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Space Elevator Conference Prompts Lofty Questions

timothy posted more than 2 years ago | from the put-the-new-toys-on-the-credit-card dept.

NASA 212

itwbennett writes "Even the most ardent enthusiasts gathered at the annual Space Elevator Conference on Friday don't expect it to be built anytime soon, but that doesn't stop them from dreaming, planning, and trying to solve some of the more vexing problems. One of the trickiest questions is who's going to pay for the operational costs when an elevator is eventually built. 'It's been nine years we've been looking for someone' to study that, said Bryan Laubscher, one of the leading space elevator enthusiasts and principle at Odysseus Technologies, a company working on high-strength materials."

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212 comments

A virus!? (-1)

CleanThisMinuteness (2437116) | more than 2 years ago | (#37082700)

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Re:A virus!? (0, Insightful)

Anonymous Coward | more than 2 years ago | (#37082758)

Comments are ignored by Google, you stupid asshole.
Do humanity a favor and set yourself on fire.

Re:A virus!? (0)

Anonymous Coward | more than 2 years ago | (#37082772)

I second a Spammer Burning.

Re:A virus!? (0)

Anonymous Coward | more than 2 years ago | (#37082808)

mmm burnt spam!

Re:A virus!? (0)

Anonymous Coward | more than 2 years ago | (#37082978)

Unfortunately not [google.com] but it's nice that a scam alert site comes up first.

Re:A virus!? (2)

nmb3000 (741169) | more than 2 years ago | (#37083170)

Unfortunately not [google.com] but it's nice that a scam alert site comes up first.

Google indexes Slashdot comments, but will not pay any attention to links they contain. All URLs inside comments include the rel="nofollow" attribute, excluding them from participating in search engine ranking.

Re:A virus!? (1)

Anonymous Coward | more than 2 years ago | (#37083026)

A few years ago I installed linux. Then there were no more viruses. If you are having computer problems, I wholeheartedly recommend something better than windows.

Re:A virus!? (2, Funny)

Anonymous Coward | more than 2 years ago | (#37083036)

A few years ago I contracted a virus called linux. It gave me Open Sores.

FYP

Re:A virus!? (0)

Anonymous Coward | more than 2 years ago | (#37083648)

N.B This troll posting has been moderated up courtesy of your friendly representative from Redmond.

“Mopping Up can be a lot of fun. In the Mopping Up phase, Evangelism’s goal is to put the final nail into the competing technology’s coffin, and bury it in the burning depths of the earth. Ideally, use of the competing technology becomes associated with mental deficiency, as in, “he believes in Santa Claus, the Easter Bunny, and Linux.” Just keep rubbing it in, via the press, analysts, newsgroups, whatever. Make the complete failure of the competition’s technology part of the mythology of the computer industry.”

–James Plamondon, Microsoft

Re:A virus!? (0)

Anonymous Coward | more than 2 years ago | (#37083698)

Would be true except nobody cares about Linux on the desktop. People spend a fortune buying macs 'cause they can't stand Windows yet would rather pull teeth out than run Linux.

Is free as in speech really worth something if the speech only sometimes comes out and when it does can barely be understood? That's Linux free speech for you: free as in laryngitis.

plasma cone what? (1)

AwesomeMcgee (2437070) | more than 2 years ago | (#37082706)

atmospheric re-entry be damned, let us consumers pay the maintenance in the form of skydiving tickets!

Re:plasma cone what? (-1)

Anonymous Coward | more than 2 years ago | (#37082950)

atmospheric re-entry be damned, let us consumers pay the maintenance in the form of skydiving tickets!

you're such a stupid nigger i can't believe it

Re:plasma cone what? (0)

Anonymous Coward | more than 2 years ago | (#37083210)

you're such a stupid nigger i can't believe it

An excellent example of a tautology.

Lofstrom loop is better (1)

Anonymous Coward | more than 2 years ago | (#37082722)

Lofstrom loops ares well described on the wiki page for them. Check it out.

Please Mod Parent Up (3, Interesting)

Anonymous Coward | more than 2 years ago | (#37082912)

Launch Loops [wikimedia.org] are indeed far more interesting and practical. Can anyone here explain why space elevators seem to be the more popular idea among the two?

Re:Please Mod Parent Up (1, Insightful)

siddesu (698447) | more than 2 years ago | (#37082998)

It could have something to do with the price tag of maglev tech, which is a little over a brazillion gazillion trillion million dollars per mile of tracks, one way. And I am not even touching the 80 mile high bridge that will have to support it. I'd say at this stage both projects look equally practical.

Re:Please Mod Parent Up (4, Interesting)

Rei (128717) | more than 2 years ago | (#37083052)

A couple hundred miles of maglev track versus tens of thousands of miles of unobtanium cable exposed to micrometeorites, space debris, undamped oscillations, etc. Hmm, which is more realistic...

