In 1977 we launched Voyager 1. On November 18, 2026, it reaches one light-day from Earth, after 49 years of travel at about 61,000 km/h.
And it’s still nowhere.
Nearest star: Proxima Centauri, about 1,550 light-days away
Nearest big galaxy: Andromeda, about 2.5 million light-years away
Our fastest, farthest machine has barely left the driveway. We are a very long way from anything.
*My disclaimer: I calculated none of this. Everything here was gathered. Thought inspired by the article below. *
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Space is big, REALLY big
Even at that distance, the dust spheres of the Andromeda and The Milky Way are touching.
That’s gay ass hell
It’s not the fastest though, right? We had that parker space probe thingamabob do 10 times the speed of Voyager. Just need to figure out how to harness that, maintain comms, all that stuff it would pass Voyager in less than a decade.
We could make something that goes faster, but it would be tricky. Voyager got catapulted off of like 2 giant planets.
There were two Voyager probes. I believe Voyager 1 only got Jupiter, where 2 did all four gas giants
Get KSP streamers on it and it’ll be done in like a month, tops. Crazy bump in views awaiting whoever gets there first.
“Far out in the uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy lies a small unregarded yellow sun…”
We’ve got smartwatches now, though.
It’s all relative.
It’s been estimated, based on the background luminosity of the universe, that 50% of all the stars in the universe are not bound by galaxies. They drift between galaxies, each one isolated from its nearest neighbors by thousands of light years.
The night sky on a planet orbiting such a star would be basically black. The only points of light would be the other planets in their own solar system, there’d be no “fixed stars” visible to the naked eye. The nearest stars would likely be small M- or K-class stars, invisible at those ranges. If they happened to be somewhat close to a galaxy it might be faintly visible as a cloud or smudge in the night sky, like how Andromeda is visible. Human-like beings living there wouldn’t know other stars were a thing at all until telescopes were invented and wouldn’t know that those faint smudges were galaxies consisting of hundreds of billions of stars until modern telescopes were invented.
Those are the actual suburbs of the universe.
If you want to get to the boonies, though, the real wildernesses, you need to go to the Voids. These are the “bubbles” in the cosmic web, the regions of the universe that have almost no matter in them whatsoever. They’re so low-density that according to some theories the difference in gravitational potential has allowed time to pass more quickly there, so that out in the middle of a galactic supervoid the universe is about 18.7 billion years old rather than the 14.7 billion years it’s been down where we are in the thick of things. But despite their incredibly low density, there are still a handful of void galaxies out there. And if there are void galaxies, there are likely intergalactic stars that were ejected from those void galaxies as well. There wouldn’t be as many such ejection events though, since that’s mostly driven by intergalactic collisions, so the few void stars wouldn’t even have as many nearby neighbors as the intergalactic stars in our dense neck of the woods.
People who evolved orbiting one of those stars wouldn’t know that other galaxies existed until their equivalent of the 1960s - assuming they bothered with astronomy at all.
Early astronomy was largely focused on planets, and some still does today, so I imagine that urge would still be there.
By reading this comment I’ve learned something fun already today, thank you
assuming they bothered with astronomy at all.
It would probably come after the invention of radio. If you can send, and receive and there is a big void all around you, and you have learned that just because you can’t see something doesn’t mean it’s not there, you’d point a receiver somewhere random eventually.
It’s weird to think about a civilization discovering the stars after discovering the cosmic background radiation interfering with some of their most sensitive equipment.
They flew out of the cloud.
They saw the staggering jewels of the night in their infinite dust and their minds sang with fear.
For a while they flew on, motionless against the starry sweep of the Galaxy, itself motionless against the infinite sweep of the Universe. And then they turned round.
‘It’ll have to go,’ the men of Krikkit said as they headed back for home.
On the way back they sang a number of tuneful and reflective songs on the subjects of peace, justice, morality, culture, sport, family life and the obliteration of all other life forms.
Belgium.
I wonder if they’d be able to travel with ease. Stars were important for navigation premodern history yeah?
Sounds like it’s going farther from proxima centauri? I have no idea really just sounds like 1550 light days is further than 4 light years?
Nearest star: Sol. About 1 light day away.
Isn’t it like 8 light minutes away?
From us, yes. From Voyager, about 1 light-day.
Oh yeah, duh. My brain immediately thought they meant distance from Earth to the Sun, but they were talking about nearest star to Voyager. My bad.
