GoldenViper All American 16056 Posts user info edit post |
Quote : | "you people who think we'll be doing planetary mega structures any time soon have no idea where we're really at" |
Where are we actually at?6/1/2008 11:11:21 PM |
Smath74 All American 93278 Posts user info edit post |
spending billions of dollars to send small capsules into low earth orbit is nowhere near where we need to be to even start thinking of building megastructures in space. 6/2/2008 12:05:19 AM |
GoldenViper All American 16056 Posts user info edit post |
Molecular manufacturing could help considerably. If we get Drexler's idea up and running, getting to space will become dramatically cheaper. 6/2/2008 12:44:13 AM |
Smath74 All American 93278 Posts user info edit post |
you are thinking too sci-fi. 6/2/2008 7:37:43 AM |
Rat Suspended 5724 Posts user info edit post |
Quote : | "planetary mega structures" |
I'm talking about a single space elevator. Think of all the billions you'd save on fuel, carbon emissions, money, and time in getting stuff into space.
If you want to dump hundreds of trillions of gallons of liquid O2 into these rockets for an extra 100 years getting a rocket or so per month into space from nasa, have fun. Otherwise, we can get this thing built and daily send materials up / and back down.6/2/2008 8:12:56 AM |
mrfrog ☯ 15145 Posts user info edit post |
Important facts about the space elevator
- We do not have any material that is strong enough to work right now. Any material longer than 2 cm that mankind has ever built in its history is of insufficient strength to density ratio to work as a space elevator material even theoretically.
- The space elevator would take a lot of material. So you use superlight carbon nanotubes - then what? You have to build in extra strength for the payload. Since the length is going to be like 4000 miles, if it's large enough to carry up anything larger than an ant, it is going to take huge amounts of the nonexistent material, which by generous estimates will be an energy intensive material to manufacture.
- The benefit of a space elevator is continuous operation, not capacity. You might be able to take up hundreds of thousands of tons in a year, but if the "packets" you send them up in must be less than say 50 kg, then you can't even send up astronauts with it. The permissible weight of a "packet" will be proportional to the mass of material you use to make it.
All space elevators are not the same. If you want to make this big enough to replace liquid O2 rockets, you're going to be spending more energy than it would have taken to send up the rockets themselves. Otherwise, you have this very thin string that goes up to geocentric orbit which does nothing practical.
Two decades of [fail] by NASA is not sufficient to prove that rocket launches are inefficient methods of delivering something to orbit. In fact, they're not, if you look at just the energy costs of orbital flight they're not that bad. The idea that we should abandon the method entirely for some pie-in-the-sky idea is attempting to fix a problem that doesn't exist with a solution that is much worse.
Before you can even think about making such an elevator, you need decades of experience manufacturing the high-strength materials needed in mass quantities. You need to have already have reached some threshold of orbital launches proving clear economic benefit. You need to have a lot of things that we probably won't have for centuries to come. 6/2/2008 9:39:03 AM |
nastoute All American 31058 Posts user info edit post |
not to say that we are really near the ability to make a space elevator it's not the kind of "mega structure" we're typically talking about
I said planetary, but I might of misspoken... when we're talking about "mega structures" think niven's ringworld size
well, i did misspeak, the space elevator is possible in the next couple of hundred of years or so, dyson whatevers, NO
and I agree, GoldenViper needs to come back down to reality and live with the rest of us
Quote : | "Major : Creative Writing/Revisionist History " |
ahh, there it is... lol
I do like mrfrogs push for the rocket though...
[Edited on June 2, 2008 at 10:02 AM. Reason : .]6/2/2008 9:56:27 AM |
GoldenViper All American 16056 Posts user info edit post |
Quote : | "you are thinking too sci-fi." |
Molecular manufacturing is both possible and probable.
Quote : | "Before you can even think about making such an elevator, you need decades of experience manufacturing the high-strength materials needed in mass quantities." |
You make many solid points, but go too far here. Decades? Progress happens quicker than that. Your next jump from decades to centuries further confuses me.
