Page 2 of 2 FirstFirst 12
Results 31 to 45 of 45

Thread: STTNG Bad Astronomy?

  1. #31
    Join Date
    Oct 2001
    Posts
    270
    Love the concept, can't ever imagine it occurring. I did some web research on them as well, and basically, one could never really be built.

    There simply is not enough material in our entire solar system to construct a full sphere around our sun. (Or probably any other sun.)

    If a civilization could import the material, sure it could be built, but if you could go to another solar system to get the material, heck, why not just take up residence there.

    There are some calculations which suggest that there could NEVER be enough matter in a single solar system to construct the sphere. If there was, then it would have evolved already into a binary system, or some other contrivance.

    I suppose there are tons of theoretical solutions (nebula vacuuming comes to mind) but none really seem practical, no matter what the technological capability.

    DJ

  2. #32
    Join Date
    Jan 2002
    Posts
    130
    You could always use <h3>REALY</h3> Big replicators [img]/phpBB/images/smiles/icon_smile.gif[/img]

    Darasen

    <font size=-1>[ This Message was edited by: Darasen on 2002-02-22 16:42 ]</font>

  3. #33
    Join Date
    Oct 2001
    Posts
    270
    Ayup, that would do it. Really really big. However, would it then be my understanding that replicator technology makes something from nothing?

    If in fact they make something from something, then one would need an equal mass of some thing, whatever replicators eat I guess... so bzzzzzzzzt. [img]/phpBB/images/smiles/icon_wink.gif[/img]

  4. #34
    Join Date
    Oct 2001
    Posts
    2,677
    I remember reading somewhere about building a Dyson Sphere with some kind of energy-matter converter. Just set up a field of some sort around the star and use it's own radiating energy to create a shell of super-strong matter around it. Just a simple 2-step process. [img]/phpBB/images/smiles/icon_lol.gif[/img]

    As for "Relics", I remember one thing that bugged me about it. When the Enterprise was inside the sphere, the inner surface was covered with various highly visible terrain and water features. But of course, at that scale such features would have to be absolutely gigantic to be visible at all--I mean world-sized and bigger. There should have been no more than a vague blue-green haze all around them.

    But then again, that wouldn't make for very good TV would it?

  5. #35
    Join Date
    Jan 2002
    Location
    The Valley of the Sun
    Posts
    9,561
    According to my calculations, if you convert the volume of the earth to a Dyson Sphere of 93 million miles radius it would be about .38cm thick. There's a lot more matter in the solar system than that. How thick would it have to be?

    The most horrible thing about Relics is, when Scotty finds out his rescuers are from The Enterprise he says he wouldn't be surprised if Jim Kirk himself brought the ship out of mothballs to come looking for him. But in Star Trek: Generations, which takes place decades earlier, Scotty is aboard The Enterprise-B when Kirk is apparently killed by a hull breach. He should think that Kirk is dead.

  6. #36
    Join Date
    Oct 2001
    Posts
    6,275
    Hmmm...

    At m = e/c^2, you'd have to trap a whole lot of energy to make each gram of matter. Even at 100% efficiency, you couldn't accumulate mass faster than the star was burning it.

    In its nuclear fusion processes, our sun loses about 5 million tons of mass per second. If it's one AU in radius, our Dyson sphere has a surface area of about 1.1x10^17 square miles. Assuming we can turn all that radiation back into mass, we'll get about one millionth of an ounce per square mile of our sphere's surface per second, or about three pounds of matter per square mile per year. And of course, this is a very optimistic scenario; any real conversion process would be considerably less than 100% efficient, even if it could trap the entire flux of the star.

    We're gonna have to wait a long time before we call for the moving van...

    (Sorry about the funky units, I didn't feel like converting everything to SI.)

    ...

    Could that episode of ST-TNG have been made, or at least written, before the Generations script? Maybe it was the latter that was "wrong". Of course, there are numerous other ST non-sequiturs and contradictions. For example, we should have already had the "genetic wars" that led to Khan fleeing Earth.

    ...

    By the way, Larry Niven has written some very entertaining speculations about ringworlds, Dyson spheres, and similar schemes. My favorite is the "spaghettiworld" concept: a relatively small tube (in cross section) stretching around the star, with windows to let in the light, rotating around its long axis for gravity. It's easy to build up from relatively small sections to much longer ones, and they can be extended all the way back to form a closed loop... or simply extended indefintely, looping around and around the star until you have a tangle of inhabited spaghetti.

  7. #37
    Join Date
    Oct 2001
    Posts
    7,732
    I am fairly familiar with the works of Larry Niven , but I cannot recall reading about "spaghetti world". Could you point me to a book or story where he discusses it?

  8. #38
    Join Date
    Oct 2001
    Posts
    6,275
    Niven's discussion on ringworlds and the like can be found in his collection A Hole In Space, in the essay titled "Bigger Than Worlds".

