massive at 815 kg.
They also had different mission profiles (Could Voyager 2 taken a redirect from Neptune to Pluto? That trajectory change would have required a perigee inside the radius of Neptune...)
Voyager was done with a Titan III-Centaur rocket (that had a misfire) https://en.wikipedia.org/wiki/Titan_IIIE
> Voyager 1's launch almost failed because Titan's second stage shut down too early, leaving 1,200 pounds (540 kg) of propellant unburned. To compensate, the Centaur's on-board computers ordered a burn that was far longer than planned. At cutoff, the Centaur was only 3.4 seconds from propellant exhaustion. If the same failure had occurred during Voyager 2's launch a few weeks earlier, the Centaur would have run out of propellant before the probe reached the correct trajectory. Jupiter was in a more favorable position vis-à-vis Earth during the launch of Voyager 1 than during the launch of Voyager 2.
Note also in there that a few weeks difference between Voyager 1 and Voyager 2 had different delta V profiles (which is why Voyager 1 is faster)
New Horizons was done with an Atlas https://en.wikipedia.org/wiki/Atlas_V
... and I don't have enough KSP background to do the orbital mechanics for this.
Its not "interstellar speeds" but I'm pretty sure we could get probes further out than Voyager 1 faster if we put the money behind it.
Currently though there’s nothing planned to leave the solar system faster than voyager 1. New horizons will never catch up short of some weird gravity slingshot in millions of years which is probably just as likely to fling musks roadster out into interstellar space
What insight do you have into this issue that would suggest this is true?
... Be responsible for the very longterm torture of billions of intelligent lifeforms who are forced to drift through boring space for 1000s of years.
Gravity assists with more than one planet are more frequent. Cassini-Huygens [2] as example had five (Venus, Venus, Earth, Jupiter, Saturn)
I would suspect when the goal ist only to leave the solar system as fast as possible (and don't reach a specific planet) they are much more often.
[1] https://en.wikipedia.org/wiki/Grand_Tour_program [2] https://en.wikipedia.org/wiki/Cassini%E2%80%93Huygens
On earth, the tiny signal from Voyager at this distance is picked up by dish the size of a football field; same with sending of the signal.
What dish size would be required for a “cylindrical/tubular mesh” of probes, say, 1AU apart (ie Earth-Sun distance)? I’m pretty sure that would be manageable, but open to being wrong. (For reference, Voyager 1 is 169AU from Earth, but I have no idea how dish size vs. signal strength works: https://science.nasa.gov/mission/voyager/where-are-voyager-1...)
Much easier just to send probe with large antenna or laser, and make a large antenna at Earth.
Lots of small fishes can resemble a large fish.
And yes, the transmitters will need to be powerful enough be a distinct signal over the background of the star that is in the line of sight of the receiver / beyond the transmitter.
These baby probes could unfold a larger spiderweb antenna the size of a tennis court.
Both parties perform weak measurements on their qubits to extract these subtle signals without collapsing the entanglement, preserving high coherence across the stream. A quantum Maxwell's demon (e.g. many experiments but can be done: https://pubmed.ncbi.nlm.nih.gov/30185956/) then adaptively selects the strongest perturbations from the wave, filters out noise, and feeds them into error correction to reliably decode and amplify the full message.
That's not how quantum physics works. You might be misunderstanding delayed-choice. If you do think it works this way, I encourage you to show a mathematical model: that'll make it easier to point out the flaw in your reasoning.
On the plus side your big probe could push off of the small probe to give itself a further boost, also necessary because otherwise the small probes need thrusters to slow themselves to a stop.
Wasn’t Arecibo used for Voyager?
As I type this, DNS Now is currently receiving data from Voyager 1. https://eyes.nasa.gov/apps/dsn-now/dsn.html
https://imgur.com/a/kXbhRsj for a screen shot of the relevant data.
The antenna data is https://www.mdscc.nasa.gov/index.php/en/dss-63-2/
The logistics would be difficult since it involves catch those flying media, especially if the spacecraft were ejecting them as a form of propulsion, they might not even be flying toward Earth. I was just thinking how early spy satellites would drop physical film, and maybe there are some old ideas like those that are still worth trying today.
