Not for humanity, not as we currently understand ourselves as humans anyway.
this post was submitted on 05 Feb 2026
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Yes.
I can picture the possibility of a probe visiting our nearest neighbors
But there are so many problems with a generation ship going that far, and no, none of the fun sci fi ways of travel are possible.
Bringing this back to reality, I can definitely see exploring more of the solar system and I can see making use of resources on hand for bulk consumables like fuel, oxygen, water, housing (we’ll have to to make it work). But consider how many things it would take to actually be independent of earth and how large the colony needs to be. Remote bases in our inner solar system can get away with that, but you can’t leave the solar system and expect to rely on any resupplies from earth.
Even if you could achieve the travel time to visit another star system and build a generation ship with enough supplies of everything and that could function that long, how would you survive without a preexisting functional colony of millions of people? Just start with the thousands of types of plastics we use every day and imagine trying to support that for a few people, without oil to drill or other organic chemicals to mine, and without a full scale chemical industry
No, I genuinely don't believe it will. I don't think the human race will ever reach another star, though I do believe it could be possible if we avoided going extinct for a few thousand years.
Another galaxy? No chance, not unless we figure out FTL, which I don't believe is likely. The only FTL I've heard of that might be possible is the Alcubierre drive, but it relies on things that are so exotic, it's likely impossible to create one.
With our current understanding of physics it is impossible. Sucks, I love sci fi but they all rely on inventing some magic machine to make it possible.
And to be clear, when you occasionally read about someone saying it’s not impossible……. That’s late night bs sessions on illicit substances. Usually the article is really “from our understanding of physics we have this math equation where we can actually enter values and the equation still gives a result, given a list of impossible prerequisites.
No. Never.
Speed of light limitation. Andromeda is 2.5 million light years away. Even if someone debunks special relativity and finds you could go faster than light, you would be moving so fast relative to cosmic dust particles that it would destroy the ship. So, either way, you cannot practically go faster than the speed of light.
The only way we could have intergalactic travel is a one-way trip that humanity here on earth would be long gone by the time it reached its destination so we could never know if it succeeded or not.
We will just have to let Andromeda come to us.
I hope everyone holding power now will be long dead and forgotten before humanity reaches that level of diaspora
No.
Especially with the kind of people who're in charge of handling space travel. You know who.
Technically yes, but also no.
At least not casually; flying between star systems at will, faster than light between star systems, etc...
I'm sure at some point, if scientists confirm the habitibility of a world orbiting a star relatively nearby, some group or other would probably get a Generation Ship concept going and head out. Musk or some other fucking billionaire looking for a world to conquer. So technically that is interstellar travel, but not really as it's just a one way point to point, not a taxi service.
Interstellar != Intergalactic
No, but yes- of course assuming humanity continues in a meaningful way. I mean technically we are already travelers- we're already traveling through space at high speed.. https://cosmic-odometer.vercel.app/
In terms of lightspeed travel, I think no, and definitely not sci-fi warp tech, BUT generational ships where people live and continue to reproduce over gigantic time scales could. If a ship had enough space, ecosystem of its own, etc- we could continue at "sub light" travel pretty much indefinitely without any ludicrous scientific advances beyond radiation shielding, etc.
Again though, that's a long, LONG way off and would require we stop trying so hard to off ourselves and the lovely little blue marble we currently traverse life on.
Has anybody here heard about the Alcubierre drive?
It's SWEET, but still relies on exotic matter that may not exist in our physical reality
Greg Egan's Diaspora sets out how humanity could explore the galaxy and even the multiverse, which if you can't be bothered reading consists of:
- Upload conciousness into computers, leave physical bodies.
- Miniaturise computers until we have spaceships in the grams/nano grams
- As we're no longer connected to time we can build massive solar system sized technologies, built by nanotech, that sure could take hundreds of years to build but in our virtual realms we could easily sleep.
- Use Lasers to propel our nanogram spaceships to 90% light speed. Even then for the astronauts, time is almost nothing (time goes slower the faster you go). A trip across the galaxy would feel like mere weeks to you. We could explore the universe as immortals.
- At this point we should have a pretty good understanding of dark matter/energy and how to move between universes (the multiverse, depending if you accept it as a base for explaining non locality)
- Which would allow us become eternal.
In the here and now the only way to travel to another system with our current tech is via nuclear pulse engines.
Basically you build a large spaceship. Stick it on massive shock absorbers which are in turn connected to a metre plus thick steel plate.
Cut small hole in the middle. Have a door that opens closes.
Eject 1kt explosive device out door. Repeat 500x till you get to orbit.
Basically you could get a spaceship up to very high speed with nuclear pulse engines to turn a multi hundred year journey into less then 100 years.
That said the biggest problem with interstellar journeys is that our material science and manufacturing tolerances are pretty shit. Essentially all of the air will leak out through the metal skin of the spaceship.
I still think carving put an asteroid, sticking engine on it (see nuclear pulse engines) , covering it in ice and water will solve the problems radiation shielding, losing critical gases and provide ample fuel and water for a very long journey.
I know enough physics to say no Even inter-Stellar is out of our reach (without generation ship).
We have zero reason to believe in an effective way to build wormhole, jump gates or anything similar. Even high energy cosmic rays have a limited range (due to collision with photons) which is a strong clue that there is no shortcut in space
Strap a solar thruster to the sun, and the Earth and Venus can be used as generational ships. The rest of the solar system will follow the sun. The starlifting array needed to power the thruster will keep the sun "young." There's more than enough Hydrogen and Helium to dump in as fuel.
Venus is a fixer upper, but it just needs several oceans worth of water ice, and some cyanobactera flung at it to cool it down. Maybe we can look into diverting some comets into Venus, I dunno.
Fuck it, let's assume we can build jump gates.
Let's say they're just big enough to send a tiny unmanned drone through.
I hop into my space ship and accelerate with a conventional engine to 86% of light speed.
No violation of physics needed, just shitloads of energy.
I fly to another star, which takes 10 years from earth's point of view.
Due to time dilation at 86% light speed, time in my space ship passes half as fast as on earth.
If someone on earth had a strong enough telescope, they could look at a clock on my ship and see that it ticks half as fast as the clocks on earth.
But in my frame of reference, earth moves away from me at 86% light speed.
So if I look at earth through a telescope, I see that the clocks on earth tick half as fast as mine.
There isn't a universal time. Time is always relative to speed and this is no problem when the reference frames are separated.
I arrive at the star, after 5 years have passed on earth.
I activate a jump gate and send the drone through with a message. It arrives on earth instantly, 5 years after I left.
But from their reference frame, they could see my clock ticking only half as fast as theirs.
After earth's 5 years, only 2.5 years have passed for the space ship they see.
They activate their jump gate and send the drone back with a reply.
It arrives instantly at the star, 7.5 years before my space ship gets there.
This is why FTL travel isn't and will never be possible. Even with tricks like jump gates or wormholes, it creates time paradoxes.
That's not how it works. You're correct when you say that from your point of view it's Earth's clock going half speed and from Earth's point of view it's your clock going half speed while you're traveling away from Earth (or Earth is traveling away from you, both are equally valid), but that's only true as long as the distance between you and Earth continues to increase at 86% of the speed of light. As you decelerate at your destination your reference frame continuously changes until you're back in the same frame as Earth (or nearly so, we can assume the two stars aren't exactly maintaining their relative positions). While you're decelerating, from your perspective Earth's clock speeds up and goes faster than yours, how much is determined by your rate of change in relative velocity. Earth's reference frame isn't changing (ignoring movement around the sun, galactic center, the great attractor, etc.), so the Earth's perspective on your clock doesn't change, the Earth sees your clock gradually speed up as you "slow down" until it's going the same rate, but never faster. So once you're back in the Earth's reference frame both you and the Earth will agree that your clock advanced 5 years while Earth's clock (and your destination's clock, adjusted for any relative movement between it and Earth) advanced 10 years. This assumes a constant 86% light speed and ignores the time accelerating at departure and arrival so let's assume very fast acceleration so it doesn't change more than a couple days.
Edit: this is all completely ignoring gravity based time dilation from the spaceship climbing out of Sol's well and going down the destination's well and only considers velocity based time dilation. It would be more correct if you only considered two spaceships in a void where one accelerates to relativistic speeds and then accelerates back into the reference frame of the other.
Assuming a mechanism exists that changes the universe from being singly connected to multiply connected (i.e., wormholes exist), it is possible to have wormholes permitting faster-than-light travel without time paradoxes, though some additional restrictions may apply.
We have already shown that wormholes connect across both space and time, so that a trip between star systems could take you hundreds of years into the future, and the return trip takes you hundreds of years back in time. And this is even before we throw in how time slips between planets when considering relativistic time dilation due to different speeds and gravitational potentials.
Fortunately, all the weirdness of different time rates and going backward and forward in time can be ignored by the average person. This is because you never need to go from one world to another, or back, across the vast gulfs of interstellar space. You just take the wormhole between them. All you ever need to worry about is the coordinate frame that goes across the wormhole. When considering this reference frame, you're not hopping all over the place in time. If it takes ten minutes to cross the wormhole between the two planets, when you get to your destination world the clocks will read ten minutes later than they did when you left your departure world. By coordinating their time-keeping across the wormhole network, all of the worlds of the network can agree on a common time to coordinate their activities. This is all travelers ever need to worry about, and they can then ignore all the relativistic weirdness. Your network engineers will still need to keep track of relative time drift and how close a given configuration is getting to a time loop. But unless your protagonist is a network engineer, they can just ignore all that stuff. And, as an author, so can you! Assume your engineers are competent, you have good regulatory bodies and standards institutions, and don't worry about any of this "time travel" that doesn't actually let you cause paradoxes.
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Totally.
The Milky Way is on a collision course with Andromeda, so we are already on our way!
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The big problem is energy. If we had almost infinite energy we could accelerate to a significant fraction of the speed of light at a leasurely 9.81 m/s² in about a year. The travel at almost lightspeed would feel instantaneous for us. Add another year to decelerate at the same rate. We could reach any point in the visible universe in 2 years.
Our destination would just be drastically different from what we observed, depending on how far away it was.
Oh, and apart from the tiny energy problem cosmic radiation will probably destroy our spaceship. I bet at relativistic speeds you'd even get enough neutrino collisions to make them a problem.
There is another layer. You are not only trying to travel through space, but also time.
We know the formula: s^2 = (ct)^2 - d^2
s: spacetime distance/interval (invariant no matter the observer)
c: speed of light
t: time
d: coordinate in 3D space
Now, let’s say we have 2 travelers who need to meet at a certain place. Traveler A is 1 spacetime distance unit away Traveler B is 2 spacetime distance units away.
If they are both at the same age when they started the journey, B would be younger than A even though A is closer to the destination than B! Because B experienced more time dilation, and A needs to either wait at the destination, or travel slower.
So to meet each other at a relatively same age, B needs to travel slower on purpose, or A can take a detour.
Millions of years become meaningless, people who have no spaceships would be a death sentence. They would never see loved ones again. So in a sense, enormous ships that can travel at near the speed of light are a norm for that type of civilization.
We are unfortunately at a very early time of the universe. If we are born later, we could probably see other civilizations travel to us :D
Space travel is weird. Brain hurty.
I think it is more a question of will we make it that far. If so then it should be possible but I don't expect it would be the norm and likely single way. Communication back home would be almost pointless due to the distance.
Perhaps it will be like the Rimworld lore. FTL is never achieved, civilisations are unable to remain stable once communication takes more than a few years or decades between planets as culture drifts over time. This doesn't prevent intergalactic travel but it does make it a one way colonisation mission.
With a generational ship and a shield and a way of blocking cosmic rays I think it will eventually be possible, but take a very long time. I don't believe light speed will ever be possible, but going near light speed starts slowing down time a whole bunch for those on board the ships. So if for instance we came up with some trickery to get up to 99% the speed of light and wanted to go to a planet one galaxy over that's 25,000 light years away, in theory the ship and the people in it would get there in about 1200 years. Even though it would be like 25,000 years for anyone who wasn't on the ship. At 99.999% it would only take what would seem like about 115 years on the ship.
I'm not going to say that's flat out impossible that it could happen but we'd have to find one hell of a way to cheat the system.
Alternatively, I think it will come about (if humans don't kill ourselves off) that a person can "live forever" in one form or another. If we get to that point then pesky things like travel time and atmospheres and such will be much less an issue. I then wonder how long a person would want to be around before they decided they'd rather "self terminate".
Humans? Nope. Some kind of actual AGI that doesn’t care about long time scales and can be lashed to a metal rich asteroid and flung out of the solar system? Still probably not, but it could maybe make it to some interesting intra-galactic destinations.
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I suppose it all hinges on what humanity manages to figure out, physics-wise. I like to keep the door open
Probably not. Main problem is energy density.
Theoretically we could visit things thousands/millions of light years away within a human lifespan, but the necessary energy to do so is just infeasible. You'd have to spend half the energy slowing down at your destination so you'd need all that energy onboard. Just not happening IMO. As a bonus you'd basically also be inventing a time machine (forward only)
Interstellar travel? Like to the nearest star systems? Maybe. In the far future. But not intergalactic. Andromeda is the closest galaxy and it's 2.5 MILLION light years away....
No, not unless we have made some serious mistakes in our understanding of physics.
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Nope
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