  9. #39
    Join Date
    Oct 2001
    Posts
    164
    On 2002-02-23 20:24, Donnie B. wrote:

    Could that episode of ST-TNG have been made, or at least written, before the Generations script?
    Relics aired as the fourth episode of the sixth season. Generations was released six months after the series finale. IIRC, the filming started right after the end of filming on All Good Things... IMO, they just didn't do their research. Also, IIRC, it was said that he had degraded some while in the transporter buffer for 75 years.

  10. #40
    Join Date
    Oct 2001
    Posts
    2,677
    On 2002-02-23 20:24, Donnie B. wrote:
    Hmmm...

    At m = e/c^2, you'd have to trap a whole lot of energy to make each gram of matter. Even at 100% efficiency, you couldn't accumulate mass faster than the star was burning it.

    In its nuclear fusion processes, our sun loses about 5 million tons of mass per second. If it's one AU in radius, our Dyson sphere has a surface area of about 1.1x10^17 square miles. Assuming we can turn all that radiation back into mass, we'll get about one millionth of an ounce per square mile of our sphere's surface per second, or about three pounds of matter per square mile per year. And of course, this is a very optimistic scenario; any real conversion process would be considerably less than 100% efficient, even if it could trap the entire flux of the star.

    We're gonna have to wait a long time before we call for the moving van...
    Well, leave it to the brains to deflate my hopes. I was thinking of getting started right away and having it done in a couple of years. I guess I'll just call up Magrathea and order a custom-made planet instead. [img]/phpBB/images/smiles/icon_biggrin.gif[/img]

    Actually though, is it really such a big deal that the energy conversion would be so slow? I mean, do you think more conventional means would be that much faster? And this one would surely save a lot of trouble, just sit back and watch your bubble world grow, more or less.

    Ok then brainiacs, at 2 pounds per square mile/year, about how long do you think I'd have to wait. I guess we should assume the converted matter is something along the lines of diamond but even stronger, maybe a kind of buckytube material? How thick would it have to be, 100 meters or so?

  11. #41
    Join Date
    Oct 2001
    Posts
    2,677
    Continuing my last train of thought, you know, it doesn't have to be a simple solid sphere. I think it would be possible to create a better design to maximize the strength of the sphere and make it easier to build.

    The way I envision it, start with a lattice of superstrong cables/girders. Stretch them out around the star in a geodesic pattern. This could then be used as a foundation to support a thinner surface covering. It also has an advantage in that once you have the structure down, you can work on laying down the surface at your leisure, a section at a time.

    Also, since you'd probably be rotating it for gravity, the important part of the sphere is around the equator. So make that band very strong and specifically designed for habitation. As you reach further north and south, the sphere can be thinner and less complex. I suppose what I'm imagining is a kind of super-ringworld with a solid center ring and a simple shell of material or even just a lattice to fill out the rest of the sphere.


  12. #42
    Join Date
    Oct 2001
    Posts
    7,732
    I guess I'll just call up Magrathea and order a custom-made planet instead.
    Designed and supervised by Slartibartfast? [img]/phpBB/images/smiles/icon_biggrin.gif[/img]

    _________________
    When all is said and done - sit down and shut up!

    <font size=-1>[ This Message was edited by: Kaptain K on 2002-02-25 02:44 ]</font>

  13. #43
    Join Date
    Oct 2001
    Posts
    3,011
    Pomp and Circumstance, a new bright and shining light, blah blah blah blah, congratulations, etc., Doctor Kaptain K!

    <font size=-1>[Just wanted to add a little fireworks.]</font>

    <font size=-1>[ This Message was edited by: GrapesOfWrath on 2002-02-25 07:15 ]</font>

  14. #44
    Join Date
    Oct 2001
    Posts
    2,677
    On 2002-02-25 02:42, Kaptain K wrote:

    Designed and supervised by Slartibartfast? [img]/phpBB/images/smiles/icon_biggrin.gif[/img]
    Hmm. I hope not. I'd get fjords in all sorts of inconvenient locations. [img]/phpBB/images/smiles/icon_razz.gif[/img]

    And congrats from me too.

  15. #45
    Join Date
    Nov 2001
    Posts
    523
    Just a note - Today 3/2/02 is James Doohan's 82nd birthday - HAPPY BIRTHDAY!!!!

Similar Threads

  1. Replies: 1
    Last Post: 2010-Nov-08, 04:53 PM
  2. Astronomy Without A Telescope – Animal Astronomy
    By Fraser in forum Universe Today
    Replies: 0
    Last Post: 2010-Jul-03, 11:50 PM
  3. Replies: 0
    Last Post: 2010-Jun-01, 01:30 AM
  4. Replies: 0
    Last Post: 2010-May-28, 01:10 AM
  5. Bad Astronomy in Astronomy: Expanding Universe question
    By Crimson in forum Small Media at Large
    Replies: 35
    Last Post: 2007-Sep-26, 08:39 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •