Voyager 1 passed by Saturn in 1980 on my ninth birthday, and my dad had set up TV sets in the house with video he was getting off a satellite feed for my birthday party with a bunch of my friends. We were all very confused as to why he did it, as it wasn't very kid's party like. Only many years later did I get how cool it actually was, and how I will always remember that Voyager event. So... a much belated thanks, dad!
Great story! At first, I got the impression that your dad was receiving a video stream directly from Voyager's signal. Of course, that would be technically impossible, since Voyager 1 requires approx. 70-meter radio telescopes and specialized equipment to obtain data.
So, what was the "satellite feed" mentioned in the story? Was it a regular TV broadcast, or something more internal distributed by NASA?
Born in 81 here. One of my childhood memories is of watching the broadcast of the flyby of Neptune in 89. I believe it was on PBS, or something similar.
I just looked it up, they had something called Neptune at Night that broadcast from midnight to 9AM. I probably caught it in the mornings before school.
I was too young to know what it was. He had some big dish antennas that he was always futzing with, and I'm sure he was using one of those, but I presume it was some kind of relay signal. Unfortunately I'm not a radio guy.
Humanity’s greatest journey so far has only reached the closest world to us: the Moon ... in a universe that stretches endlessly in every direction and is seemingly infinite.
It's kind of wild to think about: we might end up collapsing our own civilization before we ever make it beyond our solar system.
At this point, I suspect the next real explorers won't be us, but probes carrying intelligent machines..our robotic descendants venturing where we can’t.
Many see this as the answer to the Fermi paradox. Any society on the path to being advanced enough to potentially leave their system probably gains the ability to destroy themselves before getting to that point.
If there isn't a good rationale why it'd be applicable to every civilization that has ever arisen, then it isn't a good fermi paradox solution. Otherwise, if even 1%, or 0.1%, don't fall into the same trap, the galaxy still ends up completely colonized.
One (terrifying) option is we are alone. There is no real reason to believe life is abundant in the universe. Even on Earth (the one place we know for sure can support life), life has only occurred once. Life may just be so much more rare than we think is possible.
> Even on Earth (the one place we know for sure can support life), life has only occurred once.
We don't actually know that at all. It could have happened many times and one line won out, it could have been more of a diffuse process than a single event (picture how microbes share genetic material ~freely but even less structured), or there could be a ton of life out there on Earth that's from a completely different tree. We really have very little idea what's living around us.
If there is a different tree of life right here on Earth and we don't know about it, that would cast doubt on our ability to detect life in worlds light years away. Also, if life had multiple false starts here on Earth, that does also suggest that it is very difficult to take hold even on the original Goldilocks planet. The idea that multiple versions of "life" co-developed and became a single strain is quite interesting to consider. I wonder what else needs to be true to support that theory.
> If there is a different tree of life right here on Earth and we don't know about it, that would cast doubt on our ability to detect life in worlds light years away.
Hm, I don't think it does. The problem is vastly different. Here, on Earth the problem is: sift through all of life for some that's different than the rest. A _hard_ problem with how little of microscopic life we've cataloged completely and with how much of the volume of Earth we can't see.
The problem looking for life in the stars is more: find evidence of _any_ life, so radio signals or chemicals that can't reasonably come from anything else but biology. Those are hard as hell, but fundamentally different.
> Also, if life had multiple false starts here on Earth, that does also suggest that it is very difficult to take hold even on the original Goldilocks planet.
That would be interesting. I kind of guess it's less likely than some kind of winner-take-all outcompeting thing, but who knows. Life that we see is just very good at spreading, escaping and holding on tight.
Early as in we may have developed before any other civilizations? That's interesting. We're speculating of course, but what would explain us being the first after so much time – 13.8 billion years?
The universe was very hot in the beginning. It took a while for stars to form. Even longer for planets to form. Even longer for planets to cool down. The early universe was a violent place. Full of destruction. After the protoplanetary disk finally coalesces to planets and when planets finally stopped getting bombarded by meteorites, they could start cooling. In the earlier days of the universe there might have been intelligent life supporting planets wiped out by the chaos of the early universe. We might not be the first. But we might be one of the first. We might be early. The universe might have a bright future ahead of itself in terms of intelligent life. This is all speculation of course.
Now you could still say that surely there have been enough time for some advanced civilizations to form. And I would argue that we don't know that. At least we have not detected them, either due our instruments or unwillingness of the intelligent life to communicate to us.
There are of course many other explanations of the Fermi Paradox. But since its all unknown, its basically pick and choose. I choose to pick the nice option. There are however other nice options :)
https://en.wikipedia.org/wiki/Fermi_paradox#Hypothetical_exp...
Maybe we aren't the first living things to exist in the universe, but the first intelligent ones, and intelligent here meaning creatures with ability to ask these questions and make space probes to explore the universe.
Maybe intelligence isn't always a product of evolution. Even here on Earth, in the, what, 4 billion years history of the planet, humans are the only evolved creatures with intelligence as defined here. Maybe intelligence doesn't always occur.
A lengthy tangentially related post on my blog if you care -
> Even here on Earth, in the, what, 4 billion years history of the planet, humans are the only evolved creatures with intelligence as defined here. Maybe intelligence doesn't always occur.
It is unlikely that other beings becoming intelligent enough to rival us and deny us the supremacy over the planet would ever be allowed. Homo sapiens are believed to have "contributed to" the extinction of several other modern-human-like species (one of them being the Neanderthals). How many other times before could something similar have happened, perhaps far earlier in the evolutionary timeline?
The only way we would allow sufficiently highly intelligent life to develop and flourish is if it is completely subservient to us.
The more entertaining answer from a scifi book. Aliens that developed earlier decided to become isolationist and wanted to stop young civilizations from blasting radio waves at them, so once a civilization became semi-industrialized, they chucked a planet killing rock at them.