And I have no clue what you mean by "80 mile high bridge", except to assume that you've grossly understood how a Lofstrom loop works.

The key issues are:

1) A Lofstrom loop requires no unobtanium. It may well be *physically impossible* to create the material needed for a space elevator on Earth, let alone economically practical. After all, the strongest *invididual SWNTs* measured thusfar were barely over 60GPa at the density of graphite, when you need a *bulk cable* that's ideally over 100GPa at graphite densities, preferably over 120.

2) A Lofstrom loop transmits power (the primary lift cost from both systems) at about 50% efficiency. A space elevator beams power at a couple percent efficiency. Hence a Lofstrom loop costs an order of magnitude less to operate.

So we're back to the start. Why a space elevator, apart from the fact that everyone knows of it through sci-fi? Wait, I think I answered my own question.

Re:Please Mod Parent Up (1, Insightful)

siddesu (698447) | more than 2 years ago | (#37083412)

Yep, you're right, I did not perceive the genius at first, I just lazily looked at the picture. In fact, there is no bridge, the structure sustains itself by its own momentum, gravlevitating or whatever. Good luck building that kind of structure without Unobtainium and at only the small price I quoted in my previous post. A 80-km tall bridge won't be much harder.

Re:Please Mod Parent Up (3, Insightful)

mosb1000 (710161) | more than 2 years ago | (#37083340)

A space elevator is essentially a static structure, it does not require any power to stay in place. As such, it is more like a building than a machine. It's much less complex, which means quality control would be much simpler/possible. There are many questions about how you would build a launch loop too. The only real question about a space elevator is the material. They think single walled carbon nanotubes could be strong enough to do the trick. That means the technology is more likely to pan out in the long run. And if you could build it, it could be much cheaper to operate and much simpler to build than a launch loop.

So, in short, the space elevator gets more attention because it is a more compelling proposition, and seems more likely to succeed.

SPACE CADET (IN TRAINING) - WHERE DO I APPLY ?? (0)

Anonymous Coward | more than 2 years ago | (#37082732)

I am ready to run this elevator to space !!

Or build a skyhook (2, Interesting)

MichaelSmith (789609) | more than 2 years ago | (#37082734)

It needs to be strong but nanotubes aren't required. You make a cable about 1000 km long. It has fittings on both ends which vehicles can attach themselves to. It orbits slightly more than 500 km above the ground and rotates its its axis horizontal and at 90 degrees to its orbit. The length and orbital altitude and chosen so that when one end almost reaches the ground it has a low velocity, while the other end is above escape velocity. You use it to exchange mass between the surface of the Earth and a trajectory which will take you to other planets. A dead mass can be sent down to Earth and a vehicle carrying passengers and supplies can be sent the other way.

Re:Or build a skyhook (1)

hedwards (940851) | more than 2 years ago | (#37083088)

The idea is tantamount to expecting to go to the moon by pulling on your own boot straps.

In order for it to work, you'd need to have some energy source to resist the pull of the item you're wanting to lift into space. And by the time you start sending rockets up with fuel to do that, you might as well just use rockets to send the payload into orbit because it's much more efficient.

Re:Or build a skyhook (0)

Anonymous Coward | more than 2 years ago | (#37083162)

go to the moon by pulling on your own boot straps.

Oh man, what if we connected the skyhook to the moon?

Nobel prize please.

Re:Or build a skyhook (3, Insightful)

physicsphairy (720718) | more than 2 years ago | (#37083228)

Well, one idea is that you catch random orbiting junk at the other end, replenishing the lost momentum. In any case, efficiency isn't particularly important. The major limitation on getting things into space right now is construction, launch logistics, etc. If we could somehow be continuously sending things into space, it would be well-worth having to send two or three times the fuel along with.

Re:Or build a skyhook (1)

Ramin_HAL9001 (1677134) | more than 2 years ago | (#37083116)

How can you lift a 1000 Km cable into space, then control where one end of it lands? And how do you get a dead mass back up the other end once your shuttle has gone off and isn't available to counter-weight the dead mass that came back down when it was launched?

Re:Or build a skyhook (1)

MichaelSmith (789609) | more than 2 years ago | (#37083490)

The cable spins end over end. Attach masses to both ends at the same time. One mass at the top of the arc, the other mass at the bottom. Both masses match velocity with and end of the cable. During a half rotation the two masses exchange momentum.

Re:Or build a skyhook (2)

strack (1051390) | more than 2 years ago | (#37083140)

thats a stupid idea. the sheer drag as it plows through the atmosphere repeatedly means itll last only a few orbits, if that. even if the speed was low, the drag would still be large enough to bring it down quickly. and anything you sling into orbit is gonna pull the entire thing down, so your gonna need the same, probably more, thrust to bring it back to that 500km orbit than youd spend just blasting a rocket with that payload on the same trajectory.

