It already is and so is time travel but you wouldn't believe someone on the internet?
this post was submitted on 05 Feb 2026
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Not for humanity, not as we currently understand ourselves as humans anyway.
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.
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 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. Never.
No.
Especially with the kind of people who're in charge of handling space travel. You know who.
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
Why do you say wormholes are impossible? We don't need a reason to believe it, because what we do or don't believe doesn't change whether or not something is possible.
Humans didn't have a reason to believe in electricity until they did. Humans didn't have a reason to believe in computers until they did. Humans didn't have a reason to believe in gravity, nuclear energy, relativity, or quantum mechanics until they did. Same deal for germs, internet, cell phones, the list goes on.
Point is, until someone solves Unified Field Theory and unless it definitively proves that wormholes, alternate dimensions, and parallel universes are fundamentally impossible, we can't claim to know what isn't possible a hundred or a thousand years from now.
We might not have a particular reason to believe, but we don't have any reason to disbelieve, either.
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.
Isn't Venus's atmosphere dense? If so, you could just float a Bespin-like Cloud City on a convenient layer of the atmosphere to avoid the boiling temperatures below and the crushing weight of the air...
You could, or you can add water and cyanobactera. Venus's atmosphere is pretty close to what ours was minus the water and cyanobactera when the planet mostly coole d off after the collision with Theia.
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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.
Yes.
Totally.
The Milky Way is on a collision course with Andromeda, so we are already on our way!
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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
Me fail english!? That's unpossible!
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.
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.
We could reach any point in the visible universe in 2 years.
Jesse, what the fuck are you talking about?
The observable universe is a spherical region of the universe consisting of all matter that can be observed from Earth; The radius of this region is about 14.26 gigaparsecs (46.5 billion light-years or 4.40×1026 m).
Traveling at the speed of light from earth to the edge of the visible Universe, would take around 23 billion years.
Technically the visible universe extends only about 13 billion light years from us. We can just calculate where that stuff is now because of expansion. And as I wrote the area we're aiming for will surely change drastically the further away it is.
These journeys wouldn't take billions of years for someone traveling near light speed because for them the lengths would shrink down so much that they'd be negligible. Of course once they had slowed down those billions of years will have gone by for everything outside the space ship. So it's not good for missions where you want to return home to your family afterwards.
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 hope everyone holding power now will be long dead and forgotten before humanity reaches that level of diaspora
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.
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