We could be late too, it hasn't even been 200 years since we're technologically capable.
The universe is physically big, which means we'd have a hard time finding life even if it was going on at the same time as us, but add time to the equation and it's game over. There could have been a star trek tier civilisation next door that died 1m years ago and we would probably never know
If a civilisation spreads to stars then logically it will continue to spread (no technology or resource problems) and no event - not even super novas - could stop it (as events could only travel at the speed of expansion)
At that point you don’t have a single civilisation , you have thousands of functionally independent civilisations, with numbers increasing all the time. Sure something could wipe out a civ in one star system, but it couldn’t spread to others quickly enough to affect those others.
The most successful civilisations would continue to expand independently over time to take up all the resources in a galaxy.
Unless they found a way to travel faster than light, which means events could spread fast enough to collapse the civilisations.
Any manned mission in the next 100 years or so to the surface of a moon or planet is basically unnecessary and just to show we can. I am not saying this is a bad thing - but much of the reasons we haven't had manned missions is because it isn't worth it. Robots can do most of what we can do already and what they can't we can do remotely. There's really not a great science reason to send people with our current technology. Robots are already the real explorers.
> Humanity’s greatest journey so far has only reached the closest world to us: the Moon ... in a universe that stretches endlessly in every direction and is seemingly infinite.
I've never felt this impulse. To me it's like saying the Earth is 8,000 miles thick but we all chose to live within just a few feet of the surface.
Unsong is extremely amusing to me for some reason. Something about how Scott comes up with reasonably sounding similarities and manages to make those relate to an overall story.
It's already true because implied precision and comparing continuous measurements for equality and all that. It's both pedantic and meaningless to say it's true on (all of) Nov 13 2026 but not true today.
A thousand years ago it was unthinkable we could circumnavigate the globe.
We don’t understand quantum mechanics and we don’t understand gravity. There’s no reason to assume that we won’t find ways to travel the universe, e.g. by manipulating space time. We just don’t know what we don’t know.
If you had to bet based on past achievements, humanity will find a way. Our job is to push the limits as much as we can and build a foundation for future generations.
I once watched one of those videos that was a speeded up example of light leaving the sun and showing the time it takes to get to the various planets. It was boring as hell after just a couple of minutes and that's with light way speeded up. My conclusion is that "light is too damn slow."
There are lots of hypotheses, but this is one of my gut feelings for why there are no aliens in view. It's hard to escape your local solar system.
When will we need more resources than exist here? We'll be mining the sun to run future simulations. Do we need more compute? Seems like we'll just stay inside.
Most life is probably similarly bound up to their origin. That and life is hard by many, many, many hard steps. Earth life is nearly 30% the age of the universe and it took us this long to get here.
It'd be near impossible for aquatic life to have an industrial revolution without aqueous chemistry control. Can't do that when you're stuck inside water. It's also hard to evolve reasoning when you can't see far ahead. Little evolutionary pressure on reasoning over time and distance.
And it's hard to leave water. You need to evolve new eyes and lungs to live on land. And then you need an energy source like O2, which tends not to stick around.
So many reasons.
The distances of space are certainly one holding us back now.
One thing I keep wondering, though, is whether “life” is tied more to the particular chemistry and environment it uses or to its patterns (the abstract information structure that can, in principle, be re-instantiated on different substrates).
If it’s the patterns that matter, do you think it’s actually impossible for those patterns to be transmitted across interstellar distances? Just like a cup of ocean water is packed with DNA, it’s at least conceivable that what we call “cosmic background noise” could, in principle, hide extremely compressed life-patterns that only an advanced civilization could recognize and reconstruct back into something we’d meaningfully call “alive.” And of course, the more efficiently you code that information, the more it statistically has to look like random noise.
Not saying this is likely -- just that if the essence of life is informational rather than chemical, "traveling" could look very different for any life that is suitably advanced.
>It's also hard to evolve reasoning when you can't see far ahead.
I think it was the book Pale Blue Dot by Carl Sagan where he hypothesized aliens living in Venus and how they wouldn't be able to see the stars and other planets because their atmosphere is too thick to see through with visible light and also their perpetual, opaque cloud cover made of sulfuric acid.
He described how everything would change if they managed to just escape their planet for the very first time and see a new world out there that they never even imagined existed. A world more vast and complicated than their brightest minds could have ever thought of.
Probably from deconstructing the solar system's asteroids and planets. I imagine a Dyson sphere would be less structurally sound and harder to get right – due to gravitational forces on the material – than a Dyson swarm or matryoshka brain. The latter made of independent satellites orbiting the sun and collecting light from concentric orbits at various distances.
That is it. When you become very aware of just how amazingly far away everything else is, fighting over a speak of dust and the only home we have seems absolutely ridiculous.
A great long form video on this is "Shouting at stars : A history of interstellar messages". It really highlights just how empty it all is.
https://www.youtube.com/watch?v=uFI5WpK2sgg
If mankind exists in 1000 years time and hasn’t regressed then we’ll be able to build fusion powered self sustaining asteroids. Those can be used as airships to colonise every system in the Milky Way in a few million years.
600M years is enough time for Earth to try two or three attempts at intelegence, with full blown fossil fuel replenishment cycles. It won’t be humans - whether we leave for the stars tomorrow or blow ourselves to bits we’ll have evolved to something unrecognisable by then, but there’s very few things which could end life on earth in the next 200 million years (mainly very large out of system asteroids/rogue planets)
My understanding is that ISS is not self-sustaining even in principle. It consistently needs to be resupplied with water and breathable air as the station continuously leaks it. These resupplies happen about once every month or two. This article goes into quite a few details about what would be needed for actual self-sustainable human space exploration and it looks like there's quite a few engineering challenges to work out.
> Of course we are, but my question is why is that notable?