Quote : | "and I agree, GoldenViper needs to come back down to reality and live with the rest of us" |
Not going to happen. I can predict that with certainty.6/2/2008 10:50:59 AM |
nastoute All American 31058 Posts user info edit post |
i'm going to try not to make fun of you, because we care about the same things
i mean, I love sci-fi, we ALL LOVE THE SCI-FI
but there comes a time when we need to talk about the thing that we love, space exploration, in realistic probable terms
in this way, eventually, all possibilities will become reality
you just have to have an appreciation for time scales though and the realities of the progress of progress 6/2/2008 11:05:03 AM |
Rat Suspended 5724 Posts user info edit post |
Quote : | "The strength and flexibility of carbon nanotubes makes them of potential use in controlling other nanoscale structures, which suggests they will have an important role in nanotechnology engineering. The highest tensile strength an individual multi-walled carbon nanotube has been tested to be is 63 GPa.[58] A 2006 study published in Nature determined that some carbon nanotubes are present in damascus steel, possibly helping to account for the legendary strength of the (almost ancient) swords made of it.[59][60]" |
the moment we have a quick way to fabricate strong carbon, the space elevator shouldn't take more than a decade to finish.
doesn't sound like science fiction to me
\/- oh you will? thanks, and we could use your fat head as the counterweight to hold the structure in orbit. lol
[Edited on June 2, 2008 at 11:19 AM. Reason : \/]6/2/2008 11:09:33 AM |
nastoute All American 31058 Posts user info edit post |
i'll fucking carbon nanotube you 6/2/2008 11:10:10 AM |
Megaloman84 All American 2119 Posts user info edit post |
GV, check out Bob Zubrin's books, The Case For Mars and Entering Space for a realistic, brass tacks engineer's assessment of near and longer term possibilities in space. Highly speculative stuff like ringworlds are cool, but nothing we need to be seriously contemplating at this point. 6/2/2008 12:14:39 PM |
GoldenViper All American 16056 Posts user info edit post |
Quote : | "but there comes a time when we need to talk about the thing that we love, space exploration, in realistic probable terms" |
I am. I only mentioned Dyson spheres in response to the idea of asteroid mining. Molecular manufacturing, a likely advance, will benefit any space exploration scheme dramatically. Diamondoids will be far strong than current materials, allowing for lighter spacecraft. As Drexler writes, the nanotech revolution will make space access affordable.6/2/2008 1:35:55 PM |
Rat Suspended 5724 Posts user info edit post |
sometimes i just want to say: Damn you gravity!!!
but all this technology we're going to develop to get us off the planet is going to teh awesome. 6/2/2008 1:37:34 PM |
GoldenViper All American 16056 Posts user info edit post |
I rather like J. Storrs Hall's idea of a tower a hundred kilometers tall and three hundred kilometers long, with an electromagnetic accelerator on top. Use that a platform to launch whatever you want into space. This would be considerably easier to build than traditional sky hook.
http://www.imm.org/publications/reports/rep016/ 6/2/2008 1:45:40 PM |
mrfrog ☯ 15145 Posts user info edit post |
Quote : | "Molecular manufacturing, a likely advance, will benefit any space exploration scheme dramatically." |
Responding to this, I'd like to quote something from link ^
Quote : | "the structure would require at least ten thousand, and more likely 100 thousand, tonnes of near-atomically-perfect buckytubes or other graphite cable in a tapered form on the order of 80 thousand kilometers long! (enough to wrap around the equator twice)." |
In summary, the reason you need an incredible lead time is because we're not talking about just molecular manufacturing. We're talking about molecular manufacturing on a mega scale (well, okay maybe 'kilo').
Hall's proposal is interesting to read. Way out of practicality and a little full of himself, but still good. It goes a long way to show where the space elevator idea is. Idea is proposed which is veritably much better than the space elevator, but any projection of the costs throw it out into the fantasy world.
And just a tip: don't even mention the Ringworld in a serious conversation about this
You know what material strength this requires? It is orders of magnitude beyond carbon nanotubes, and simply doesn't exist in this universe. I guess it's nice to know to know. But ideas like this simply have no physical basis. Can not happen with any civilization. Nothing more than a writers musings.
Also, a solid Dyson sphere nearly falls into the same category. Look up the strength/density values needed for that one too. They're not impossible, but border on the limits of what our society has available. In real life a Dyson sphere would have to be made of carbon nanotube-like materials. Of course, the 'swarm' idea was made to correct for this and does not have those problems at all, but that would be a natural extension of self replicating life adapted for empty space anyway.
If someone dreamed of something - that means it was convenient for them to think of it at the time. Nothing more.