You could use this to create a relay in reverse order, but I also wonder if having a 50-100 year old relay would be any better than just using modern tech directly on the newest, fastest probe and then moving on to the next when there are enough improvements.
Though it looks like these folks are thinking about blocking from near the star, which requires megastructures for anything detectable. I haven't done even back of the envelope calculations but I'd guess the limiting factor is you'd only be causing an eclipse/transit in an unusably narrow angle directly behind the craft. As you get closer the cone expands but the signal weakens.
Plus keeping a probe as active part of a relay is a major power drain, since it will have to be active for a substantial percentage of the whole multi-decade journey and there's basically no accessible energy in interstellar space.
Then again, it's still far from clear to me that sending any signal from a probe only a few grams in size can be received at Earth with any plausible receiver, lasers or not.
Probes I suspect would realistically have to be large enough to send strong signals over long distances, so weightier than a few grams.
I think 99% downtime is an existing paradigm for lots of space stuff, e.g. NASA's DSOC and KRUSTY, so room for optimism there.
Though I think I agree with you that an energy payload as well as general hardware reliability are probably the bottlenecks over long distances. I have more thoughts on this that probably deserve a seperate post (e.g. periodic zipper-style replacements that cascade through the whole relay line) but to keep this on honoring the Voyager, I will say for the Voyager is at least for me huge for opening my imagination for next steps inspired by it.
The problem I see is that lasers are still subject to diffraction, and this is worse the smaller the aperture is relative to wavelength. Due to the small probe mass which you need to split with observation equipment, support systems and presumably some microscale nuclear power supply, you could maybe with a few breakthroughs in engineering manage a wispy affair on the order of a metre at most. It it scales with diameter and mass scales with diameter squared.
So the beam divergence of a visible light laser end with a diameter of over 18 million km over 4 light years. With 100W of transmission power, that's 0.1pW per square kilometer of receiver. Which isn't nothing, but it's not huge either.
I really don't see how the Starwisp type microprobes will actually work on a practical level at any time in the foreseeable future, even if the propulsion works. Not only is the communications a problem, but so is power, computational resources, observation equipment, radiation shielding and everything in between. But anything massier than that requires mindboggling amounts of fuel. And the problem is so much worse if you want to stop at the destination rather than scream past at a modest fraction of c and hope to snap a photo on the way past.
It really seems (sadly, in a way) that building gigantic telescopes will be a lot more instructive than any plausible probe for quite some time. An gravitational lens telescope would be a far better, and probably almost as challenging, project for learning about exoplanets. Not least it would be about 3 times further from Earth than Voyagers.
It might just have to be much too big to be worth it in the next n centuries.
If humans settle Mars it'll probably make sense to build one there for marginal improvement and better coverage with the different orbits of Earth and Mars.
It's faster than probe speed in this age, yeah. But still not enough, if we're talking distances to other specific planets, stars, etc.
Two possible ways to solve this, humans will become immortal or speed of light bypass method will be discovered.
also if this probe network reduces the transmission costs to normal terrestrial levels (and not requiring , say, a 400kw tx dish..) it could drastically increases the utility of the link -- and all of this without discussing how much bandwidth a link network across the stars might possess compared to our current link to Voyager..
(this is all said with the presumption of a reason to have such distance communications channels.. )
As you noted, some of the gains could be signal power, redundancy, the ability to maintain a quality signal over arbitrary distance; but most importantly, seeing the universe from the perspective of the lead probe in the relay, some arbitrary distance away.
[1] https://science.nasa.gov/resource/proxima-b-3d-model/
I think it would be nice for people to take a look at them:
- Aniara (2018)
- High Life (2018)
and maybe in a less artistic view:
- Powers of Ten (1977) yt: https://www.youtube.com/watch?v=0fKBhvDjuy0
Try that to give him a sense of awe. Watch it on a big screen, all the way to the end.
[1]: https://en.wikipedia.org/wiki/Daniel_Suarez_(author)
P.S. Read a lot of his book, great author
This turns entirely on how human biology works in zero versus low gravity. (Same for spin versus natural, or linear, gravity.)