> You also breathe a nitrogen-oxygen-hydrogen mixture, and have a body that is built to walk around at 1g on a planet between 0-100 degrees F.
> That doesn’t seem to bother people.
Humans like to explore. We've populated the globe from our starting position in East Africa.
When we look to the skies, beyond our own galaxy, and into the early history of the universe, we are seeing a world that will never get to explore first-hand. Humans like to explore.
I mean we have a way today to get to a fraction of light speed with the nuclear bombs for propulsion method. Technically it’s even survivable for a person.
Elite Dangerous is a modern sci-fi space simulation game. It takes place in the 34th century. You can actually visit solar system (can't land on Earth yet), and catch up with two Voyagers. They are where they would be in 1200 years, approximately 25 light days away from the Sun.
I remember as a kid seeing the first photos of Uranus and Neptune from the Voyager probes. What's sad to me is they remain to this day the only time we've ever visited these ice giants. There have been a number of proposals over the years but none have been selected and it seems like 2045-2050 is the soonest we could get to Uranus (more for Neptune) but that pretty much requires a launch by 2034 and we've pretty much run out of time for a mission to be selected to that window given that it would be a complex and expensive flagship mission. I guess it depends on whether it's a flyby (like New Horizons) or an intercept mission, which would take substantially longer.
Obital mechanics are a funny thing however. You see this with the complicated BepiColombo trajectory to Mercury [1] that requires multiple passes on Venus. Mercury orbits at ~48km/s (compared to Earth's 30km/s). Fun fact: the escape velocity of the Sun is 42km/s so it's easier to leave the Solar System than intercept Mercury.
One difficulty is there aren't large gas giants to slingshot or brake around.
Uranus's orbital velocity is ~6.8km/s so it's both really far and requires a ton of delta-V to slow down to intercept.
Anyway, I digress.
So Voyager 1's speed seems to be ~17km/s, I guess relative to the Sun. People talk about the time required for interplanetary (let alone interstellar) travel but we can do much better than this with relatively near-future technology.
We need a whole bunch more Earth-orbit space infrastructure and industry to do anything, really. Lower launch costs in particular. I think this future is orbital rings [2]. This would revolutionize getting stuff into orbit but also launching vehicles to other planets. Basically you accelerate on the inside of the ring at ~2G with magnetic levitation to counter the linear momentum. You can reasonably get ~15km/s with this, adding to the EArth's 30km/s ideally so even without fuel you can get to ~45km/s.
I see China is proposing a fair few missions to the outer system with Jutiper in a few years with Uranus and Neptune to follow. But they are just proposals still, but it is good to see they are at least considering it.
It was more like assimilating everything it encountered in minute detail, but the living beings were no longer "living" as such once assimilated. It was creepy.
It's expected never to encounter any other object in all eternity. Unless of course someone deliberately aims for it. I heard once it will eventually lose it's form entirely and just drift through space as a melted lump of metal. For some reason that reminds me of Red Dwarf.
We are going to lose it before long i wonder if it will be possible to find it on a future date in theory.
I doubt that’s true. At minimum it’s going to hit an enormous quantity of micrometer sized objects.
It’s gravitationally bound to the Milky way so it’s going to keep wandering into and out of star systems for a very long time. We’re talking a large multiple of the age of the universe meanwhile plenty of space rocks show encounters with other space rocks on a vastly smaller timescale. If nothing else it’s got decent odds of being part of the star formation process. Stars are ~10% of the milky way’s mass and star formation is going to continue for a while.
Supposing that it does become part of a new star, and some "nearby" civilization had sufficiently precise instruments...would that be a detectable anomaly? Like some atoms of Plutonium still haven't decayed, and isn't that weird that Plutonium's spectral signature is present in this new star? Or is that just something that happens because some plutonium is created in a supernova and might just have been floating around anyway.
Based on the interstellar density it will take a billion years to ablate just a millimetre off its outer layer.
The chance of impacting anything larger than that is internal, same as an encounter with another star. In 40,000 years it will get to within 1.6 light years from a star, that’s such an unimaginable distance it’s irrelevant.
In 100 million to 1 billion years you may not be able to recover audio from the golden record, but until that point they will be lasting remnants of a civilisation long gone, and never be encountered.
Voyagers will only impact a few thousand kilograms of material before all stars die out in 10^14 years, it will still be an object after the final stars fade.
The biggest risk to voyager now is if proton decay is a thing, or if a civilisation deliberately seeks it out, which seems very unlikely given how many natural lumps of iron int he 1 ton range flying through interstellar space.
“In 40,000 years it will get to within 1.6 light years from a star, that’s such an unimaginable distance it’s irrelevant.”
On most human timescales that’s a long time, but here it’s only 0.004% of a billion years and in general stars are ~5 light years between closest stars in our neighborhood. If you assume zero significant impacts means it’s around in 100+ billion years there will be many vastly closer passes than 1.6 lightyears. It’s the kind of thing you really need to simulate because gravity plays a larger role the closer voyager gets to another star.
Not at light years. How many non-binary stars do we see colliding with other stars. They don’t. Even when andromeda runs into the Milky Way it won’t result in stars colliding. The chance of the sun colliding with another sun is somewhere in the 10^30 range.
Voyager may end up in a solar system briefly as a high speed extra solar object like Oumuamua, but the chance of it being close enough to suffer any physical affect would be small - think how small a target that would be and how rare stars are. To get within 1 light day would mean passing 100,000 stars within one light year. To get down to earth distance is something like 4 billion passes within a 1 light year distance.
