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If we could travel near the speed of light

  1. Feb 14, 2009 #1
    ...where would you go?

    If a new technology allowed a spacecraft to travel at say 0.5c, and life on board this ship could be sustained indefinitely. If this ship was built tomorrow, where do you reckon it would go? Andromeda? pluto? centre of milky way? alpha centauri?

    Just though it would be fun to see thoughts on what you guys believed would be the most promising destination.
     
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  3. Feb 14, 2009 #2
    Alpha Centauri or Pluto would be the most feasible
    Centre of Milky Way inadvisable owing to the black hole that I believe is lurking there and although I don't know where Earth sits in relation to the centre, it's probably a long way even at 0.5c.
    In the case of Andromeda (I'm no astronomer) but isn't that seriously millions of light years away? It wouldn't be a case of where would you go so much as where would the ship go, no-one starting the journey would live to get anywhere near the destination, let alone the return leg; it would need to be a generational ship which likely would still be doomed to failure through obsolescence. Imagine one or two generations into the journey, technology back on Earth has pulled up and you find yourself being overtaken with contemptible ease by a ship that left 20 to 40 years after you.
    If you're suggesting we're all in stasis then we just won't see ourselves being overtaken, unless they're polite enough to come aboard, wake us up and take us with them.

    While we're stuck with 0.5c technology, I'd do the local rounds
     
  4. Feb 15, 2009 #3

    Chronos

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    Traveling at the speed of light is impossible.
     
  5. Feb 15, 2009 #4

    HallsofIvy

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    What was your point in writing this? No one said anything about traveling at the speed of light.
     
  6. Feb 15, 2009 #5
    Yes Proxima and Alpha Centuria would probably be quite good candidates considering the possibility of a planet in the system due to a slight stellar wobble.

    Perhaps some of the closer stars that exhibit possible planets would be interesting to visit. A lot of these stars are 'so to say' in our back yard.
    Two interesting ones being 18 Scorpii and Gliese 581.

    Andromeda, would be out of the question at 2.5 million light-years unless traveling very close to the speed of light.
    I think time dilation would have to really kick in here.

    However, on the bright side the Andromeda Galaxy is 'headed' in our direction and will eventually collide with our galaxy.
    So, if we wait long enough the trip will be substantially shorter.
     
  7. Feb 15, 2009 #6
    Yeah I think you guys are right. Going to the nearest galaxy is simply too far away. I can't imagine people wanting to begin a voyage to a destination that was millions of years away. In fact, there is probably a better chance of waiting for wormholes!
     
  8. Feb 16, 2009 #7
    I can't help but suggest if we had a single ship capable of 0.5c we could use it to launch lots of probes (just go top speed in a certain direction and release them). Although I guess this isn't really keeping with the spirit of the question. Next I have think we could just use it as a ferry, and set up orbiting stations around all the planets and major satellites in our solar system, which would allow parallel study of most of the solar system at once.

    However, if I limit myself to only being able to visit and study any one place at any time I'd have to say we use it for the solar system first, spending about a year here, then move on to the near stars. While visiting a completely new star would certainly be amazing I can't overlook how insanely quickly we could get around our solar system, most of which we really haven't studied up close at all (mainly the outer planets satellites). Although I suppose acceleration would greatly limit the ability to make short trips. But hey, this is fantasy anyway right?

    As for if people would be willing to visit very far away places (other galaxies), I think they would. I don't think it should ever be that high a priority. But if building a large ship capable of near c speeds becomes possible for relatively cheap (and I think it will, in a few hundred years), then I don't see any reason why not. Sure the people leaving would never see the other galaxy, but they won't see it sitting here either. Their chances aren't that great, but if we never come up with some way to cheat the speed limit of light (worm holes, warp drive), which is a very likely possibility, then it means once we are capable of even 0.5c we might as well start making these long journeys. It's unlikely that we'll be gaining much more. I suppose you could argue that we should wait until we can reach a high enough speed to make the journey in a single lifetime (due to the slower passage of time for the people on board). Sure millions of years would have passed here, and millions more before any news could be transmitted back, but at least the people who set out could actually be alive for the arrival. That would also help with the problem of a generation ship losing all memory of the culture that sent it, as well as the very real problem of how to keep a ship running for millions of years.
     
  9. Feb 16, 2009 #8

    Chronos

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    My error. I misread the op.
     
  10. Feb 16, 2009 #9
    Well if it was just me in it, and can only go 0.5c, I'd set the ship on a course to get a long series of gravitational boosts from stars in our galaxy. Keep doing that for awhile until I get super close to c, where hundreds of millions of years are passing out in the universe relative to me inside the ship. Cruise around like that and periodically wake up to watch the evolution of the universe on the largest scales through to the end of time. Maybe? I may need some special Doppler-effect compensating windows.
     
  11. Feb 17, 2009 #10
    it technacally is, but we could use wormholes. And i would use the device to get to the heliopause (i think its called that) of the sun.
     
  12. Feb 18, 2009 #11

    Chronos

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    Travelling near the speed of light is difficult. The energy required is enormous, and the results are not good. Light in the direction of travel is extremely blue shifted [you fry].
     
  13. Feb 18, 2009 #12

    Vanadium 50

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    At 0.5c the blue shift is not that big. Of course, the down side is that it takes a long time to get anywhere.

    As far as stellar gravitational assists, you would need thousands of them to get to anything like a substantial fraction of c. And thousands more to slow down when you got to where you were going. It's far from clear you wouldn't be better off just flying to where you wanted to go.

    Finally, there is no evidence that there are wormholes.
     
  14. Mar 31, 2009 #13
    Considering that space is a vacuum, all you need is a little push and a lot of time, and your speed would increase. You wouldn't need to slingshot yourself on other stars gravitational field. But the problem comes that at a certain speed molecules start to separate. So in theory, you, and your ship would disintegrate. *sigh*… that is why scientists are trying to develop a “plasma” shield.
     
  15. Mar 31, 2009 #14

    Vanadium 50

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    This is not true.

    I don't think this is true either. Which scientists?
     
  16. Mar 31, 2009 #15

    DaveC426913

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    I think is is not possible even in principle. There's got to be an upper limit on how much of a boost you can get.

    I think anyway...

    If you were approaching Jupiter at .1c could you still get any boost from it?
     
  17. Mar 31, 2009 #16
    It seems like you don't understand the basic principles of relativity, at a certain temperature they start to separate but it have nothing to do with uniform speed.
     
  18. Mar 31, 2009 #17

    DaveC426913

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    What are you talking about? Relativistic speeds cause molecules to separate? No. Or are you simply referring to high temps causing materials to vapourize? Yes.
     
    Last edited: Mar 31, 2009
  19. Mar 31, 2009 #18
    At the speed of light, your mass is converted into energy.


    I honestly don't know. I read it in a magazine somewhere. They were trying to make plasma cold enough to not damage a vessel, but yet extremely hot on the outside. Thus - > "Shield". It could be bs, or not. But it was pretty convincing.

    ie.jpg
     
  20. Mar 31, 2009 #19

    DaveC426913

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    No it isn't.

    Your mass will not reach the speed of light. Ever.
     
  21. Mar 31, 2009 #20
    If it did, in theoretical terms, that is what would happen.
    never say never. ; )
     
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