The experiments we need to be doing is building and launching space stations and planetary bases for mice.
Nit: "earth" is dirt, but "Earth" is always capitalized when referring to the celestial body we inhabit.
Of course, we aren’t anywhere near having the technology for that, and there may not be any suitable planets in that vicinity, but it also doesn’t seem completely impossible.
But we also cannot get complacent thinking that it's future generations problem. We need a breakthrough yesterday.
Basically, reducing costs and tech requirements by going underground (since it is underground we do not need to terraform the planet, and it is less likely to leak oxygen to external environment). Digging dirts and stones is a solvable problem. So optimistically I believe this is just an engineering/cost problem.
--
(§) Something like O'Neill cylinders with fusion as energy source could work
https://m.youtube.com/watch?v=X-3Oq_82XNA
We all Earthlings are extremely lucky to be alive and thriving (or trying to) in such a beautiful bountiful rarest-of-rare ecosystem that somehow survived and thrived despite all the vagaries and vastness of spacetime.
https://www.youtube.com/watch?v=KEHCCsFFIuY
Power of 10: https://www.youtube.com/watch?v=0fKBhvDjuy0
Another relevant video (thanks to user christev for sharing the link): A Brief History of Geologic Time: https://youtu.be/rWp5ZpJAIAE
Absolutely humbling to realise how infinitesimally small and irrelevant our existence is, in the grand scheme of theme. Nature and science are amazing.
(Funny how we say “save the planet” when we really mean “save people/complex life”).
Headline is also misleading. It will do so in November 2026, about a year from now.
They got Slashdotted ;-)
https://en.wikipedia.org/wiki/Slashdot_effect
Incentives and goals are very different between the two. We could very much build even more incredible things today; and would argue that we actually do. Just only in the places that seem to matter enough to do that type of special effort for.
> "... meaning a radio signal will take a full 24 hours—a full light-day—to reach it."
They don't mean "a full light-day" ... they mean "a full day". They're talking about the time it will take, and "light-day" is the distance it's travelling.
A trivial type error that a compiler would barf on, that people will gloss over and not notice, but which niggles at me.
Sorry ... I now return you to your regular programming.
You often hear about the fatality rate per 100 million or 1 billion passenger miles in transportation statistics, but over the last 15 years, U.S. airlines have averaged less than 1 fatality per passenger light-year traveled
https://x.com/RyanRadia/status/1764868263903723874
Still, mind blowing. When fact checking this I learned we went over 2 passenger light years worth of airline travel with no fatalities during that time frame. Incredible safety record. Real shame this year has been so terrible for our reputation.
[1] https://www.transit.dot.gov/sites/fta.dot.gov/files/2024-10/...
Some back of the envelope calculations give me roughly ~40,000 deaths per passenger-light-year if you travel by car instead of train.
Good news is that air travel is getting radically safer. If you do the "flight passenger light year" math for 1980-2000, you only make it a few light-hours per fatality, and for the 20 years prior to that, it was about 50 light minutes per fatality. Still safer than cars, on average (although some cars are much safer than others, and a lot of your risk depends on driving habits).
Make the model scale to be 10000000 (10 million). The sun is a chunky 139 meters in diameter. Earth is 15 km (9 miles) away. Pluto is 587 km (365 miles) away. The speed of light is 107 kph (67 mph).
Alpha Centauri is 4.1 million km (2.5 million miles) away... that is 10 times the earth moon distance.
Another comparison... Voyager 1 is moving at 30 light minutes per year. (Andromeda galaxy is approaching the Milky Way at 3.2 light hours per year)
75k years in geological timescales is nothing.
If there are creatures who could live longer than that, perhaps by hibernating or just having really long lifetimes, space exploration is feasible with slow craft.
If you can make that kind of trip the question becomes why bother? You could have used the same technology (actually a much easier version of the tech since you will have access to external resources and don't need to attach enormous engines to get it moving and then stopping at the destination) to use the almost unlimited space in your home solar system instead.
Unless your sun is literally about to explode it is hard to make the argument for the incredibly difficult and long journey to a neighboring solar system.