Now sure predicting the future beyond say 100 billion years is tricky, and not something you could simulate, but for all intents and purposes the voyagers will continue long after Earth has died. It (and other craft on escape trajectories like new horizons and pioneers) will be the last remnants of human civilisation
Stars hitting stars isn’t the metric a baseball sized object clearly counts as a meaningful collision at these speeds. Add up all objects in terms of 2d cross sections and it’s the small stuff we’re going to care about, but getting near stars matters because from what we can tell there’s so much more small stuff near stars. The Oort Cloud sits 0.03 to 0.08 light years from the sun etc. https://en.wikipedia.org/wiki/Oort_cloud ~5 earth masses in vastly smaller objects is a lot of targets. (I recalled an earlier and far larger estimate but it’s still a lot of material.)
Ignoring gravity may be fine at 1.6 light years but a closer approach to even just say 2 light months means spending thousands of years much closer to the star which would matter here. So simple extrapolation based on random distribution of nearest approaches like you just proposed with that 100,000 star calculation is heavily biased in the wrong direction.
Voyage is travelling about 1 light year per 22,000 years.
That’s really fast on cosmic scales. If it left when the dinosaurs were wiped out it would be 3,000 light years away by now. Even if it left as late as when humans arrived in North America it would be a light year away.
Sure, but we're talking insane amounts of time unless it hits something head one. Even the electronics are still alive and in 2024 after a long break we managed to get signals back. It is anybody's guess at this point how long the craft will remain functional but it will take a long, long time (long after humanity will either have destroyed itself or has figured out how to overtake it) before it is 'a melted lump of metal'.
Look at the metal that we routinely dig up in the hostile environment known as 'Earth' and which wasn't particularly designed to be long lasting. Voyager is just that: designed to last for a really long time. At a minimum several millennia, though of course by that time the electronics will no longer function, and not because they no longer have power but simply because they have degraded due to their rather more sensitive nature than the rest of the craft.
> I heard once it will eventually lose it's form entirely
It will be sitting at something like -450F. Could it really lose form!? Is the idea that all the phonons could converge to one point, shifting an atom of metal (which will happen infinitely with infinite time)? Maybe with random photons/hydrogen/whatever "continuously" adding energy?
One issue is that over long enough timeframes, even atoms that we consider stable will decay - particularly ones that are heavier than iron, which will decay towards iron or nickel. That decay will eventually compromise the structure of the probes.
From what I recall, one of the hazards of long term space travel is that nearly any material will start sublimating atoms in the hard vacuum of space, with things like cosmic rays adding to the woes. Some over time it will start deteriorating.
Not sure about “melting” into an amorphous mass, I guess in theory the probes gravity could do that, but I would imagine even the tiniest force would disturb that and dissipate it.
> It's expected never to encounter any other object in all eternity.
This is read as "near zero" rather than "no chance". "Expected" is a word of uncertainty.
I think the rough napkin math would be: take the volume that the probe will sweep through and multiply it by the volume of matter in the universe/volume of the universe.
Voyager 1 passed by Saturn in 1980 on my ninth birthday, and my dad had set up TV sets in the house with video he was getting off a satellite feed for my birthday party with a bunch of my friends. We were all very confused as to why he did it, as it wasn't very kid's party like. Only many years later did I get how cool it actually was, and how I will always remember that Voyager event. So... a much belated thanks, dad!
Great story! At first, I got the impression that your dad was receiving a video stream directly from Voyager's signal. Of course, that would be technically impossible, since Voyager 1 requires approx. 70-meter radio telescopes and specialized equipment to obtain data.
So, what was the "satellite feed" mentioned in the story? Was it a regular TV broadcast, or something more internal distributed by NASA?
Born in 81 here. One of my childhood memories is of watching the broadcast of the flyby of Neptune in 89. I believe it was on PBS, or something similar.
I just looked it up, they had something called Neptune at Night that broadcast from midnight to 9AM. I probably caught it in the mornings before school.
I was too young to know what it was. He had some big dish antennas that he was always futzing with, and I'm sure he was using one of those, but I presume it was some kind of relay signal. Unfortunately I'm not a radio guy.
Humanity’s greatest journey so far has only reached the closest world to us: the Moon ... in a universe that stretches endlessly in every direction and is seemingly infinite.
It's kind of wild to think about: we might end up collapsing our own civilization before we ever make it beyond our solar system.
At this point, I suspect the next real explorers won't be us, but probes carrying intelligent machines..our robotic descendants venturing where we can’t.
Many see this as the answer to the Fermi paradox. Any society on the path to being advanced enough to potentially leave their system probably gains the ability to destroy themselves before getting to that point.
Short terms issues preventing long term gains.
If there isn't a good rationale why it'd be applicable to every civilization that has ever arisen, then it isn't a good fermi paradox solution. Otherwise, if even 1%, or 0.1%, don't fall into the same trap, the galaxy still ends up completely colonized.
One (terrifying) option is we are alone. There is no real reason to believe life is abundant in the universe. Even on Earth (the one place we know for sure can support life), life has only occurred once. Life may just be so much more rare than we think is possible.
> Even on Earth (the one place we know for sure can support life), life has only occurred once.
We don't actually know that at all. It could have happened many times and one line won out, it could have been more of a diffuse process than a single event (picture how microbes share genetic material ~freely but even less structured), or there could be a ton of life out there on Earth that's from a completely different tree. We really have very little idea what's living around us.
If there is a different tree of life right here on Earth and we don't know about it, that would cast doubt on our ability to detect life in worlds light years away. Also, if life had multiple false starts here on Earth, that does also suggest that it is very difficult to take hold even on the original Goldilocks planet. The idea that multiple versions of "life" co-developed and became a single strain is quite interesting to consider. I wonder what else needs to be true to support that theory.
> If there is a different tree of life right here on Earth and we don't know about it, that would cast doubt on our ability to detect life in worlds light years away.
Hm, I don't think it does. The problem is vastly different. Here, on Earth the problem is: sift through all of life for some that's different than the rest. A _hard_ problem with how little of microscopic life we've cataloged completely and with how much of the volume of Earth we can't see.