Re:Or build a skyhook (2)

0123456 (636235) | more than 2 years ago | (#37083176)

thats a stupid idea. the sheer drag as it plows through the atmosphere repeatedly means itll last only a few orbits, if that.

I'm not entirely convinced. If you rotate it at the correct speed it could have zero velocity relative to Earth at the bottom of the swing and you could pick the orbit so that it picked up payloads in thin air (of course getting the payloads onto something that's rotating like that would be tricky).

Re:Or build a skyhook (2)

MichaelSmith (789609) | more than 2 years ago | (#37083518)

Say you use it to send mass to the moon. For every 1000kg of food, fuel and people you send up, you send down 1100kg of lunar rock. This shifts the the centre of gravity of the rotating tether to a higher altitude every time two payloads are exchanged. Each end of the tether drops down to 10 or 20 km altitude, and at a low speed. Its motion relative to the ground would be mostly vertical. The amount of energy lost on each rotation would be fairly small and could be offset by importing rock from places outside our gravity well.

Putting the whole structure in orbit and spinning it up would certainly be expensive, but it might be possible to build it on the moon and send it down the gravity well.

Re:Or build a skyhook (2)

KonoWatakushi (910213) | more than 2 years ago | (#37083234)

Sadly, since a skyhook is not attached to the earth, it misses one of the key advantages of a space elevator: the earth itself supplying the necessary angular momentum. For an elevator, only potential energy must be supplied, and that rapidly gets cheaper the further up you go. Past geo-synchronous orbit it is entirely free, but velocity still increases linearly with height. (Keep in mind that the kinetic energy is proportional to the square of the velocity; paying for that energy directly is very expensive.)

With a skyhook, not only must you pay for the initial velocity, you can't arbitrarily choose the final delta-v, so there is still a considerable amount of energy that needs to be supplied, compounded with the extra fuel that must be carried to do so. Not to mention the continual input of energy to overcome atmospheric drag and maintain height. (If the up/down traffic isn't balanced, this is even more expensive, so you also need to consider the cost of moving that mass through space in the first place.) It would probably still be an improvement, but it would be complicated and could never hope to match the exceptionally low costs made possible by an elevator.

In terms of practicality, it may not require such exotic materials, but it would be that much more costly to orbit (and impart angular momentum to) such an enormous mass.

Re:Or build a skyhook (0)

Anonymous Coward | more than 2 years ago | (#37083468)

"It has fittings on both ends [...]"

Since the device being imagined does not exist and may never exist in the form being contemplated, it would preserve your credibility a bit to use the subjunctive [wikipedia.org] (sorry if I'm misusing the term). You should say, "It would have fittings on both ends" and so on.

Anytime soon (1)

perpenso (1613749) | more than 2 years ago | (#37082742)

Even the most ardent enthusiasts gathered at the annual Space Elevator Conference on Friday don't expect it to be built anytime soon

Considering that the engineers who will design and build the elevator first need the scientists to figure out the physics and chemistry of the materials required that is a pretty good perspective.

Re:Anytime soon (3, Insightful)

hedwards (940851) | more than 2 years ago | (#37083096)

Projects like this are frequently as interesting, if not more so, for the byproducts that have to be developed in order to make it work.

Delusional mental patients (-1)

Anonymous Coward | more than 2 years ago | (#37082744)

experience no miraculous boost in IQ merely by congregating. And that is the right word since this Space Nuttery is nothing more than a modern-day religion which offers solace to chosen few. We must get off this rock! (Um, the other planets are pretty much just rocks too, and utterly more hostile than the most hostile desert on Earth.) We can't get off this rock so let's imagine dozens of impossible materials and imaginary technologies to a problem only we can see and no one will pay for so we can go to an utterly empty and hostile vacuum!

Amen.

Elevator to nowhere (0)

Osgeld (1900440) | more than 2 years ago | (#37082774)

I get that people want to nerd out and iron the issues out on such a wacky idea

but seriously?

"One of the trickiest questions is who's going to pay for the operational costs when an elevator is eventually built"

its never going to be built! cause its fucking stupid idea, and because outside of a serious brain exercise it holds no value

Re:Elevator to nowhere (2)

The Pirou (1551493) | more than 2 years ago | (#37082834)

Lots of things have sounded stupid by outsiders as demonstrated by the vilification of Galileo by geo-centrists. Should he have let them stop him?

By getting together and starting broader dialogue about the idea of creating a viable mechanism for transit these people are at least working on the 'pseudo-code' for the problem. Whether this particular idea should fail or not, the solutions presented have the potential to act as a fulcrum for broader scientific discovery. Scientific revolutions don't happen by deciding not to attempt to pursue something because it sounds silly given your current understanding of the world around you.

Re:Elevator to nowhere (0)

Osgeld (1900440) | more than 2 years ago | (#37083030)

well right there in the article its talking about driving cars up it ... never mind the MILES of gravity its seriously talking about cars driving up it

Re:Elevator to nowhere (0)

Anonymous Coward | more than 2 years ago | (#37083074)

When they say "cars", they don't mean automobiles. They're using the word in the same sense as an elevator car - a moving container holding people or other things.

Also, you don't measure gravity in miles.

Re:Elevator to nowhere (1)

The Pirou (1551493) | more than 2 years ago | (#37083144)

Don't limit your perspective.
Have you seen 'Minority Report?' Their interpretation of future 'roads' is like a public mag-lev bullet train taken to the individual level. Granted, that's not necessarily the way we're progressing, but it still follows that it's a possibility. Again, this is about writing the 'pseudo-code' that might yield something positive in the future, and deriding it as a wacky idea that shouldn't be taken seriously warrants a "seriously?" itself.

Re:Elevator to nowhere (2)

Osgeld (1900440) | more than 2 years ago | (#37083194)

yea thanks I dont get my future vision from made up bullshit in a special effects house, the age of sifi actually having a real influence on tech is gone, sifi has gotten even more outlandish with its bullshit, and tech has cought up to the point where some dev at apple thinking that compressed music in a large archive is the way of the future, is long gone.

so enjoy your movies past of futures that will never be, I personally will be doing the best I can with what is available

Re:Elevator to nowhere (1)

nmb3000 (741169) | more than 2 years ago | (#37083230)

well right there in the article its talking about driving cars up it ... never mind the MILES of gravity its seriously talking about cars driving up it

I used to be very critical of space elevators as well... until I bothered to read up on the ideas behind them. If you're actually interested in learning more, check out these two articles:

Space Elevator [wikipedia.org]
Space Elevator Economics [wikipedia.org]

As just a quick example, putting a payload in orbit with rockets ranges from $4,000/kg to $40,000/kg depending on the rocket type. Estimates for the cost of electricity to move an elevator into orbit is around $220/kg with current power transfer capabilities, becoming cheaper as that technology improves. And, if you assume that power becomes cheaper to produce in the same timeframe as space elevator components become feasible (ala fusion or something else), this payload delivery cost will be even lower.

Nobody is suggesting we break ground on the base stations today. It's simply an interesting idea for putting things in orbit, and maybe a good goal/benchmark for the development of new high-strength materials.

Re:Elevator to nowhere (0)

Anonymous Coward | more than 2 years ago | (#37083588)

Are they referring to the road-type of cars, or something more similar to ski-lifts? The orbital [memory-alpha.org] tether [memory-alpha.org] from Star Trek Voyager comes to mind.

Re:Elevator to nowhere (4, Informative)

Baloroth (2370816) | more than 2 years ago | (#37082848)

Do you know anything about space elevators? Seriously. They're a great idea. Practically speaking, they are also very difficult, but if we could build one, the cost of traveling to orbit would become relatively speaking extremely cheap (technically, the energy requirements would stay the same. But the delta-v required would become as low as we please, making very cheap and low-power sources effective). Long term, unless we find a much better way to get to space, they are very likely to be built.

I agree that that is a very stupid question. Obviously, whoever uses it would pay for its use. Aka, commercial companies, NASA, military, etc. Since lots of people want to put stuff into space, lots of people could fund its operation .Probably it would be run by a company or government who would charge for its use (preferably, there would be at least two to introduce competition). That part is relatively easy. Its construction, on the other hand, is quite a problem. Financially and technically. However, it is a very good idea. Keep in mind, 150 years ago space travel on rockets was also just an idea in a few peoples minds. Turns out it isn't such a bad idea after all.

Plus, having an actual stairway to heaven would be pretty awesome...

Re:Elevator to nowhere (1)

Anonymous Coward | more than 2 years ago | (#37082878)

"if we could build one"

How about we get to the point where we can build a bridge over a valley somewhere with carbon nanotubes first. Even that is a LONG ways out. Not any of our lifetimes. And that bridge is about 10000X easier to build than a space elevator.

In theory, it's workable (just barely). In practice, the engineering is so far beyond us that it might as well be impossible.

Re:Elevator to nowhere (1)

0123456 (636235) | more than 2 years ago | (#37083190)

In practice, the engineering is so far beyond us that it might as well be impossible.

Nearly impossible? OK, we might have to wait two hundred years then.