Wait, if we could go near-light speed, we could make it to Proxima Centauri in “only” 5 years?!?
Yep. Problem is, you gotta slow down too. So the amount of time it took you to get to near-light speed would be the same as it takes to stop. Also, traveling at that speed means your whole family will be gone well before you get home.
Also, traveling at that speed means your whole family will be gone well before you get home.
Your family will be 5 years older (10 for the round trip).
You, on the other hand can be just days older, depending on the actual speed.
Also, traveling at that speed means your whole family will be gone well before you get home.
Would it work like that or would your family just see the 10 year round trip journey and to you it only took a few days?
99% sure that the round trip would feel like 10 years to you. After all, the distance is how long it takes light to get there. So, your family would experience a loooong time.
Wouldn’t it feel like 5 days at the speed of light? (Plus acceleration time?)
Yup…
Space is big.
Fabulous reference to scale. But I find the jump from proxima centauri to Andromeda a logical leap. Our species can very well reach other stars, it is increasingly within our technological capabilities. The closest stars are not THAT far away if we can consistently hit 50% the speed of light (solar sails are proposed examples). We will find an endless sea of reachable but barren planets and rocks and gasses and ice.
But in no conceivable reality will we leave the galaxy.
This post diminishes what is possible by scaling the argument up to what isnt.
Issue is more likely that as we discover we are deeply alone that all that travel isnt that worth it.
The closest stars are not THAT far away if we can consistently hit 50% the speed of light (solar sails are proposed examples).
Oh but they are!
First, even if we assume that speed is possible, the nearest stars are still practically unreachable for humans, and probes would take a lifetime to return useful information.
To use round numbers, let’s say a one-way trip takes 5 years at light speed and 10 years at 50% c.
That means a round trip would take 20 years at a steady 0.5c. But we don’t get to travel at a steady speed, we have to accelerate and decelerate. So the average speed should be roughly half the top speed. Now we have a 40 year round trip, or “only” 25 years to get signals back from a probe.
And second, our working assumption of consistently hitting 50% the speed of light is wildly optimistic. If we look beyond our spacecraft and satellites to the fastest objects ever created by humans, we are still working with well below 0.1% the speed of light.
If I wave a magic wand and make our speed capabilities 10x, which I think means increasing the power/fuel of our propulsion systems by 100x, we are still looking at well over 1000 years for a one-way probe trip.
The scale of our universe is bonkers, in both the big and the small.
Great exchange!
Did more digging:
Traveling at these relativistic speeds, laser-powered light sails could reach our nearest neighboring star (other than the Sun), Alpha Centauri, or the nearest known potentially habitable planet, Proxima Centauri b, in about 20 years. Both objects are a little more than four light-years away.
One day in the not-so-distant future, light sails may hurtle through space at speeds of around 20% of the speed of light (or 60,000 km/sec),
https://phys.org/news/2018-09-nanophotonic-relativistic.html
Considering how long humans opted to live on wooden ships and many lost their lives in pursuit of discovery, seems increasingly probable humans will be hurling some of ourselves towards these stars.
Even if we only find a bunch of barren planets, we can drop party favor bags full of various kinds of fungus, lichen, algae, yeast, bacteria, moss/fern spores, plant bulbs, rhizomes, nuts/seeds, succulent polyps, tardigrades, and diapausal insect eggs as we go.
Maybe special mixes for saltwater and freshwater environments in case we find any. Phytoplankton and zooplankton mostly, maybe some simple low-bioload crustaceans and other invertebrates like sponges, coral, hydroids, mollusks, and cnidarians. And some diapausal fish eggs like killifish.
Then come back in a few million years to see what grows.
The best time to start was a few million years ago. The second best time is now.
Shouldn’t be too hard to include well-balanced ecospheres in the interstellar arcologies that it would take to carry explorers to other systems anyway. Just isolate each species in a sterile enviroment before adding each one to the biospheres to minimize parasites and diseases, and then use science to determine the exact proportions to introduce them in to create a perfectly balanced ecosystem. And have a few quarantined backups in case something goes wrong with one.
Then they just have to keep a few sample pods on hand to drop whenever they find a suitable matrix for the biome starter-packs.
True! Science off for a second, science fiction on: I can’t help but see us as constantly projecting our own behaviors and insecurities onto the universe. I suspect we will be the seeders, and sci-fi is moving in that direction too the more empty space reveals itself as.
The hypothesis that we were seeded runs headfirst into the bottleneck of time.