[Edited on June 2, 2008 at 3:24 PM. Reason : ]6/2/2008 3:23:17 PM |
Rat Suspended 5724 Posts user info edit post |
^ dude i swear to god i thought of that the other day. except not so dense. more like a tube that is thick enough to hold breatheable air and every now and again a city with a forest planted near it. 6/2/2008 3:27:34 PM |
mrfrog ☯ 15145 Posts user info edit post |
Rat, your idea sounds closer to http://en.wikipedia.org/wiki/Stanford_torus But it would depend on how you want to tie up the ends and the size you propose.
I certainly have my own pet designs I like. nastoute has been around long enough he might remember me posting about one or two. By all means, you can spin things, string things, prop things or whatever to create some idea that 'might' work, but what amazes me is how far the people who think of them are from actually comparing the feasibility, which isn't pointless just because they're so far away technologically. 6/2/2008 3:37:00 PM |
nastoute All American 31058 Posts user info edit post |
i kind of like this idea
http://en.wikipedia.org/wiki/Launch_loop 6/2/2008 3:53:18 PM |
Rat Suspended 5724 Posts user info edit post |
that's actually a lot like what i imagined.
except, the one i'm thinking would be a pipe that was the size of earths entire orbit.
let me get out the paint:
edit:
key: this design allows the earth to rotate freely so the structure would orbit the sun as well.
4 space elevators would be nearly touching the structure at all times, all you would need is a small pod to get from the end of the elevator to the super structure and then you can travel around the tube at will.
the moon wouldn't hit too. yay.
[Edited on June 2, 2008 at 4:24 PM. Reason : /] 6/2/2008 4:14:30 PM |
GoldenViper All American 16056 Posts user info edit post |
Quote : | "In summary, the reason you need an incredible lead time is because we're not talking about just molecular manufacturing. We're talking about molecular manufacturing on a mega scale (well, okay maybe 'kilo')." |
According to the theory, molecular manufacturing will immediately jump to the mega scale. Once you build a Drexler-style nanofactory, the process becomes exponential. That nanoflac builds another, which builds another, etc. That why Hall's idea could become reality relatively soon.
As for Dyson spheres, I don't believe the man himself imagined them as solid. No one takes solid Dyson spheres seriously.6/2/2008 5:00:03 PM |
Rat Suspended 5724 Posts user info edit post |
this is pretty good. get up to about 70,000 feet and let er rip!
6/2/2008 6:09:34 PM |
cheerwhiner All American 8302 Posts user info edit post |
but in the episode of Star Trek NG where Scotty comes back that Dyson Sphere had a planet inside it 6/2/2008 8:02:35 PM |
GoldenViper All American 16056 Posts user info edit post |
That was a solid Dyson sphere, right? Star Trek isn't exactly know for being scientifically plausible. In fact, it's some of the softest science fiction you can find. 6/2/2008 8:31:41 PM |
LoneSnark All American 12317 Posts user info edit post |
It was for plot reasons. The Enterprise needed to get trapped inside the sphere (what other form of drama could happen?) and it could have just shot its way out of a soft sphere. 6/2/2008 9:28:28 PM |
Mr. Joshua Swimfanfan 43948 Posts user info edit post |
I wouldn't call a Dyson sphere totally improbable, but any society that has the capability to make one would probably possess the technology to make one impractical. 6/2/2008 11:08:55 PM |
mrfrog ☯ 15145 Posts user info edit post |
same with the space elevator 6/3/2008 9:00:38 AM |
Rat Suspended 5724 Posts user info edit post |
same with "flying" and "nuclear energy" just 100 years ago. 6/3/2008 10:29:29 AM |
Honkeyball All American 1684 Posts user info edit post |
Quote : | "As for Dyson spheres, I don't believe the man himself imagined them as solid. No one takes solid Dyson spheres seriously." |
The shear volume of material involved in making one makes it totally infeasible. Atmospheric processors a la Aliens & Total Recall seem like more realistic options. Heck, it'd be easier to build a second earth than a dyson sphere.6/3/2008 11:46:17 AM |
Rat Suspended 5724 Posts user info edit post |
However, I'm in favor of a dyson partial ring. not a sphere, not even a full ring, just a piece. that should still cover some crazy energy needs. 6/3/2008 11:49:06 AM |
Gamecat All American 17913 Posts user info edit post |
Mankind's future...
