Obayashi To Build Space Elevator By 2050 488
mattr writes "Japan's Obayashi Corp. has announced plans to build a space elevator by 2050. They are famous for wrecking skylines with the over-sized bullet train station in Kyoto, the world's tallest self-supporting tower Tokyo Sky Tree and just recently, the beginnings of the Taipei Dome. It will take a week at 200 kph for your party of 30 to reach the 36,000-km-high terminal station, while the counterweight [swings along at] 96 km high, a quarter of the way to the Moon."
Is that so? (Score:4, Insightful)
It would be easier to believe that "Japan's Obayashi Corp" are out of their mind if we would have a link to this on their own web site.
Re:Is that so? (Score:5, Informative)
Well, here's [obayashi.co.jp] a list of some of their previous projects.
Re:Is that so? (Score:5, Funny)
Kenny G (Score:5, Funny)
if you think "that guy" who ate the burrito is bad..
just wait until you find out that there is only 1 song played over ... and over..
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A Walk in the Black Forest?
http://www.youtube.com/watch?v=gS15ACUhTww [youtube.com]
Tra-la-la.... (Score:5, Funny)
Nope, this one.
https://www.youtube.com/watch?v=i1EG-MKy4so [youtube.com]
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It will be worse. Remember, this is Japan. It'll be J-Pop.
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http://www.youtube.com/watch?v=QOJzahgbVUg [youtube.com]
Re:Kenny G (Score:5, Funny)
I'm more worried that some idiot will press all the buttons so it stops at every floor.
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The climber has to have food, toilets, sleeping facilities if you are going to take a week to get to GSO, so it's going to have to be more like a mini-hotel (or at least a mini-space station) than an elevator car. As it happens, the Japanese have some experience with mini-hotels [yesicanusechopsticks.com].
Re:Is that so? (Score:5, Informative)
The climber has to have food, toilets, sleeping facilities if you are going to take a week to get to GSO, so it's going to have to be more like a mini-hotel (or at least a mini-space station) than an elevator car.
Like a 'mini hotel'? You've never travelled across Russia by train. Those trains have toilets, sure. Sleeping facilities, sure. Dining cars, sure. But 'mini-hotel'? No. It'd be very cool if the 'space elevator' had coal-fired samovars in every carriage though!
Re:Is that so? (Score:4, Funny)
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The Shitsumi dam?
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Well building an unprecedentedly epic-sized space elevator based on technology that only exists so far in science fiction should be no different than building a big dam. I'm placing a huge buy order on their stock even as we speak.
Bring it on (Score:5, Interesting)
Re:Bring it on (Score:5, Funny)
Not if you write it down. I have kept a record of these predictions. None of them came true. E.g. in 2005 it was predicted that by 2006 we should have invented material for space elevator cables... still waiting for that.
None of the predictions I have monitored have come true. Some have changed the schedule, some have completely disappeared. But no worries, soon we have contacted ET, have eternal lives and we drive with flying cars. It is unfortunate that the Internet crashed a few years ago, but at least we don't need to worry about spam.
gotta love the attitude (Score:5, Insightful)
It probably won't hurt your corporate image too much to bolster some idealism every once in a while.
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Not going to end well... (Score:5, Insightful)
It's bad enough sharing a lift with 5 or 6 people for 30 seconds, let alone sharing one with 30 people for a week.
Re:Not going to end well... (Score:5, Insightful)
If people can live on a sub for months at a time they'd be able to live on an elevator for a week. I assume these people wouldn't be randomly plucked off the street and would undergo some form of training resembling existing astronaut programs.
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It would start at 1 g on the Earth, and rapidly decline. The last 1/2 of the trip or so would be in pretty light gravity (0.01 g or less) declining to zero at geostationary altitude.
Good luck and I want the 13th ride up (Score:5, Insightful)
I wish them luck and hope the technology is ready before I'm too old to ride the thing.
Forecast for this thread. 56% never gonna happen. 10% certain it will happen. 18% about how impossible it is. and the rest finding a way to blame MS for the failure.
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You forgot, "Does it run Linux?", "Imagine a Beowulf cluster of these", "It's good for Global Warming", "It's bad for Global Warming" and "In Soviet-Japanese space, Obayashi elevators YOU!"
Re:Good luck and I want the 13th ride up (Score:4, Funny)
You left out the most relevant one:
1. Announce plan for space elevator
2. ???
3. Profit
But I hope they do work out step 2.
Re:Good luck and I want the 13th ride up (Score:4, Insightful)
Usually step 2 is get investors believe you and give you lots of money. Note that to profit, you don't need to actually manage to build the space elevator. You just must make sure that it doesn't look like fraud.
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"What I wonder is how they would get the cable up there."
They'd rather try to get the cable down here, I presume.
That means, they might prefer to manufacture two cables up there in geo-stationary orbit, then lowering one end of cable #1 down to earth's surface (this might still be a challenging task, though), sending one end of cable #2 even farther outwards, for use with the counterweight.
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You forgot, "Does it run Linux?", "Imagine a Beowulf cluster of these", "It's good for Global Warming", "It's bad for Global Warming" and "In Soviet-Japanese space, Obayashi elevators YOU!"
I think I can tell when I'm being stereotyped.
Um...no, I did not forget any of those responses.
I was just *too* busy welcoming our new space-elevator overlords and their pet sharks with lasers on their heads. Furthermore, not to be an English Nazi, but...