Re:Elevator to nowhere (0)

Osgeld (1900440) | more than 2 years ago | (#37083034)

yea like driving cars up it as in TFA, you have MILES of gavity to defeat and these clowns forgot gravity

its now how I see the world that makes it stupid, its the god damned facts of the world that makes it stupid

Re:Elevator to nowhere (0)

Anonymous Coward | more than 2 years ago | (#37083046)

yea like driving cars up it as in TFA, you have MILES of gavity to defeat and these clowns forgot gravity

its now how I see the world that makes it stupid, its the god damned facts of the world that makes it stupid

Do you imagine some redneck in a v8 with a gun rack on the back taking his tractor tired 4x4 up a vertical road? Seriously.. the word car can be more than just "automobile" ..

Re:Elevator to nowhere (0)

Osgeld (1900440) | more than 2 years ago | (#37083062)

um yea number one definition of car is automobile followed by trolly, just because in your firefly rerun world car != automobile does not make up for the fact that for the last 100 or so years car = automobile

k thanks

Re:Elevator to nowhere (0)

Anonymous Coward | more than 2 years ago | (#37083124)

Nowhere in your little rant did you address the fact that the TFA's use of the word car doesn't mean automobile. I take it you've never heard of train cars or elevator cars? Hint: "elevator cars"..."space elevator"...notice the connection?

Re:Elevator to nowhere (1)

Arlet (29997) | more than 2 years ago | (#37083166)

Space junk is already becoming a problem. Imagine what would happen if it were extremely cheap to put stuff in orbit...

Re:Elevator to nowhere (0)

Anonymous Coward | more than 2 years ago | (#37083226)

space junk is only a problem for people who go to space, you are arguing that we should not go to space to avoid space junk, which would also assure that no one would be there to care about how clean the orbit is.

Space junk problems can be dealt with, and will have to be if we are going to leave earth.

I hope it is so cheap to put stuff in orbit that a freaking junk ring visible in the light of day forms.

Re:Elevator to nowhere (1)

Arlet (29997) | more than 2 years ago | (#37083232)

you are arguing that we should not go to space to avoid space junk

No, I didn't.

Re:Elevator to nowhere (0)

Anonymous Coward | more than 2 years ago | (#37083430)

The sunk costs of a space elevator would be fucking gigantic, though (18 billion? So, what, figure on 180 billion when it's finally budgeted and 10 times that to get it finished?) How do you price it in that case? If you price it above the cost of a rocket, you get nothing and you go bankrupt. If you price it too low and demand doesn't keep up with your plans, you still go bankrupt.

This could end up being another Iridium, if it ever happens and is expected to be self-supporting. The initial investors bear almost all the cost, the project goes bankrupt, then is sold for a fraction of what it actually cost to the parties who will run it profitably (because they didn't pay the cost of building it).

Re:Elevator to nowhere (2)

sunspot42 (455706) | more than 2 years ago | (#37083484)

The Shuttle program and the ISS alone have cost us north of $200 billion.

With a space elevator, you could conceivably haul the components to build something as large as the ISS into orbit in just a month, for less than the cost of a single Shuttle launch.

Given that the cost differential between launching on chemical rockets and hauling cargo up on a space elevator is THOUSANDS of dollars a kilogram, you can pretty much guarantee that a space elevator will turn a profit. It'll cost around $200-$300 a kilogram to haul payload into orbit with a space elevator, compared to $4,000 and up - way up - with rockets. The operators of a space elevator could charge $3,500 a kg and pretty much monopolize the entire launch business, pocketing $3,000 a kg with each payload.

At least until somebody else builds a space elevator...

Too Slow. (1)

Colin Smith (2679) | more than 2 years ago | (#37083542)

"But the delta-v required would become as low as we please, making very cheap and low-power sources effective"

By that you mean slow => With very poor throughput.

Poor throughput means not economically viable. Which means yet another boondogle which your average spud is going to have to pay for.

Re:Elevator to nowhere (0)

Anonymous Coward | more than 2 years ago | (#37082880)

The Space Elevator will be built:

"50 years after everyone stops laughing"

Sir Arthur C. Clarke

Re:Elevator to nowhere (3, Insightful)

dvice_null (981029) | more than 2 years ago | (#37083188)

"The aeroplane will never fly."

— Lord Haldane, Minister of War, Britain, 1907 (yes, 1907).

"No flying machine will ever fly from New York to Paris ... [because] no known motor can run at the requisite speed for four days without stopping."

— Orville Wright, c. 1908.

"The whole procedure [of shooting rockets into space] . . . presents difficulties of so fundamental a nature, that we are forced to dismiss the notion as essentially impracticable"

— Sir Richard van der Riet Wooley, British astronomer, reviewing P.E. Cleator's 'Rockets Through Space,' in Nature, 14 March 1936

$18B (1)

Swanktastic (109747) | more than 2 years ago | (#37082780)

The article suspects a space elevator could be built for $18 Billion? And they're worried about doing a study to explore who will pay for it? That much money is budget dust for any major country. Once the technology is there, I'm sure Boeing or Bechtel will be more than happy to take taxpayer money to work on the project and "create jobs."