The problem looking for life in the stars is more: find evidence of _any_ life, so radio signals or chemicals that can't reasonably come from anything else but biology. Those are hard as hell, but fundamentally different.
> Also, if life had multiple false starts here on Earth, that does also suggest that it is very difficult to take hold even on the original Goldilocks planet.
That would be interesting. I kind of guess it's less likely than some kind of winner-take-all outcompeting thing, but who knows. Life that we see is just very good at spreading, escaping and holding on tight.
That is one answer. Another possibility (the one I prefer, since this is mere speculation anyway) is that we are early.
Early as in we may have developed before any other civilizations? That's interesting. We're speculating of course, but what would explain us being the first after so much time – 13.8 billion years?
The universe was very hot in the beginning. It took a while for stars to form. Even longer for planets to form. Even longer for planets to cool down. The early universe was a violent place. Full of destruction. After the protoplanetary disk finally coalesces to planets and when planets finally stopped getting bombarded by meteorites, they could start cooling. In the earlier days of the universe there might have been intelligent life supporting planets wiped out by the chaos of the early universe. We might not be the first. But we might be one of the first. We might be early. The universe might have a bright future ahead of itself in terms of intelligent life. This is all speculation of course.
https://en.wikipedia.org/wiki/Firstborn_hypothesis https://en.wikipedia.org/wiki/Formation_and_evolution_of_the... https://en.wikipedia.org/wiki/Nebular_hypothesis https://en.wikipedia.org/wiki/Protoplanetary_disk
Now you could still say that surely there have been enough time for some advanced civilizations to form. And I would argue that we don't know that. At least we have not detected them, either due our instruments or unwillingness of the intelligent life to communicate to us.
There are of course many other explanations of the Fermi Paradox. But since its all unknown, its basically pick and choose. I choose to pick the nice option. There are however other nice options :) https://en.wikipedia.org/wiki/Fermi_paradox#Hypothetical_exp...
Maybe we aren't the first living things to exist in the universe, but the first intelligent ones, and intelligent here meaning creatures with ability to ask these questions and make space probes to explore the universe.
Maybe intelligence isn't always a product of evolution. Even here on Earth, in the, what, 4 billion years history of the planet, humans are the only evolved creatures with intelligence as defined here. Maybe intelligence doesn't always occur.
A lengthy tangentially related post on my blog if you care -
https://www.rxjourney.net/extraterrestrial-intelligence-and-...
> Even here on Earth, in the, what, 4 billion years history of the planet, humans are the only evolved creatures with intelligence as defined here. Maybe intelligence doesn't always occur.
It is unlikely that other beings becoming intelligent enough to rival us and deny us the supremacy over the planet would ever be allowed. Homo sapiens are believed to have "contributed to" the extinction of several other modern-human-like species (one of them being the Neanderthals). How many other times before could something similar have happened, perhaps far earlier in the evolutionary timeline?
The only way we would allow sufficiently highly intelligent life to develop and flourish is if it is completely subservient to us.
The more entertaining answer from a scifi book. Aliens that developed earlier decided to become isolationist and wanted to stop young civilizations from blasting radio waves at them, so once a civilization became semi-industrialized, they chucked a planet killing rock at them.
I think that’s the question, is 13.8 billion years a lot of time, of not a lot of time?
Earth (and the solar system) is 4.3B years old, a bit more than a third of that, so it's not really that much time in comparison no?
If you assume the heat death as the end point, we're ridiculously early in the universe's lifespan.
Quite unlikely, but if there is a multiverse, everything is possible.
We could be late too, it hasn't even been 200 years since we're technologically capable.
The universe is physically big, which means we'd have a hard time finding life even if it was going on at the same time as us, but add time to the equation and it's game over. There could have been a star trek tier civilisation next door that died 1m years ago and we would probably never know
If a civilisation spreads to stars then logically it will continue to spread (no technology or resource problems) and no event - not even super novas - could stop it (as events could only travel at the speed of expansion)
At that point you don’t have a single civilisation , you have thousands of functionally independent civilisations, with numbers increasing all the time. Sure something could wipe out a civ in one star system, but it couldn’t spread to others quickly enough to affect those others.
The most successful civilisations would continue to expand independently over time to take up all the resources in a galaxy.
Unless they found a way to travel faster than light, which means events could spread fast enough to collapse the civilisations.
Any manned mission in the next 100 years or so to the surface of a moon or planet is basically unnecessary and just to show we can. I am not saying this is a bad thing - but much of the reasons we haven't had manned missions is because it isn't worth it. Robots can do most of what we can do already and what they can't we can do remotely. There's really not a great science reason to send people with our current technology. Robots are already the real explorers.
> Humanity’s greatest journey so far has only reached the closest world to us: the Moon ... in a universe that stretches endlessly in every direction and is seemingly infinite.
I've never felt this impulse. To me it's like saying the Earth is 8,000 miles thick but we all chose to live within just a few feet of the surface.
Yep. Ghost in the shell. The robots are just the next stage in the evolution of life..
"we might end up collapsing our own civilization before we ever make it beyond our solar system."
Given what I see in the past 15 years, I don't particularly see that as a problem, honestly.
"Some say it has already happened..."
Lol
Both Voyager space probes are way farther away than the moon. Is this a reference I'm not understanding?
Parent poster is considering only crewed journeys, surely.
That's when it collides with the skybox, like the sailboat at the end of The Truman Show.
Or like Apollo 8 in the incredibly funny book Unsong.
Unsong is extremely amusing to me for some reason. Something about how Scott comes up with reasonably sounding similarities and manages to make those relate to an overall story.
David Brin thinks so:
https://en.wikipedia.org/wiki/The_Crystal_Spheres
Supplied headline will be true in 1 year. Actual headline:
Pedantically, will this be one mean solar light-day, or one sidereal light-day?
thanks, title is updated.