LOL 6/3/2008 12:52:15 PM |
GoldenViper All American 16056 Posts user info edit post |
Quote : | "The shear volume of material involved in making one makes it totally infeasible." |
Not necessarily. Consider the Dyson bubble concept, which would require about as much material as the asteroid Pallas. A traditional swarm would take more, but Dyson's logic remains solid. Assuming energy consumption continues to grow, harnessing the ultimate source of energy in the solar system becomes inevitable. Remember that you don't need a full Dyson swarm for it to be worthwhile. Far from it. Each orbiter generates power. Eventually, if you can find enough suitable matter, you cover the star. If not, you cover some significant fraction. An incomplete Dyson sphere would still provide an absurd level of power.6/3/2008 12:53:40 PM |
nastoute All American 31058 Posts user info edit post |
^^
please to explain 6/3/2008 3:07:58 PM |
Rat Suspended 5724 Posts user info edit post |
let's change subject from the future of the space industry to the tech industry.
http://www.engadget.com/2008/01/14/33-megapixel-super-hi-vision-ultra-hdtv-could-be-on-the-air-in/
yes. in 2015 we might have TV's with that resolution. lol.
for you non techies, that means: a single two hour movie = 5.7 TB
or 115 blue rays. 6/3/2008 3:19:23 PM |
mrfrog ☯ 15145 Posts user info edit post |
Quote : | "same with "flying" and "nuclear energy" just 100 years ago." |
If it had been economical enough to make superfast trains, then that would have been so with flying.
And as shocking as it may be, there are people out there who believe nuclear power to be an inferior power source to other options. I'm not in this camp, but the point is that claiming we won't ever need a particular design by the time we can build it depends on the specifics.
And a Dyson 'swarm' doesn't require any given amount of material. It could be an atom thick. Don't know what you'd do with that, but...
Quote : | "Heck, it'd be easier to build a second earth than a dyson sphere." |
lol, this totally works6/3/2008 3:22:01 PM |
nastoute All American 31058 Posts user info edit post |
^^
i wan't better video games
not just prettier 6/3/2008 3:27:56 PM |
Mr. Joshua Swimfanfan 43948 Posts user info edit post |
Quote : | "same with "flying" and "nuclear energy" just 100 years ago." |
How so? Flying clearly made long distance transportation easier and 100 years ago there was absolutely nothing comparable in efficiency to nuclear energy.6/3/2008 3:42:56 PM |
Smath74 All American 93278 Posts user info edit post |
Quote : | "^^
i wan't better video games
not just prettier" |
should have told that to the people who make GTA 6/3/2008 3:53:19 PM |
Honkeyball All American 1684 Posts user info edit post |
Quote : | "lol, this totally works" |
All we're talking about is a large enough satellite that it's placed in an orbit of the sun, instead of a planet. Theoretically, it's all the same concept, just on a larger scale.
Quote : | "Not necessarily. Consider the Dyson bubble concept, which would require about as much material as the asteroid Pallas. A traditional swarm would take more, but Dyson's logic remains solid. Assuming energy consumption continues to grow, harnessing the ultimate source of energy in the solar system becomes inevitable. Remember that you don't need a full Dyson swarm for it to be worthwhile. Far from it. Each orbiter generates power. Eventually, if you can find enough suitable matter, you cover the star. If not, you cover some significant fraction. An incomplete Dyson sphere would still provide an absurd level of power." |
I don't totally disagree with the concept, in fact I agree that if mankind manages to kick it around for a few thousand more years, we'll almost certainly get the vast majority of our energy from the sun. But massive solar arrays in the form of REGULAR satellites seem much more likely bang-buck wise.
What's Dyson's theory on energy transmission from those swarms to the planet? It's pretty easy to figure out if we're talking about a solid, or semisolid sphere... but if it's a cluster, than we're talking about a complicated series of microwave transmitters? And at the scale we're talking about, that's a ton of energy to just point down at the planet in one location.6/3/2008 3:55:28 PM |
GoldenViper All American 16056 Posts user info edit post |
Based on current physical knowledge, I can't foresee anything superior to a Dyson sphere or its equivalent. A star is the ultimate fusion plant. You couldn't do better without injecting material from outside the solar system. What could beat the 3.86E+26 watts the sun produces?
Quote : | "I don't totally disagree with the concept, in fact I agree that if mankind manages to kick it around for a few thousand more years, we'll almost certainly get the vast majority of our energy from the sun. But massive solar arrays in the form of REGULAR satellites seem much more likely bang-buck wise.
[quote]What's Dyson's theory on energy transmission from those swarms to the planet?" |
I believe he assume the species would live in the orbiters. Earth was intended to be consumed for materials along with the rest of the solar system.
Quote : | "And at the scale we're talking about, that's a ton of energy to just point down at the planet in one location." |
Heh. Yes, a small fraction of the sun's power directed at a single point on Earth would cause an extinction level event every second. I doubt we'd do that.