Re:$18B (3, Informative)

Anonymous Coward | more than 2 years ago | (#37082836)

That number is way lowballed. What, are they thinking the price of the nanotube cable is comparable to the market price of carbon?

Anyone dumb enough to pay to build a space elevator this early in the game will lose their money.

Seriously, it's an elevator from the ground to one point in geosynchronous orbit. A payload released at almost any other altitude will need reaction mass to establish a stable orbit, most of which will be expended in the direction of the cable and thus wear it down. (The exceptions are payloads released near geosynchronous orbit which will establish elliptical or parabolic orbits.) Finally, other satellites and debris at lower orbits especially, will impact the cable, both damaging it and setting up waves which will need to be safely dissipated somehow. A paint chip at 500 miles up is going to hit at around 17k miles/hr. and will have plenty of kinetic energy that needs to go somewhere.

Commercially, this is useless, even if you could build it easily and cheaply. It's an engineering nightmare, and no amount of focus on the easy parts of the design -- and the material is the easy part -- will change that.

Realistic that carbon nanotubes won't cost much (1)

Anonymous Coward | more than 2 years ago | (#37082900)

That number is way lowballed. What, are they thinking the price of the nanotube cable is comparable to the market price of carbon?

They were probably thinking that the US and Europe will spend 100s of billions in R&D to discover the science, engineering and manufacturing processes necessary; then China will just rip off the research and manufacture at prices that only need to reflect the actual production costs.

Re:$18B (1)

TaoPhoenix (980487) | more than 2 years ago | (#37082852)

AC below has key points, but I am responding to you in a different vein.

I'll let you have your 18 billion to build it, but it's the "leading edge" of another 100 billion in support industries. "A Cable to lift what? To where?"

Re:$18B (1)

myowntrueself (607117) | more than 2 years ago | (#37083538)

The article suspects a space elevator could be built for $18 Billion? And they're worried about doing a study to explore who will pay for it? That much money is budget dust for any major country. Once the technology is there, I'm sure Boeing or Bechtel will be more than happy to take taxpayer money to work on the project and "create jobs."

Sure, the Yanks could borrow some more money from China.

No usable tether in sight (0)

Anonymous Coward | more than 2 years ago | (#37082812)

The elephant in the room is the tether. As long as there's no tether a few meters long in a labarotory, you don't even have to think about any other aspect of a space elevator.

The major issues and such (4, Informative)

JoshuaZ (1134087) | more than 2 years ago | (#37082814)

Anyone interested in this issue should read the NIAC report http://www.spaceelevator.com/docs/521Edwards.pdf [spaceelevator.com] which discusses the issues in detail and the technical problems. Space elevators would make space travel much cheaper. But the technical issues are immense. The NIAC report carefully outlines the major issues and how they might be handled. We would need to make extremely high quality carbon nanotubes at an immense scale. We also would need to put into space a structure orders of magnitude larger than anything we've put in space. Indeed, a space elevator would be one of the largest physical structures ever made by humans. And the engineering hurdles, such as the problems of wind in the lower atmosphere, are massive. But there's nothing about the idea that is physically impossible. The primary issues are issues of scale. And the issues are being worked on. Right now, there's a lot of work on making carbon nanotubes of high quality in a large scale. Since such nanotubes would have many different applications there's a lot of funding for that and that will likely be extremely beneficial to humanity well before it scales up to anything near that needed for a space elevator. Since the nanotube manufacturing is the primary technical hurdle, this is a good thing. I doubt we will see a space elevator in my lifetime, but maybe my children, or their children, will see it. And on that thing ribbon, space travel will finally become as cheap as so many have envisioned it.

Re:The major issues and such (1)

JoshuaZ (1134087) | more than 2 years ago | (#37082914)

And on that thing ribbon

Ugh. Need to pay more attention to preview. Replace "thing" with "thin".

Re:The major issues and such (1)

Anonymous Coward | more than 2 years ago | (#37082958)

We also would need to put into space a structure orders of magnitude larger than anything we've put in space.

So all they need to do is build a second space elevator to put it up there...

Does a space rope have the same physics? (1)

GoodNewsJimDotCom (2244874) | more than 2 years ago | (#37082830)

Imagine a large object with thrusters orbiting with a rope dropped from it. I'm thinking that the top of the rope must be able to hold the tension of the entire rope, thus it is the same thing as the base of an elevator holding up the entire weight, correct? This is just something I wondered about.

Re:Does a space rope have the same physics? (1)

Ironchew (1069966) | more than 2 years ago | (#37082918)

From my cursory understanding of space elevators, the section in geostationary orbit will have the most tension (and subsequently the most cross-sectional area for handling that tension), and the center of mass will be at geostationary orbit, which possibly involves a tether going down to Earth and something else of equal mass in high Earth orbit. Presumably, the weight of the lower end will be canceled by the centrifugal force of the upper end.