The universe is 13.8 billion years old, while our Sun and Earth are 4.6 and 4.5 billion years old. Single-celled life emerged fast, roughly 3.8 billion years ago, almost as soon as the crust cooled. This suggests abiogenesis might be common.
Yet it took another 3 billion years just to cross the evolutionary Great Filter into complex, multicellular life, and nearly a billion more to reach intelligence. For an alien civilization to have seeded Earth 4 billion years ago, they would have needed to run that exact 4.5-billion-year marathon before our solar system even existed. That pushes their origin back to the chaotic, early universe, running into several major Fermi Paradox gates.
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at this time stars were almost entirely hydrogen and helium and advanced elements were rare.
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a far more dense universe made for far more cataclysmic impacts and intensity. We evolved the moment the universe’s density was sparse enough to create stability.
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mathematicians and cosmologists suggest if one planet was seeded 4 billion years ago its far more likely many more were. But thats not what our observations are revealing.
Math plus cosmological observations increasingly suggest we may become the seeders we prophesied.
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Building on this, we don’t even need to wait for some futuristic arcology to carry humans between star systems. We can send them on unmanned probes.
Step one is to create the ecospheres in orbit and stabilize them before loading them onto the probes. They’ll be sent off after maybe 10 years in space without manual intervention.
Step two is to build the probes. They should use solar sails to exit our system and get up to speed, ion thrusters for navigation/course adjustments, and some kind of nuclear power source like the Voyagers use.
Step three is to load the ecospheres into cluster pods on the interstellar probes.
Step four: send a probe off in the direction of each of the closest star systems. They should be programmed to do the following autonomously:
- As it approaches the target star system, it should either fold up or detach from its solar sail. This can be done with magnets for possible reattachment later
- It uses its thrusters to steer into the new solar system, and uses sensors to analyze each planet, moon, or major asteroid as it goes.
- It uses these analyses to program each cluster pod before launching one into the orbit of each suitable host
- The pod then orbits the planet or moon and uses the instructions it received from the main probe to identify target zones on the host.
- It then releases entry-capsules with its various ecospheres, targeted to zones suitable for the biome type (i.e. freshwater, saltwater, terrestrial; anaerobic and/or CO2/O2 -based respirating lifeforms; as well as temperature ranges (low extreme ≤ 0°C; medium = 0°C<t<100°C; high extreme ≥ 100°C; of course adjusted for atmospheric pressure and accounting for fluctuations due to latitude, rotation, axial tilt, and elliptic paths))
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- To avoid waste, a planet that only has an extreme temperature range can receive a special cluster pod loaded exclusively with suitable biospheres. Same for anaerobic hosts, etc.
- The entry capsules are of course designed to withstand the stresses of entry and impact, after which a timer starts. 5-10 minutes after landing, it opens and releases the ecospheres.
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- This can also happen in phases. The first release can be the lowest-bioload, most bottom-chain organisms; give them 20-30 minutes to disperse and then release the ecospheres that contain slightly larger/higher-chain organisms.
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- Additionally (or alternatively), the orbiting pods can release several capsules and give the groundwork organisms a day or two to disperse before sending more capsules with more complex organisms (in addition to more of the basic ones, of course)
And viola! The probe cruises through the whole star system, leaving a cluster pod orbiting each host. Perhaps they can continue tracking metrics with sensors and sending that information to the probe, and perhaps they could emit occasional signals so that if intelligent life ever comes by they’ll be able to find it. Or they could just become space junk and deorbit.
If the probe has more pods and there’s another star system nearby, it could re-dock in its sails and go that way. But this part isn’t as necessary.
But yeah send one or two of these to each nearby star system starting with the closest ones and expanding out gradually until we’ve sent at least one in every octant direction. Then do hexadecants, etc.
Some planet somewhere has to be a suitable host. I’m guessing more than one. If the pods identify active life they should have a killswitch so they don’t introduce organisms to any existing ecosystems.
But yeah, it’s how we got here originally. Some anaerobic microorganism riding on a space rock till it reached earth. Who knows where they originated, but those are our ancestors. So now it’s time to pay it forward, with interest…
I would argue that if we did get the capability to travel far and see more examples of other stellar systems, and then found time after time it was indeed totally barren and we were unusual… that would be VERY odd.
I’m old enough to remember before Pioneer and Voyager, and while scientists had hunches they’d learn more, the expectations of what we’d find for the gas giant and moons was a lot of the sameness. We instead found every one of them unique. Same rules of physics and chemistry, but combined in different ways so much that we still continue to learn more.