[Edited on June 3, 2008 at 4:03 PM. Reason : poor timing]6/3/2008 3:58:26 PM |
Mr. Joshua Swimfanfan 43948 Posts user info edit post |
Quote : | "Heck, it'd be easier to build a second earth than a dyson sphere." |
That's no moon!6/3/2008 3:58:59 PM |
nastoute All American 31058 Posts user info edit post |
^^ your mom
but seriously, despite my earlier claims that such projects are "the heat", I've always found the idea of making them kind of strange
if we are at that technology level then we need to spend the majority of our resources colonizing the galaxy/galaxies.
also, I always hold out for a form of ftl, but you know... i'm being silly 6/3/2008 4:02:21 PM |
GoldenViper All American 16056 Posts user info edit post |
Quote : | "if we are at that technology level then we need to spend the majority of our resources colonizing the galaxy/galaxies." |
The energy from a Dyson sphere would enable the colonization effort. Until you build the sphere, you're let most of the solar system resources radiate out into the void. It'd be a trade-off. You'd want as much power as possible, but enough material left to create ships.6/3/2008 4:06:43 PM |
Smath74 All American 93278 Posts user info edit post |
that's silly. colonizing the galaxy and spreading out would be MUCH more beneficial than sitting here in our solar system milling about trying to fill up as many energon cubes as we can. 6/3/2008 4:09:37 PM |
nastoute All American 31058 Posts user info edit post |
he does have the right point though
eventually you will want to maximize the collection of energy you recieve from your star(s)
assuming that you don't turn into beings of pure energy before that
or gods
or homosexual gods of pure energy (wat?)
[Edited on June 3, 2008 at 4:13 PM. Reason : .] 6/3/2008 4:12:48 PM |
Honkeyball All American 1684 Posts user info edit post |
Quote : | "I believe he assume the species would live in the orbiters. Earth was intended to be consumed for materials along with the rest of the solar system. " |
A think a little part of me that liked science fiction just died.
Even if we live in the orbiters, we'd still need some way to share power from station to station, something relatively instantaneous and safe. That's probably the missing piece of the puzzle to make it feasible.
That, and thousands of planets worth of raw materials to build the thing with... Up until this point I believe the answer has been "We mine the asteroids"? Really?
Well let me know when you've discovered the formula for transparent aluminum, and we'll talk.6/3/2008 4:17:43 PM |
Smath74 All American 93278 Posts user info edit post |
Quote : | "he does have the right point though
eventually you will want to maximize the collection of energy you recieve from your star(s)" |
i don't know about that... I would think that it would be a LOT more efficient to spread out first and use the places that are available for us to live, and then collect energy as necessary before we build some huge megastructure that would be far to large for our needs. Eventually we might get to the point where we would need every bit of energy from our sun, but we will have run out of room far before then if we don't expand to other worlds and other solar systems first. (besides, why put all of our eggs in one solar system?)6/3/2008 4:23:44 PM |
Rat Suspended 5724 Posts user info edit post |
so what about corporal evolution. do you guys think we've hit the ceiling of our evolution from monkeys to man?
or are there huge leaps that mother nature has in store for us. i think we are near threw, besides minor details. b/c we practically aren't survival of the fittest anymore. we let anybody live with defects.
[Edited on June 3, 2008 at 4:30 PM. Reason : .] 6/3/2008 4:29:48 PM |
GoldenViper All American 16056 Posts user info edit post |
I believe Dyson himself wanted to mine everything: planets, asteroids, moons, whatever. It would take a lot of material. Power could be transfered through microwaves. I know that's how they plan on getting solar power from the moon. I'm sure other possibilities exist. Perhaps the uninhabited stations would have particle accelerators for generating antimatter. I don't think power transmission is the main obstacle!
As for collecting energy versus expanding, why not do both? Build collectors, build probes. Focusing solely on expansion might lead to slower expansion in the long run. 6/3/2008 4:30:11 PM |
nastoute All American 31058 Posts user info edit post |
the idea for efficency of energy collection stems from the difficulty of "getting to the next step"
if getting to other star systems and doing good stuff is deemed nearly impossible (it might be... god I hope not), then we're going to have to work on getting as much as possible from our solar system
for the next scale, if getting to another galaxy is deemd too difficult then were going to have to work on being efficient with the stars and other material in our own galaxy
... 6/3/2008 4:31:00 PM |