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What is a "light-year"?

Discussion in 'After Hours Lounge (Off Topic)' started by David Baranyi, Oct 2, 2003.

  1. David Baranyi

    David Baranyi Stunt Coordinator

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    While reading an article on the Sombrero Galaxy from hubblesite.org, I read that it is located 28 million light-years from Earth. I like to know: what is a light-year, and how fast would an unmanned satellite will have to travel to reach the nearest galaxy?
     
  2. John Thomas

    John Thomas Cinematographer

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    Not so much a measure of time as it is distance, it's the distance that light would travel in one year.

    "The distance over which light can travel in a year's time; --
    used as a unit in expressing stellar distances. It is more
    than 63,000 times as great as the distance from the earth to
    the sun."

    Specifically, it's 5.88 trillion miles or 9.46 trillion kilometers.
     
  3. Ted Lee

    Ted Lee Lead Actor

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    i've always thought the concept of light years pretty cool. kinda neat to think that the light you see from some stars could have been travelling for years and years before it got to you.
     
  4. David Williams

    David Williams Cinematographer

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    and don't forget we're talking about light speed as expressed as the speed of light in a vacuum.
     
  5. John Watson

    John Watson Screenwriter

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    about 365 times longer than a light day [​IMG]

    Oh, I gettit! A question for science guys. Sorry!!!
     
  6. Kirk Gunn

    Kirk Gunn Screenwriter

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    Isn't a nanosecond the time it takes light to travel a foot ? or is it a metre ?

    And here's one for the scientists...

    Can someone explain, in an "Einstien for Dummies" format, the whole reason you can't travel faster than light speed ? Thanks
     
  7. Justin Ward

    Justin Ward Supporting Actor

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  8. CharlesD

    CharlesD Screenwriter

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    To answer the second part of the question, the nearest galaxy to our own is Andromeda which is 2.2 million light years away. It took the Voyager probes more than 25 years just to reach the outer edges of our solar system.

    If it took Voyager 25 years to cover 80 AU, then it would take 19,687.5 years for it cover one light year (63,000 AU = 1 light year). Andromeda is 2.2 million light years away so (if it was heading in the right direction) one of the Voyagers would get there in
    43,312,500,000 years!
     
  9. Mike Wladyka

    Mike Wladyka Supporting Actor

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    1 parsec equals 3.2616431 lightyears, makes me wonder what is the kessel run is? obviously a distance in which some speed needs to be reached?
     
  10. MarkHastings

    MarkHastings Executive Producer

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  11. AllanN

    AllanN Supporting Actor

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  12. Leila Dougan

    Leila Dougan Screenwriter

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    "To infinity and beyond!"

    Sorry Mark, just had to [​IMG]
     
  13. Mike Wladyka

    Mike Wladyka Supporting Actor

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  14. Kevin P

    Kevin P Screenwriter

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    I've heard it's possible to go past the speed of light, but you can't go AT the speed of light. So if you can jump to faster than light without accelerating to light speed, you're all set. Heck maybe I was reading about Star Trek warp drive or something. [​IMG]

    Anyway, someone asked about the Kessel run. I think Han Solo was bluffing. A parsec is a unit of distance, not a unit of time like he used in that sentence. Of course, maybe in that galaxy far far away the term "parsec" is a unit of time rather than distance. [​IMG]
     
  15. MarkHastings

    MarkHastings Executive Producer

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  16. Jeff Gatie

    Jeff Gatie Lead Actor

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  17. Jack Briggs

    Jack Briggs Executive Producer

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    The Megallanic Clouds, companion satellite galaxies to this one, are much closer.

    No "time" is involved in a light-year; a light-year is a measure of distance (as noted, the distance light will travel in a year in a vacuum). And, according to what is presently known in physics, the speed of light is the absolute speed limit in the universe.

    Which is why so much of what Hollywood passes off as "science fiction" is so laughable. People, especially Hollywood directors, producers, and writers, are largely incapable of imagining what a staggering distance a single light year is. There would never be any hopping from the "Neutral Zone" to "Federation territory" in a mere matter of minutes.
     
  18. Patrick Sun

    Patrick Sun Moderator
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    Isn't a Light Year just a year, but with less carbs?
     
  19. CharlesD

    CharlesD Screenwriter

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    Yeah I know about the Clouds of Magellan but don't really count them as separate galaxies as they are satellites of our own galaxy. As an aside they are spectacular to see, on a dark night they really do look glowing clouds.
     
  20. MarkHastings

    MarkHastings Executive Producer

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