It's already true because implied precision and comparing continuous measurements for equality and all that. It's both pedantic and meaningless to say it's true on (all of) Nov 13 2026 but not true today.
I’m not sure your point is warranted given there is a year between today and November 2026. Surely we can be more precise than a year?
We are trapped in the solar system.
A thousand years ago it was unthinkable we could circumnavigate the globe.
We don’t understand quantum mechanics and we don’t understand gravity. There’s no reason to assume that we won’t find ways to travel the universe, e.g. by manipulating space time. We just don’t know what we don’t know.
If you had to bet based on past achievements, humanity will find a way. Our job is to push the limits as much as we can and build a foundation for future generations.
> Our job is to push the limits as much as we can
What if that's exactly what will cause our extinction, you don't know what you don't know am I right ?
But if we don't advance our technology enough to escape this planet, then we'll go extinct for sure, no ifs
In hundred millions of years...
We've been humans for 300k years, we can chill for a couple of centuries, the rush might actually cause our extinction too
I once watched one of those videos that was a speeded up example of light leaving the sun and showing the time it takes to get to the various planets. It was boring as hell after just a couple of minutes and that's with light way speeded up. My conclusion is that "light is too damn slow."
The sky is big!
Yeah, pretty much:
> It will take about 300 years for Voyager 1 to reach the inner edge of the Oort Cloud and possibly about 30,000 years to fly beyond it.
There are lots of hypotheses, but this is one of my gut feelings for why there are no aliens in view. It's hard to escape your local solar system.
When will we need more resources than exist here? We'll be mining the sun to run future simulations. Do we need more compute? Seems like we'll just stay inside.
Most life is probably similarly bound up to their origin. That and life is hard by many, many, many hard steps. Earth life is nearly 30% the age of the universe and it took us this long to get here.
It'd be near impossible for aquatic life to have an industrial revolution without aqueous chemistry control. Can't do that when you're stuck inside water. It's also hard to evolve reasoning when you can't see far ahead. Little evolutionary pressure on reasoning over time and distance.
And it's hard to leave water. You need to evolve new eyes and lungs to live on land. And then you need an energy source like O2, which tends not to stick around.
So many reasons.
The distances of space are certainly one holding us back now.
One thing I keep wondering, though, is whether “life” is tied more to the particular chemistry and environment it uses or to its patterns (the abstract information structure that can, in principle, be re-instantiated on different substrates).
If it’s the patterns that matter, do you think it’s actually impossible for those patterns to be transmitted across interstellar distances? Just like a cup of ocean water is packed with DNA, it’s at least conceivable that what we call “cosmic background noise” could, in principle, hide extremely compressed life-patterns that only an advanced civilization could recognize and reconstruct back into something we’d meaningfully call “alive.” And of course, the more efficiently you code that information, the more it statistically has to look like random noise.
Not saying this is likely -- just that if the essence of life is informational rather than chemical, "traveling" could look very different for any life that is suitably advanced.
>It's also hard to evolve reasoning when you can't see far ahead.
I think it was the book Pale Blue Dot by Carl Sagan where he hypothesized aliens living in Venus and how they wouldn't be able to see the stars and other planets because their atmosphere is too thick to see through with visible light and also their perpetual, opaque cloud cover made of sulfuric acid.
He described how everything would change if they managed to just escape their planet for the very first time and see a new world out there that they never even imagined existed. A world more vast and complicated than their brightest minds could have ever thought of.
Damn, I might need to read some Carl Sagan again!
The resource thing always gets me. More ideas of things like dyson sphere's. Where does the material from them come from?
Probably from deconstructing the solar system's asteroids and planets. I imagine a Dyson sphere would be less structurally sound and harder to get right – due to gravitational forces on the material – than a Dyson swarm or matryoshka brain. The latter made of independent satellites orbiting the sun and collecting light from concentric orbits at various distances.
Yeah we don't even live under the sea, or populate Antarctica.
Those are thousands of times more hospitable than outside earth.
For the next 300-500 years, yes. But there is plenty of things to do, stuff to build and room to expand within a light-day from Sun.
No other place is habitable within a light day of the sun.
A good argument for making sure our planet stays habitable. Caring about the environment isn't just for hippies anymore!
That is it. When you become very aware of just how amazingly far away everything else is, fighting over a speak of dust and the only home we have seems absolutely ridiculous.
A great long form video on this is "Shouting at stars : A history of interstellar messages". It really highlights just how empty it all is. https://www.youtube.com/watch?v=uFI5WpK2sgg
You can't stop fighting the ones who claim the speck of dust (or a pale blue dot) is a flat disk.
Works up until the earth becomes uninhabitable in 600M years, before then humans are going to need to find and colonize a different planet.
If mankind exists in 1000 years time and hasn’t regressed then we’ll be able to build fusion powered self sustaining asteroids. Those can be used as airships to colonise every system in the Milky Way in a few million years.
600M years is enough time for Earth to try two or three attempts at intelegence, with full blown fossil fuel replenishment cycles. It won’t be humans - whether we leave for the stars tomorrow or blow ourselves to bits we’ll have evolved to something unrecognisable by then, but there’s very few things which could end life on earth in the next 200 million years (mainly very large out of system asteroids/rogue planets)
No rush then, modern humans aren't even 1m years old...
Being hippie worked in the 1960ies, a crowd with a similar mindset fared much worse in 1930ies Paris.
ISS is one such place.
My understanding is that ISS is not self-sustaining even in principle. It consistently needs to be resupplied with water and breathable air as the station continuously leaks it. These resupplies happen about once every month or two. This article goes into quite a few details about what would be needed for actual self-sustainable human space exploration and it looks like there's quite a few engineering challenges to work out.
https://www.frontiersin.org/journals/space-technologies/arti...