Look at Pluto. That single day when New Horizons passed by and gave us that data changed how we saw it (and I’m not talking about the planet status).
So back to being barren. We have no idea what a good sampling of planets could give us. We only have one example in the habitable zone here, and we’re still not sure we’re really alone yet. Mars, Europa, Enceladus, Titan. All still not well known, but getting learned about with each visit.
As for getting outside the system, I think it will take a breakthrough. Yes, there’s generational-type ships, but that’s one way and we’re having trouble getting off this rock. That’s more a question for those in a society who have already started exploring and living in this solar system, and that seems to be a ways off, if at all.
What is fascinating is cosmologists are rapidly flipping the odds from us finding other habitable planets and advanced life as being high to now being extremely low. Cool Worlds lab from Colombia University leads a lot of this research. The increasingly most probably answer to the fermi paradox is we are indeed rare, early, or even alone.
We can now peer to the edge of the universe and moments after the big bang, we have gone from cataloging our first non-solar system planet to over a million in a few years. And it all turns up barren. As professor David Kipping wrote recently, humans will either discover other life or never will, and the latter is perhaps more scary than the former.
I think it’s very possible we might be the first or one of the first examples of life in the whole universe. Life might not have been possible before third generation stars like the Sun. The mixture of metals/heavy elements needed for life is quite advanced. That said, i would also think that once life started somewhere in the universe, it would start popping up all over the place, so in another billion years we’ll find lots of examples. Also just possible we dont advance much further than this because we nuke each other back to the stone age or something.
Mathematicians and cosmologists are increasingly saying the same.
If I recall correctly, he’s talking about just advanced life. Habitable planets is its own category, and honestly tends to be squeezed into assumed parameters for what we know is possible, aka Earth. We’ve had those lines pushed before, when we found life in ocean trenches that we didn’t think would be “habitable”.
But his theory on the (small) window of time for life to evolve to advanced forms and intelligence for most stars was mind blowing to me. The only counter that works against it for all places is the number of chances it has to happen in different varieties in just this galaxy, not to mention the millions of others out there. We may never contact anyone else, but to think that with an average star’s life and a number of steps back we still got to where we are and yet it never happened anywhere else is very egocentric, almost as much as the old models where everything goes around the Earth.
Did it happen in this section of the galaxy? He may be right enough that no, it’s only a few in this galaxy, somewhere. And there’s the problem of distance again. So we might as well be along, without some new discovery to get past the speed of light.
Agreed. Professor Kipper talks about cosmic ooze being probable but the probability of advanced life keeps falling with every new model or discovery, is his point lately.
Right. The argument against abiogenesis (outside of the religious take) has always been how it’s too complex or the odds are against it, but there’s a good breakdown on the very old TalkOrigins archive taken from Usenet that shows from an odds pov, there’s not an astronomical amount of chemical combinations to make simple chemical replicators such a rare thing, indeed it’s a small number, and it’s more just having the conditions right long enough and enough tries. Well, we had that with early Earth. Once it cooled down enough, we had most of the planet’s surface running experiments over millions of years. Several different combinations were probably found and took off, and competition ended up with the few that were left. It’s certainly happened elsewhere too, there is nothing special about Earth outside of the parameters needed (which we’re not sure on which are absolutely needed).
I think recent research might even suggest that not only is it possible for life to begin with the right conditions, but that it’s almost a given something starts brewing the minute things get “right”.
Ooze may be everywhere, but leaps like towards multicellular complexity, seem to require an abundantly rare set of cosmic conditions that Earth seemed to give us by sheer, abundant luck. Plate tectonics lasting this long, a peculiarly stable G-type star, just enough meteorite impacts but not too much, stable temperatures that lasted billions of years. It took like 1.4 billion years to develop into complex forms. And from what we can see about the galaxy and universe, these conditions seem hard to find. We have a painful statistical case of one despite millions of planets now well within our gaze and measurement.
Like before, borrowing heavily from Cool Worlds Labs (Colombia University) calculations and peer reviewed models for my above reflections.
We really don’t have enough data to say anything about life on other planets. We’re pretty sure there isn’t any elsewhere in our solar system, but even the next closest one, proxima centauri, is too far away to tell for sure. We have barely any data about the condition of its planets.
We are growing increased confidence life is much likelier within our solar system
https://www.nasa.gov/news-release/nasa-says-mars-rover-discovered-potential-biosignature-last-year/
And theres a number of moons which are also suspected, but yet to be directly probed
We’re pretty sure there isn’t any elsewhere in our solar system
Are we, though? We have barely any data on gas giant moons, for example, and whether their subsurface liquid water oceans have any potential to support life. Europa Clipper is one mission supposed to reach Europa by 2030 and should hopefully be a good start to gathering this sort of data.
Agreed on the first. We’re finding out that there is a lot more planets out there than we ever thought, although in retrospect why wouldn’t there be? It’s now a question of their makeup and conditions, which we’re also starting to figure out slowly.
We’re very much not sure on our own system. A big part of one spacecraft already on the way, Europa Clipper, is to set the stage to look closer and see if we can answer those questions.
I think we have significant enough data to say quite a bit about life on other planets. It will have evolved, likely use a similar mechanism to DNA for heritable traits and be subject to natural selection. Use chemical processes for metabolism, utilise natural sources such as sunlight or underwater volcanic vents as part of it’s energy. Will likely have 2 sexes as that is the most efficient for genes and adaptibility. Will exist within specific zones with enough free energy to use ie not cold dark asteroids and not in places where radiation is so intense it disrupts chemical processes and destroys molecules.
unless there’s some shit we didn’t think of that makes some of that less certainly optimal.
Your fantastical overestimation of current real-world capability and simultaneous lack of imagination in the long term are a laughable combination.
I recommend subscribing to Colombia University’s Cool Worlds lab, which is where I got most of my points.
Edit: also
https://phys.org/news/2018-09-nanophotonic-relativistic.html
I can certainly conceive of ways that someone, someday, could leave the galaxy, its not like it breaks physical laws to do so, the trip just takes a stupidly long time and a ton of energy. But, any species that manages to leave its star system and continues to grow beyond it should have access to incredible amounts of energy and have a high tolerance for long term thinking, and with enough of those things, its theoretically possible to push something big enough to serve as its own self-sustaining world for a very long time, like an extremely large ship or even an entire solar system, to a high enough fraction of lightspeed as to give a decent chance of the thing getting to the targeted galaxy within the lifespan of the civilization inside, whose descendants now have, potentially, a galaxy or significant chunk of one to themselves if nobody else has arisen or traveled there first.
I agree but because of something you said. I hinted homo sapiens can reach other stars. But to reach other galaxies wed likely be another species by then.
What blows my mind is how it can still send signals after 49 years of tavelling and from such an astronomical distance and we are able to receive it and decode it.
It’s not that hard. Some isotopes have very long half-lives, and it doesn’t take much to power its equipment. Picking up the signal isn’t hard either, you just have to point a big enough antenna in the right spot and listen hard enough.
Voyager doesn’t even have to track Earth. It tracks the sun because it’s a much easier target. The spread on the transmission, especially at such great distances, means some of it will hit Earth.
The durability is pretty impressive too. Space is a harsh environment. A wayward micrometeorite or cosmic ray could hit the satellite and damage it or corrupt the software. Fortunately the folks at NASA are pretty good, and have been able to recover from a couple incidents of software problems.
“listen hard enough” thanks, I laughed.
You could say that. Or you could say we just think very small.
Space! It’s really, really big.
That’s a myth, it’s actually very small. If you collected all the space and put it in one place, it could fit in Rhode Island
I’ve read it’s mindboggling big.
It is slightly bigger than that.
And it’s getting bigger all the time. And that expansion is accelerating.
Only about 78000 more days!! Hang in there folks
Curious what you think of some of the ideas proposed in: https://youtu.be/MDM1COWJ2Hc
It’s fun to think about ways to iterate on what Voyager achieved, especially because we have upcoming opportunities that could easily go much much faster such as the Starshot
Actually we already know and are more like the galactic suburbs. It can be much more denser toward the center even assuming far enough to be technically survivable but then its way less dense on the edges.
Uh. Certainty? In my weirdly unexplained expanding Universe? No thanks.
The theories on how your cosmic “suburbs” operate do not guarantee we’re in one. The jury is still absolutely out on that one. We may be in the middle of nowhere levels of still under study, in fact: https://academic.oup.com/mnras/article/540/1/545/8129689?login=false
I think this depends how close you are looking and what your comparison is. The star density we are at vs star density in other parts of the galaxy is not something being argued along with our approximate position in a spiral arm. Its as certain as anything in science. I mean im talking the same way you would do for city, suburb, rural. density. in this case density of stars vs density of population.