Re:Does a space rope have the same physics? (1)

hedwards (940851) | more than 2 years ago | (#37083126)

That's really a problem, you need to expend energy to keep the satellite in orbit and you need to have energy to raise the payload. Which unfortunately, is liable to be source of the fuel to keep the satellite in orbit. If you've got another means of fueling the satellite to keep it in orbit, you're probably going to be better off using that to get things into space.

Trying to use cable under tension in a scenario like this is never going to work without a major revision to the laws of thermodynamics. It is how ever conceivable that something like this could be achieved with an exceptionally tall tower. Which would be extremely difficult to do, but is at least within the realm of possibility as the force to keep everything in place would come from compression rather than tension.

panax (0)

Anonymous Coward | more than 2 years ago | (#37082874)

object with thrusters orbiting with a rope dropped from it. I'm thinking that the top of the rope must be able to

Pfft (0)

Anonymous Coward | more than 2 years ago | (#37082890)

A space elevator is a ridiculously absurd idea. Next some goofball scientist will propose a pneumatic tube to Mars. Pfft.

Substantial Progress being made (4, Interesting)

mbone (558574) | more than 2 years ago | (#37082936)

One of the interesting things about this conference (which I attended) is that nanoscience researchers on Friday reported substantial improvements in the ability to make carbon nanotubes. They can now "grow" 1 cm nanotube mats, which can be spun into fibers. This is a substantial improvement from even 1 year ago.

I still think that a terrestrial space elevator is a decade out, but this year has convinced me that it is coming much faster than a lot of people think.

Re:Substantial Progress being made (2)

AGMW (594303) | more than 2 years ago | (#37083626)

I still think that a terrestrial space elevator is a decade out, but this year has convinced me that it is coming much faster than a lot of people think.

If we actually return to the moon, might a space elevator be more practical there? Could we do that now?
What about Mars ... how close are we to using a SE there?

Music (1)

k31bang (672440) | more than 2 years ago | (#37082968)

Like what kind of music to play on the way up?

Re:Music (1)

Anonymous Coward | more than 2 years ago | (#37083104)

Or what happens when some kid presses the buttons for floors 150-975 then gets off on the second floor?

No Elevator for 150 years ?!? (1)

Dopeskills (636230) | more than 2 years ago | (#37082984)

From the article: He was reluctant to guess when a space elevator could actually begin to be built. "We try not to be narrow-minded and say it won't happen for 150 years. Breakthroughs in technology innovation occur on a daily basis," he said.

Who's going to pay (1)

macraig (621737) | more than 2 years ago | (#37083000)

Since it will be shared infrastructure like our roads, the public should retain ownership rather than some for-profit corporation, and the contractors we hire to build it should be thus paid with a tax or bond. Of course the same should have been done with telecom infrastructure (and then we'd have true neutrality of the wires).

Re:Who's going to pay (1)

vux984 (928602) | more than 2 years ago | (#37083112)

I agree. But in the real world even crucial regular bridges are being built by for-profit corporations ... for profit.

Re:Who's going to pay (1)

macraig (621737) | more than 2 years ago | (#37083174)

That's what happens when there's no Eisenhower figure to step up and generate consensus. Yeah, people thought Obama was gonna be that type of figure, but it's not happening. (Eisenhower was a Republican, though perhaps Republicans were less cartoonish back then and acknowledged that taxes and "socialization" were practical for some things.)

Re:Who's going to pay (1)

0123456 (636235) | more than 2 years ago | (#37083200)

Eisenhower was a Republican, though perhaps Republicans were less cartoonish back then and acknowledged that taxes and "socialization" were practical for some things.

No, they just hadn't seen clear proof back then of what a disaster socialist policies always are in the long term.

Re:Who's going to pay (1)

meglon (1001833) | more than 2 years ago | (#37083394)

Tell that to China, who's currently kicking our asses. Eisenhower actually knew what socialism was as well, instead of just using the word for anything he disagreed with, unlike the current crop of fucking fascist conservatives.

list of countries by nominal GDP per capita (1)

Anonymous Coward | more than 2 years ago | (#37083722)

1 Luxembourg (socialist) 108,832
2 Norway (socialist) 84,444
3 Qatar (oil money) 76,168
4 Switzerland (socialist) 67,246
5 United Arab Emirates (oil money) 59,717
6 Denmark (socialist) 56,147
7 Australia (socialist) 55,590
8 Sweden (socialist) 48,875
9 United States (capitalist) 47,284
10 Netherlands (socialist) 47,172
11 Canada (socialist) 46,215
12 Ireland (socialist) 45,689

not seeing it dude

We should use our old rockets first (2)

iamacat (583406) | more than 2 years ago | (#37083080)

Our lack of progress in space exploration has more to do with losing the will than limitations of technology. We could have launched a mission to Alpha Centauri by now if we pursued project Orion with modern advances to material science and optimized computer control of propulsion. If we are not doing that, who is to say we will build a space elevator even if the technology is feasible?

