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"The star is 2500 light years away from Earth."

Found that on google. Doesn't seem so far away :P



Yeah, unreachable without FTL travel.


It would take about 15.6 years [0] to reach the star on a ship capable of a constant 1G acceleration.

Here is the explanation and equations: http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.h...

[0]: https://news.ycombinator.com/item?id=6637131


15.6 years for the passenger, thousands of years from our perspective.


So after a few subjective years, you will be overtaken by newer and faster ships, and when you arrive, there will be a flourishing civilization already there to greet you.


And the people in the faster ships will be your grandchildren, yup. Plot of Heinlein's "Time for the Stars", pretty much.


I read this when I was younger and had no idea what it was called until now. I've tried to remember it a bunch. Thanks!


I was thinking of "Far Centaurus" by A. E. van Vogt, but I'll look up the Heinlein as well now.


Meh. People were willing to go half-way across the world to try living somewhere new, probably never to return. Announce the trip, and you'll have to weed out volunteers pretty viciously.


Does this take the needed deceleration in account? If we are to land there anyway :P


Yes, but the real problem is fuel( even with antimatter ). And radiation.


I agree that the real problem is fuel, but 10 years isn't quite long enough if you are going to accelerate halfway and decelerate halfway to arrive at low speed. For a 2,500 light year trip composed of two 1,250 light year legs, the time experienced by the ship will be (in units where c and a are both approximately 1):

2 * T(1250 lyr) = 2 * (c/a) arccosh (ad/c^2 + 1) = 2 * arccosh(1250 + 1) = 2 * 7.8 = 15.6 yr.


It is dubious we will ever travel faster than 10% the speed of light.

But a probe might be able to.


Not dubious - speculative:

https://news.ycombinator.com/item?id=4534359

https://news.ycombinator.com/item?id=6238297

Although, I certainly wouldn't bet against it long term.


If you did, you'd really be betting on your ability to collect / pay up the debt.


What does that even mean? Of course it is reachable without FTL travel. Besides time dilation which could make it a subjectively short trip, there is also cryogenics and other life extension techniques that could get us there.

If you accept any ship could get there, you might as well consider that space travel isn't the only technology that will advance.


> there is also cryogenics and other life extension techniques that could get us there.

You are aware those don't actually exist?

People assume they will exist, but we have nothing to base that assumption on except "it would be cool".


Besides the fact I think it's clear they will exist (assuming we don't destroy ourselves somehow), I already addressed that. We're already talking about things that don't currently exist. I can talk about a ship to Mars which doesn't currently exist. But both a Mars trip and cryogenics seem pretty reasonable to me.


> it's clear they will exist

???? Based on what exactly?

> But both a Mars trip and cryogenics seem pretty reasonable to me.

You think those are similar? We could do a Mars trip today with enough money. Every bit of money in the entire world would still not get you cryogenics - it requires a new idea that doesn't exist right now.


That is arguable, we have the freezing people but going. Sure it is being done in a very destructive way to the human body, it is a bet though that at some point in the distant future technology will get good enough that the current freezing method could be reversed.


There are animals that are naturally capable of freezing and thawing. We don't have to invent the process, we only need to adapt it. I bet it would be cheaper than a Mars trip.


We can't even freeze and thaw a steak and have it taste the same… let alone any living mammals.


just three years at warp 9 =)


It's strange to realize that even at Warp 9, it still take a very long time to get anywhere much.

In the TV shows and movies, they never seem to spend more than a few days at a time going anywhere at warp speed.


> In the TV shows and movies, they never seem to spend more than a few days at a time going anywhere at warp speed.

There are a few canon reasons for this:

1) Ignoring special episodes (and all of Star Trek Voyager) where they use a contrivance to hurl the ship tens of thousands of light-years, the working range of a starship on Star Trek is relatively small:

* The distance to the Romulan Neutral Zone, on the outer fringes of Federation Space, is only 28 light years away from Earth.

* Deep Space 9 (so named because it's on the outer frontiers of known space) is 70 light years away from Earth.

* Oo'nos, the Klingon homeworld, is ~100 light years away from Earth.

2) Ship speed exponentially increases as warp factor increases, and by the time the USS Enterprise-D is in service, warp 9 is fast, but not "I need to get there immediately because every plot shown on TV is an emergency" fast. The maximum sustainable speed for the Enteprise-D is warp 9.6, which is 1,909 times the speed of light. This would allow Picard to reach even Qo'nos from Earth in under 3 weeks.

3) With the exception of the JJ Abrams franchise (where they seem to keep going back to Earth after every mission), the ships featured in Star Trek are generally exploratory: between each episode, they'd roam their mission areas performing routine work. The episode plots would generally revolve around them dealing with an issue that happened to be close to wherever they happened to be at the time.

Of course, being a set of TV series and movies, liberties with distances were routinely taken. For example, in the first episode of Enterprise, they say Qo'nos is 4 days away from Earth at warp 4.5, which would place it less than half the distance between Earth and Alpha Centauri, the closest star system.


Most of the time they're moving at the speed of plot. It's a log scale I think so warp 9.9 is much faster than warp 9. Except whenever they remember the terrible idea they had part way into The Next Generation when they put a speed limit on space travel.


The TNG scale have a asymptote at Warp 10. The TNG scale come from a draw, and actually have a very complex formula derive from these hand draw graph, but can be approximated to a exponential scale below Warp 9.

TOS (and Enterprise) uses other scale with a much more simpler math exponential formula, were the same Warp factor is less quick that in TNG scale.

Actually the TNG scale is because Rodenbery like to give the impression that the ships are more fast that in TOS but he like to avoid using Warp 10 and huger numbers.

You can check it in http://en.memory-alpha.org/wiki/Warp_factor , appendices section.


Hell, in the new movies, you can transport from Earth to the Klingon homeworld instantly, and fly there in like 20 minutes.


Hell, in TOS they went to the edge of the galaxy (or back) in practically no time, under their own power.




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