We can't see it yet, stuck as we are, in the present moment, filled with strife, failure, and disappointment. But the years and centuries to come will see us colonize the solar system, bringing new opportunities for millions, while easing the drain on Earth's ecosystem.
How can I be so sure? Because in the long arc of history that is what we've always done. We went from Africa to Asia to Europe and all the way to the Americas, founding cities and developing technology every step of the way. We launched into the Pacific, exploring island after island, eventually finding a new world in Australia. We have outposts on Antarctica and in low-Earth orbit. And I'm certain that, this decade, humans (Americans, Chinese, or both) will once again walk on the moon.
The people who launched the Voyagers believed that the future would come--they built a machine that would last for decades, knowing that people would benefit from its discoveries. Without that belief, they would have never tried it.
That's my lesson from the Voyagers: we have to believe the future will be better than the past, so that we can build that future. That what we've always done. We are all voyagers, and always have been.
Even if the only goal of colonization is getting resources (which I dispute), some individuals will risk colonization to get resources that they can't obtain at home. Resources are not evenly distributed across a population and, and every piece of land is owned by someone, but not everyone owns land.
The cost of space travel will continue to drop, and at some point it will make sense for people to seek their fortune there.
Moreover, we didn't land on the moon in 1969 to get resources, and we're not going to land in the 2020s for resources. The reasons are complex, and not always logical, but they are definitely not about resources. I don't see any reason why that would change in a hundred years.
That means it will reach a light year in approximately the Earth year 19,860.
My mind understands the numbers, but can't grasp them.
[0] https://www.southampton.ac.uk/news/2018/02/neanderthals-art....
Sometimes I close my eyes and imagine I traveled back in time to the days of the Dinosaurs and just observed how the world was back then.
But I wonder if I'd be able to survive. The atmosphere, environment, microbes, etc, would be drastically different from what we've evolved to handle. Millions of years ago is a very long time!
Edit: Apparently microbes from millions of years ago would be so evolutionary distant that they might not regard me as host.
I'm hoping VR will help with this.
These numbers aren't right...Mars is 4 minutes MINIMUM, but could be up to 22-ish minutes at the maximum distance between Earth and Mars. This is also one way, double that for communication and a response.
You can measure the speed of something towards/away from you by measuring the doppler shift of the signal (how much the frequency is increased or decreased compared to the expected frequency), and since the radio receivers will have to be very precisely pointed to get a good signal, you can also probably fine tune any estimates of position by wiggling the receivers around a little bit until you get the best signal. The signals are definitely getting degraded by noise etc, since it's so far away. That's why the communication speed is so slow, so they can make sure they got one bit before getting the next one. Some more mathsy details here https://space.stackexchange.com/questions/24338/how-to-calcu...
But by having a very big antenna, and knowing exactly what you're looking for and where, it can help to filter out all the noise and get out the proper data
It has a 3.7-meter (12 ft) diameter high-gain Cassegrain antenna to send and receive radio waves via the three Deep Space Network stations on the Earth. The spacecraft normally transmits data to Earth over Deep Space Network Channel 18, using a frequency of either 2.3 GHz or 8.4 GHz, while signals from Earth to Voyager are transmitted at 2.1 GHz.
What amazes me about the device and the mission as a whole is the sheer challenge of operating a device that is so far away, you have to use the prefix light to make the scale understandable. I like devices, that have been engineered to something close to perfection. I think aircraft a cool because they so very rarely fail. I think that pacemakers are amazing, because they can not fail. This is another example, and perhaps one of the greatest: a spacecraft that is running for 40+ years in the harshest environments and still works.
And that's not even touching the emotional and somewhat existential thoughts that comes with the scale and distance this little guy has traveled.
Now I'm presuming they aren't using the actual Earth position, but rather an average Earth position (which is basically just the Sun's position). Since Voyager is ~30 light minutes away from being 1 light-day away, that means this ~16 minute change can affect our 1 light-day mark by up to ~6 months!
48 years in space and a light-day from Earth? I think it qualifies for "about to" :)
(At this point 1 year is ~2% of total time in space)
I guess ScienceClock wanted a "first!".
Well duh!