Not only that but they have to routinely boost its orbital velocity as there is still a little atmospheric drag at the height.
Of course we are, but my question is why is that notable?
You also breathe a nitrogen-oxygen-hydrogen mixture, and have a body that is built to walk around at 1g on a planet between 0-100 degrees F.
That doesn’t seem to bother people.
> Of course we are, but my question is why is that notable?
> You also breathe a nitrogen-oxygen-hydrogen mixture, and have a body that is built to walk around at 1g on a planet between 0-100 degrees F.
> That doesn’t seem to bother people.
Humans like to explore. We've populated the globe from our starting position in East Africa.
When we look to the skies, beyond our own galaxy, and into the early history of the universe, we are seeing a world that will never get to explore first-hand. Humans like to explore.
until next "General Relativity" is discovered, and maybe we can get both voyagers back.
Sandboxed. Yep.
I mean we have a way today to get to a fraction of light speed with the nuclear bombs for propulsion method. Technically it’s even survivable for a person.
Elite Dangerous is a modern sci-fi space simulation game. It takes place in the 34th century. You can actually visit solar system (can't land on Earth yet), and catch up with two Voyagers. They are where they would be in 1200 years, approximately 25 light days away from the Sun.
I remember as a kid seeing the first photos of Uranus and Neptune from the Voyager probes. What's sad to me is they remain to this day the only time we've ever visited these ice giants. There have been a number of proposals over the years but none have been selected and it seems like 2045-2050 is the soonest we could get to Uranus (more for Neptune) but that pretty much requires a launch by 2034 and we've pretty much run out of time for a mission to be selected to that window given that it would be a complex and expensive flagship mission. I guess it depends on whether it's a flyby (like New Horizons) or an intercept mission, which would take substantially longer.
Obital mechanics are a funny thing however. You see this with the complicated BepiColombo trajectory to Mercury [1] that requires multiple passes on Venus. Mercury orbits at ~48km/s (compared to Earth's 30km/s). Fun fact: the escape velocity of the Sun is 42km/s so it's easier to leave the Solar System than intercept Mercury.
One difficulty is there aren't large gas giants to slingshot or brake around.
Uranus's orbital velocity is ~6.8km/s so it's both really far and requires a ton of delta-V to slow down to intercept.
Anyway, I digress.
So Voyager 1's speed seems to be ~17km/s, I guess relative to the Sun. People talk about the time required for interplanetary (let alone interstellar) travel but we can do much better than this with relatively near-future technology.
We need a whole bunch more Earth-orbit space infrastructure and industry to do anything, really. Lower launch costs in particular. I think this future is orbital rings [2]. This would revolutionize getting stuff into orbit but also launching vehicles to other planets. Basically you accelerate on the inside of the ring at ~2G with magnetic levitation to counter the linear momentum. You can reasonably get ~15km/s with this, adding to the EArth's 30km/s ideally so even without fuel you can get to ~45km/s.
[1]: https://www.youtube.com/watch?v=BK3F4fmqtbA
[2]: https://www.youtube.com/watch?v=LMbI6sk-62E
I see China is proposing a fair few missions to the outer system with Jutiper in a few years with Uranus and Neptune to follow. But they are just proposals still, but it is good to see they are at least considering it.
Who remembers the Star Trek movie where one of the voyagers came back as v’ger - the humongous sentient entity of accumulated space junk?
> Who remembers the Star Trek movie where one of the voyagers came back as v’ger - the humongous sentient entity of accumulated space junk?
Everyone.
It was more like assimilating everything it encountered in minute detail, but the living beings were no longer "living" as such once assimilated. It was creepy.
I watched it the first time around in a cinema in West Germany. That was a British cinema in Deutchland - a BFBS jobbie.
Times have changed somewhat!
It's expected never to encounter any other object in all eternity. Unless of course someone deliberately aims for it. I heard once it will eventually lose it's form entirely and just drift through space as a melted lump of metal. For some reason that reminds me of Red Dwarf.
We are going to lose it before long i wonder if it will be possible to find it on a future date in theory.
Its gonna prove the closed manifold hypothesis when it shows up coming from the opposite direction in a few hundred million years
I doubt that’s true. At minimum it’s going to hit an enormous quantity of micrometer sized objects.
It’s gravitationally bound to the Milky way so it’s going to keep wandering into and out of star systems for a very long time. We’re talking a large multiple of the age of the universe meanwhile plenty of space rocks show encounters with other space rocks on a vastly smaller timescale. If nothing else it’s got decent odds of being part of the star formation process. Stars are ~10% of the milky way’s mass and star formation is going to continue for a while.
Supposing that it does become part of a new star, and some "nearby" civilization had sufficiently precise instruments...would that be a detectable anomaly? Like some atoms of Plutonium still haven't decayed, and isn't that weird that Plutonium's spectral signature is present in this new star? Or is that just something that happens because some plutonium is created in a supernova and might just have been floating around anyway.
Based on the interstellar density it will take a billion years to ablate just a millimetre off its outer layer.
The chance of impacting anything larger than that is internal, same as an encounter with another star. In 40,000 years it will get to within 1.6 light years from a star, that’s such an unimaginable distance it’s irrelevant.
In 100 million to 1 billion years you may not be able to recover audio from the golden record, but until that point they will be lasting remnants of a civilisation long gone, and never be encountered.
Voyagers will only impact a few thousand kilograms of material before all stars die out in 10^14 years, it will still be an object after the final stars fade.
The biggest risk to voyager now is if proton decay is a thing, or if a civilisation deliberately seeks it out, which seems very unlikely given how many natural lumps of iron int he 1 ton range flying through interstellar space.
“In 40,000 years it will get to within 1.6 light years from a star, that’s such an unimaginable distance it’s irrelevant.”