Re:We should use our old rockets first (1)

Ambvai (1106941) | more than 2 years ago | (#37083128)

Which reminds me of a story I came across once-- it was basically the journal of an explorer who left Earth to some distant system with the intent to beam information back and start the colonization of the universe. Turns out, when he [and the rest of the crew] got there, space travel had advanced so much that he was welcomed as an artifact that only historians cared about while his trip amounted to nothing more than a footnote in the history books. (Plus a little extra human interest about his wife and kids being one of the first colonists on the planet and having long since died.)

Re:We should use our old rockets first (1)

Arlet (29997) | more than 2 years ago | (#37083292)

We could have launched a mission to Alpha Centauri by now if we pursued project Orion

I don't think the plans for project Orion involved slowing down at the destination, so it would be a rather pointless exercise of zipping through the Alpha Centauri system at 0.03 c, and hopefully taking a few blurry pictures of a planet before entering interstellar space again.

Chemical bond strength vs Gravitational strength (2)

John.P.Jones (601028) | more than 2 years ago | (#37083100)

I was thinking about how the energy of chemical rockets is just barely sufficient (given fuel mass) to make chemical rockets that can escape Earth's gravity well. I'm not sure of the exact headroom but my understanding is that it is fairly tight. From what I have read on the strength of nanotubes, they too are theoretically just strong enough to barely make a space elevator a possibility (if we could manage to weave them into a macro-fiber without significant losses.) If this turns out to be the case I wonder if there is a connection between these two methods and the strength of chemical bonds to overcome the gravitational potential of our planet. Need it be so that these two very different ways of utilizing bond strength achieve a similar maximum gravitational field that they can overcome? And even more speculatively could the fact that the gravitational field of the Earth is near this value be important in the suitability of it to life?

Re:Chemical bond strength vs Gravitational strengt (0)

Anonymous Coward | more than 2 years ago | (#37083202)

Hexapodia the key insight?

Re:Chemical bond strength vs Gravitational strengt (-1)

Anonymous Coward | more than 2 years ago | (#37083470)

what the fuck are you talking about, that isn't even english

Re:Chemical bond strength vs Gravitational strengt (1)

UCSCTek (806902) | more than 2 years ago | (#37083574)

That's quite the stretch.

Naively, I would say the important comparison is between the scale of thermal energy available on Earth to organic bond strengths. I don't see gravity being a large issue.

Re:Chemical bond strength vs Gravitational strengt (0)

Anonymous Coward | more than 2 years ago | (#37083680)

Interesting point. Carbon-carbon bond energy is indeed pivotal to both methods.

I like Launch Loops myself. (2)

Soralin (2437154) | more than 2 years ago | (#37083206)

http://en.wikipedia.org/wiki/Launch_loop [wikipedia.org] Launch loops are basically a big cable, supported magnetically in a vacuum sheath, and accelerated up to high speeds (14km/s+), it could be set up as a 2000km long track along the ground, about 80km up. Since it's moving faster than escape velocity, it would appear to move away from the ground, since the ground is curving away from it faster than it's moving. so it would just need to be tethered to put it into a nice flat path, and could be magnetically looped around and sent back the other way at the end stations. A craft to be launched could just produce a magnetic field, and it would be pulled along at 3g or so, and could let go when it got up to it's desired speed, with a small rocket to circularize it's orbit at higher than 80km, if it's not headed off at escape velocity.

It solves a number of issues that are problems for a space elevator, like how to get something to climb up a tether, or get power to it, which can be done relatively easily for a launch loop, since it could just pull power off the grid whenever it's convenient, and store it in the motion of the cable itself. And it doesn't need any new materials, or really strong ones or anything like that. Not to mention, being much faster to get to orbit, but still suitable for acceleration-sensitive cargo, such as humans. And it can launch quite a bit more material/time then a space elevator can, at a cheaper price. Mainly limited just by the amount of electrical power it has available, and at high power levels, by the need for the cable to cool down between launches.

Only major downside would be that it isn't statically stable, there would have to be dynamic control of the rotor at the end stations, given that it's all just supported and directed magnetically. And it would need to remain powered to keep it from eventually collapsing.

Will the Door Close button work? (1)

kawabago (551139) | more than 2 years ago | (#37083496)

It would be a nice to have at least one elevator on the planet where that button worked.

why not build a launch loop? (0)

Anonymous Coward | more than 2 years ago | (#37083692)

http://en.wikipedia.org/wiki/Launch_loop

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