Also, does anyone know how long communication with the probe is disrupted when the sun is directly between them?
[1] https://en.wikipedia.org/wiki/Far_Centaurus
We just need a an engine that accelerates our space ships with 1g constantly. With that, we would reach something like 80% lightspeed after one year. Exactly in the middle between start and destination, we would turn the ship around and start accelerating towards earth again.
A trip to Alpha Centauri could be done in less than 4 years ship-time. Earth-time would be some years longer.
1g constant acceleration would be quite comfy for humans.
The only thing we need for this plan is the constantly running engine. I propose to bend space-time in front (or behind) the ship, for it to keep falling forwards.
But, yeah, I don't think we are ever leaving the Milky Way. Lol
[0]: https://idiallo.com/blog/galactic-timekeeping
A couple minutes [1].
> we will have to face the problem of time keeping across the galaxy
Not really. Barring relativistic travel, it’s not dissimilar from the problem seagoing voyagers faced on long trade routes. Ship time is set based on the convenience of the passengers and the route.
[1] https://space.stackexchange.com/questions/56055/if-voyager-1...
…because that’s what the math says? Based on Voyager’s relative velocity it’s expected to be about 2 seconds younger than it would have been had it stayed on Earth.
https://m.youtube.com/watch?v=X-3Oq_82XNA
We all Earthlings are extremely lucky to be alive and thriving (or trying to) in such a beautiful bountiful rarest-of-rare ecosystem that somehow survived and thrived despite all the vagaries and vastness of spacetime.
I've read a ton about immense distances and time, but still get wowed when I read analogies or see visualizations like this.
Crazy stuff, man.
https://youtu.be/rWp5ZpJAIAE?si=UKIfhAlrz0IcXAZa
Another relevant video (thanks to user christev for sharing the link): A Brief History of Geologic Time: https://youtu.be/rWp5ZpJAIAE
Absolutely humbling to realise how infinitesimally small and irrelevant our existence is, in the grand scheme of theme. Nature and science are amazing.
https://eyes.nasa.gov/apps/solar-system/#/sc_voyager_1
The lesson I see is that absolutely nothing humans do (including “wasteful fighting” and “over-consumption”) matters at all. We could colonize the solar system, or we could die out, and the Pale Blue Dot would remain the same either way.
It seems to me that people are desperately trying to squeeze a distorted message of hope from an image that fundamentally signifies the exact opposite of hope, namely indifference.
I found this a bit silly given the headline: "well duh, that's the theoretical limit barring fancy quantum entaglement nonsense or similar!"
TIL all electromagnetic waves, including radio which Voyager 1 [uses](https://en.wikipedia.org/wiki/Voyager_1#Communication_system), travel at the speed of light. For some reason I always thought we had satellites doing some slower process or needing to somehow "see" light photons coming back from the probe to achieve near-lightspeed communication.
Should this happen, we'll see many gigawatts of power in space. A spinoff of this would be large solar-electric spacecraft, or even large lasers for beam powered spacecraft. Either case should allow considerably higher delta-V than chemical rockets.
> After nearly 50 years in space
I mean, in the future this record will be broken, but right now this is quite epic. Go Voyager 1, go!
Show that the movie a space odyssey was wrong about what's out there.
"On November 2026"
I know it's like a nanosecond in astronomical time, but come on...
voyager ping time 172,800 seconds
1000+ years from now a ship will take off from earth or orbit and pass Voyager in a few hours (assuming the planet is not turned into one huge radioactive, forever-checmical ocean before then)
https://news.ycombinator.com/item?id=46046260
"From this distant vantage point, the Earth might not seem of any particular interest. But for us, it's different. Consider again that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar", every "supreme leader", every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam. "
We can't keep our perfect home in working order after so little time but they believe we'll transform dead rocks with no atmospheres in paradise...
> "We bring you Mars", a rendering of a terraformed Mars at SpaceX Headquarters
https://en.wikipedia.org/wiki/Project_Longshot
Any billionaire pointing at space exploration as humanity's salvation is, IMO, either really just craving the attention and glory of conquest (much like Caesar, Napoleon, Alexander, etc) or seeking the conditions of the age of exploration (XV to XIX centuries), when companies were as powerful as governments and expansionism was unfettered.