On most human timescales that’s a long time, but here it’s only 0.004% of a billion years and in general stars are ~5 light years between closest stars in our neighborhood. If you assume zero significant impacts means it’s around in 100+ billion years there will be many vastly closer passes than 1.6 lightyears. It’s the kind of thing you really need to simulate because gravity plays a larger role the closer voyager gets to another star.
Not at light years. How many non-binary stars do we see colliding with other stars. They don’t. Even when andromeda runs into the Milky Way it won’t result in stars colliding. The chance of the sun colliding with another sun is somewhere in the 10^30 range.
Voyager may end up in a solar system briefly as a high speed extra solar object like Oumuamua, but the chance of it being close enough to suffer any physical affect would be small - think how small a target that would be and how rare stars are. To get within 1 light day would mean passing 100,000 stars within one light year. To get down to earth distance is something like 4 billion passes within a 1 light year distance.
Now sure predicting the future beyond say 100 billion years is tricky, and not something you could simulate, but for all intents and purposes the voyagers will continue long after Earth has died. It (and other craft on escape trajectories like new horizons and pioneers) will be the last remnants of human civilisation
Stars hitting stars isn’t the metric a baseball sized object clearly counts as a meaningful collision at these speeds. Add up all objects in terms of 2d cross sections and it’s the small stuff we’re going to care about, but getting near stars matters because from what we can tell there’s so much more small stuff near stars. The Oort Cloud sits 0.03 to 0.08 light years from the sun etc. https://en.wikipedia.org/wiki/Oort_cloud ~5 earth masses in vastly smaller objects is a lot of targets. (I recalled an earlier and far larger estimate but it’s still a lot of material.)
Ignoring gravity may be fine at 1.6 light years but a closer approach to even just say 2 light months means spending thousands of years much closer to the star which would matter here. So simple extrapolation based on random distribution of nearest approaches like you just proposed with that 100,000 star calculation is heavily biased in the wrong direction.
It's going to hit gas that will slowly but inexorably sputter it to nothing.
'Slowly' is doing a lot of work there. We're talking about very large amounts of time.
Like 10^200 years
In 10^40 years it will barely have scratched the surface. Unless protons decay.
Estimates for sputtering of dust grains are much faster than this.
Granted, there is also growth of dust grains. But surfaces from which atoms can be ejected by UV photons will erode.
Some notes: https://www.astro.princeton.edu/~draine/dust/Draine_IPMU_Lec...
I'm imagining the sun going nova and the Voyagers surfing on that wave...
Voyage is travelling about 1 light year per 22,000 years.
That’s really fast on cosmic scales. If it left when the dinosaurs were wiped out it would be 3,000 light years away by now. Even if it left as late as when humans arrived in North America it would be a light year away.
I wonder where (and in what state) they'll be by then.
I know what state I will be in by then :)
You never know! Maybe at that point all your atoms will have been recycled into a brand new consciousness absorbed into ChatGPT 7.0.
Talk about nightmares...
The Sun will not go nova.
I think I said 'imagine'?
Quite. It will hit the occasional something, eventually. If nothing else it will be mildly bathed in radiation of some sort.
Space is mostly empty
So are the core of stars, “mostly empty” of matter isn’t specific enough to do calculations.
Sure, but we're talking insane amounts of time unless it hits something head one. Even the electronics are still alive and in 2024 after a long break we managed to get signals back. It is anybody's guess at this point how long the craft will remain functional but it will take a long, long time (long after humanity will either have destroyed itself or has figured out how to overtake it) before it is 'a melted lump of metal'.
Look at the metal that we routinely dig up in the hostile environment known as 'Earth' and which wasn't particularly designed to be long lasting. Voyager is just that: designed to last for a really long time. At a minimum several millennia, though of course by that time the electronics will no longer function, and not because they no longer have power but simply because they have degraded due to their rather more sensitive nature than the rest of the craft.
> I heard once it will eventually lose it's form entirely
It will be sitting at something like -450F. Could it really lose form!? Is the idea that all the phonons could converge to one point, shifting an atom of metal (which will happen infinitely with infinite time)? Maybe with random photons/hydrogen/whatever "continuously" adding energy?
Neat.
One issue is that over long enough timeframes, even atoms that we consider stable will decay - particularly ones that are heavier than iron, which will decay towards iron or nickel. That decay will eventually compromise the structure of the probes.
From what I recall, one of the hazards of long term space travel is that nearly any material will start sublimating atoms in the hard vacuum of space, with things like cosmic rays adding to the woes. Some over time it will start deteriorating.
Not sure about “melting” into an amorphous mass, I guess in theory the probes gravity could do that, but I would imagine even the tiniest force would disturb that and dissipate it.
It's cold out there, why would it melt?
It would ablate due to interstellar hydrogen, but that’s so rare over a billion years you’re taking a few millimetres.
It's got a very long time to do so. Like how a bowl of water evaporates at room temperature.
Heat ray from a passing flying saucer?
Radiation?
It'll come back on its own and want to talk to some whales.
No chance of it ever being hit by anything?
> It's expected never to encounter any other object in all eternity.
This is read as "near zero" rather than "no chance". "Expected" is a word of uncertainty.
I think the rough napkin math would be: take the volume that the probe will sweep through and multiply it by the volume of matter in the universe/volume of the universe.
So a virtual impossiblity? That's a finite improbability rather than an infinite improbability. I think I need a fresh cup of really hot tea.
Space is well named.
You think it’s a long way down to the shops, but that’s peanuts compared to space.
Ah, so this is how asteroids are made!
Despite all our rage we are still just rats in a solar system cage.
So radio communication would take longer than a day, that’s interesting.
My favorite conspiracy about aliens is that the nuclear explosion testing in the 50s had an observable effect and there’s some documented proof of maybe something was watching us: https://www.astronomy.com/science/did-aliens-watch-1950s-nuc...