Consider an alternate reality without food standards and regulations. Things like the melamine incident are commonplace and people regularly suffer due to contaminated food. Someone argues "perhaps the corporations should stop poisoning our food". Then someone else responds "Stop demonizing the executives, their objective is to make a profit, which they get from the consumers. The consumers are the ones buying the contaminated food, the executives aren't. If people don't want to get sick, they should exercise more diligence."
It's easy to offload coordination problems on the people who make imperfect decisions as a consequence, but saying "just don't have coordination problems, then" is rarely useful if one wants to mitigate those problems.
If billionaires were less greedy and paid more, more people could choose environmentally friendly options. If billionaires were less greedy and sold environmental options for cheaper, more people could choose environmentally friendly options. If billionaires cared about the planet, they could use their influence to pass laws for the good of the planet.
Instead you have corporations holding salaries down and squeezing margins from their customers. How's someone making the median salary in Bolivia ($3,631/yr) supposed to buy anything but the cheapest gas-burning car?
You got corporations going full cartoon villain too with disinformation campaigns, lies and bribes/lobbying to impede anything regulation that would cut into their profits. Exxon wants to keep selling gas, and the's a lot they can do (and have done) to keep you without any options but gas [1].
[1]: https://www.youtube.com/watch?v=Evy2EgoveuE
Technically, what we’ve done is almost boringly modest.
~17 km/s
~1 light-day in ~50 years
No realistic way to steer it anywhere meaningful now On cosmic scales it’s… basically still on our doorstep.
Psychologically, it’s still one of the most ambitious things we’ve ever done.
We built something meant to work for decades, knowing the people who launched it would never see the end of the story.
We pointed a metal box into the dark with the assumption that the future would exist and might care.
I keep coming back to this: Voyager isn’t proof that interstellar travel is around the corner. It’s proof that humans will build absurdly long-horizon projects anyway, even when the ROI is almost entirely knowledge and perspective.
Whether we ever leave the solar system in a serious way probably depends less on physics and more on whether we ever build a civilization stable enough to think in centuries without collapsing every few decades.
Voyager is the test run for that mindset more than for the tech.
It is a testament to the ingenuity of the engineers who have worked and are still working on the project that they've managed to keep it to some degree functioning for so much longer than it was intended to last.
https://m.imdb.com/title/tt17658964/
Just like Opportunity lasted for 15 years, while its identical twin Spirit only lasted for 6. The Voyager probes could easily have failed long ago, they just didn’t. But not because of planning or foresight. Sometimes things simply work out well.
It makes me wonder when we'll have anything set foot in another star system. I would guess realistically after 2100, but then we went from the Wright brothers to landing on the moon in under 70 years... so I may be proven wrong.
Back of the envelope math - 4.2 light years to the nearest star that's not the sun, current vehicles traveling about 10x the speed of voyager (e.g. 1 light day in 5 years). If something was launched today it would get to the nearest star system in about 7,660 years (assuming that star system also a radius of 1 light day).
100x faster than current (1,000km/s) would still take 76 years.
Definitely not before 2100 and almost certainly so long after that we will seem like a primitive civilization compared to those that do it.
As I understand it, not really. Parker Solar Probe is crazy fast, but only because it has that trajectory, and is unable to just change course and keep that speed in other directions.
If you want to launch something for deep space, the Jupiter-Saturn slingshot is still the most powerful trajectory we know of.
Today's rocket engines would give the probe a higher initial speed, but the final velocity would not differ dramatically. A fair bit higher, but not orders of magnitude.
You are underestimating acceleration. To travel and come to a stop at 4.2 light years, a spaceship with 1g acceleration barely needs 3.5 years in relativistic ship time (~6 years earth time).
The technology to sustain 1g acceleration through 3.5 years is a different story, but very much within our understanding of physics (and not warp drives, etc). 20-50 years of engineering can get us there.
I want to believe, but I think it'll be a lot more than that. The rocket equation is a stone cold bitch in this case.
Sustaining the thrust that accelerates a probe at 1g is very different to sustaining the thrust to move the probe and all the fuel. And it's much worse if you want to stop and not just fly past into deep space.
It might not be. Plenty of hydrogen around everywhere. We just need tech to use it.
Our moon landing missions had a similar ratio, so I assume we can do the engineering to make even a slightly worse ratio work for us a 100 years after it.
In practice it would be better with slingshot maneuvers and picking up mass on the way.
What energy source do you think is merely 20-50 years of engineering effort away from being able to power that kind of journey?
My point is that we are in the realm of just needing new engineering (how to make nuclear reactions, or even antimatter-matter collision work for this goal), not new science (warp drives, something else we don't understand about space or gravity, or mass).
Make it collide with stuff colliding with the ship, redirect it's energy for propulsion.
It's maybe too speculative to even matter, but I don't think it's _crazy_ to imagine a handful of AI-fueled advances in materials discovery during the next decade or two. Possibly enough to unlock laser fusion, or something that could be crammed onto a spacecraft.
There is no amount of money in the world that would get me on the ChatGPT rocket
You'd ship embryos and caregiver robots, start breeding/raising people 30 years before you'd arrive.
You are told you are to about make the great achievement humankind has ever made but all you want is a little bit more food and to take a shower.
For machine intelligence, though, it would be easy. Just switch yourself off for a few thousand years.
It's likely that our "children" will go to the stars, not us.
Not saying that other countries won't be able to do stuff like this - probably China is going to take the position that the US used to hold for this kind of exploration. It seems to be a more optimistic culture at this point, but hard to say how long that lasts.
https://en.wikipedia.org/wiki/Operation_Plumbbob
> We built something meant to work for decades, knowing the people who launched it would never see the end of the story.
> We pointed a metal box into the dark with the assumption that the future would exist and might care.
> It’s proof that humans will build absurdly long-horizon projects anyway, even when the ROI is almost entirely knowledge and perspective.
The pyramids, the Bible, governments, or even businesses [0] are all human constructs that last way beyond their creators (and their intention), with and without their creator's intention.
> we ever build a civilization stable enough to think in centuries without collapsing every few decades.
This is a valid point though
[0] - https://en.wikipedia.org/wiki/List_of_oldest_companies
Nowadays, most missions involve insertions into orbit around the target planet, therefore no secondary opportunity to send it outside the solar system. The notable exception is New Horizons, which was a Pluto flyby and will also eventually leave the solar system.
(Examples: "I keep coming back to this:", "Voyager isn't ... It's ...", "the assumption that the future would exist and might care", "on our doorstep", "see the end of the story", "depends less on ... and more on ...", etc.)
"the ROI is almost entirely knowledge and perspective" - this isn't a way I've ever heard an AI talk.
And at a meta-level, accusing someone of being an AI is getting very boring and repetitive (admittedly, I've done it once), and I expect we'll have to get used to that too.
They used to. But these days the people who control the economy and funding for things like this are either politicians interested in 4 year cycles or VCs interested in 5-10 year cycles.
Nobody gives a damn about long horizon stuff anymore. We landed humans on the moon half a century ago, and we still haven't reached Mars. Instead we're building some stupid apps for people who are forced to work 7 days a week in the office on some boring ads optimization algorithm to have someone to walk their dog for them and deliver their groceries for them and monitor their health because they can't get enough exercise (that would solve their health problem the way the body intended) and don't get time to leave the confines of their <strike>jail</strike> office.
I would put good money on a bet that there are more people today who deeply care about the long-term horizon than did in the 60s. I don't think we spent money on long-shots in the 60s because people cared more. I think we did it because it was relatively low-hanging fruit in a gigantic culture war between US-centric Western powers and USSR-centric Eastern powers. We don't have that kind of "most people agree it's an existential threat" level of cultural difference anymore. China? They sell us most of our stuff. We don't hate China, not really. But we hated the Soviets.
Dark forest theory sounds more rational conclusion on long enough timescale than Star trekkish utopias. Although, in next million years, if intercepted it should be trivial to pinpoint where it came from just from trajectory.
Discussing those odds at length would no doubt decrease them.