Re:Good luck and I want the 13th ride up (Score:5, Insightful)
Even if they don't do it, I'm pretty sure in the process they're gonna find/invent some cool stuff that will probably make them a shitload of money. They are doing exactly what all technology companies should be doing: push the limits and try the impossible. It's always a win-win idea.
Re:Good luck and I want the 13th ride up (Score:4, Insightful)
They are doing exactly what all technology companies should be doing: push the limits and try the impossible. It's always a win-win idea.
History is littered with the remains of companies who tried to push the limits, attempt the impossible, and failed. True, pushing limits can be extremely rewarding and is the foundation of technical progress, but it's by no means the panacea you imply!
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To pretend for a moment that this is serious, while assuming for the moment that most of the Slashdot audience wishes it could be...
In "Beyond the Fall of Night" Arthur C Clarke and Gentry Lee showed a "pinwheel", which looked to me to be technologically simpler than a full space elevator, though it had its own problems. My interpretation of a pinwheel is that it's a rotating tether in orbit. The orbit and rotational speed are adjusted such that when an end of the tether is at its lowest point its positio
Re: Rotating cables (Score:5, Insightful)
Aerospace engineer who has worked on orbital tether design speaking here.
A cable with a tip velocity of 30% of orbital speed is feasible with existing materials. Since the center of the cable is at orbital velocity by definition, the tip is then at 70% of orbital velocity at the bottom of it's rotation. A vehicle coming from the ground then needs half the kinetic energy as a full ground-to-orbit one does (Kinetic energy goes as 0.5 times velocity squared). That makes single stage launch vehicles very feasible. If the tip is at 1 gravity, then the cable radius is 516 km, and the center would be at an altitude of 750 km or thereabouts, so it does not see too much drag at the low point. Half a rotation later (12 minutes) at top of the rotation, you can let go, and now be going at 130% of orbit velocity, which is nearly GEO transfer or escape. Escape is 141% of orbit velocity.
If you wanted to get to zero g, then it's a 516 km ride, which beats the fuck out of a stationary elevator. The elevator will be heavy relative to the vehicles coming up and down, but you need onboard propulsion to make up for traffic differences. Anything going up tends to lower the elevator orbit, anything going down tends to raise it. Whatever is left over you need to make up, preferably with an efficient electric thruster. Arrival means landing on a platform that is at one gee. With modern GPS and laser navigation, that should be fairly easy. Make the platform hundreds of meters wide if you need a bigger target. Missed landings just means the vehicle heads back down sooner than it was supposed to. It should not present a safety problem.
Building something like this is a bootstrapping task. Start with a small rotating station, and extend cables from it. Keep adding sections of cable one at a time. Get your cable from near earth asteroids which have carbon, so you don't have to launch the whole thing from Earth. As the thing grows, the velocity to reach it from the ground goes down, so the payload a vehicle can carry goes up.
Great concept except for .... (Score:3, Insightful)
2. Neither Japan nor any Japanese company has the financial solvency to undertake such an effort
2. No no wants to spend a week in an elevator even if it means you get to go into orbit. Christ I can barely make it to the 15th floor without some jackass farting. A whole week. Don't think so.
Every so often some company in need of cashflow creates some nonsensical grandiose concept in the hopes of securing ignorant investor funding (See Moller flying cars). And such companies usually have spent the bulk of the cash on P.R. - hence the slashdot article.
It's bullshit. It's always bullshit.
Counterpoint (Score:5, Insightful)
The fact that we don't have the necessary structural materials yet to actually make a space elevator.
And we'll continue not having them until someone pays to build a space elevator and does the needed research. By 2050 it's not impossible to think materials will be around to make this feasible.
Neither Japan nor any Japanese company has the financial solvency to undertake such an effort
Possibly, hard to say. They put up some really large buildings. They could get a huge loan.
No one wants to spend a week in an elevator even if it means you get to go into orbit.
I would happily pay 20k to go to said stationary station for a few days. Even if it took a week to get there in cramped quarters.
By then there may be a number of cheaper options to visit pace though, Virgin Galactic is making a go at it. I really only want to go up if I can spend a day or two though, so mere flights up and down do not interest me much...
Re:Counterpoint (Score:4, Insightful)
By then there may be a number of cheaper options to visit space though, Virgin Galactic is making a go at it.
I dont believe they will ever be cheaper. Also, they're not even reaching low earth orbit yet (at the moment they're scraping 110km or something).
Space elevators on the other hand will go up to geostationary at least (as the summary says: 36000km), and they're far more efficient, I suspect (rocket motor spewing stuff all over the place versus electrical lift running up a tether).
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Space elevators on the other hand will go up to geostationary at least (as the summary says: 36000km), and they're far more efficient, I suspect
I'm sure they are more efficient at getting people up and down (especially with a counterweight) when built, but it seems like they have a ton of up-front debt in terms of materials that have to be lifted up by said rockets to average out with cheaper trips up once it is running...
SpaceX seems to be doing a good job really driving down the rocket motor cost side.
Tha
Re:Counterpoint (Score:5, Insightful)
Space elevator : Initial cost is very very high but once built the running costs are negligible
Rockets : Initial cost is high but not that high, running costs are high forever, economy of scale will never kick in to any reasonable degree
Once you have built a space elevator, all rocketry for lifting will be obsolete - most of a rocket is there to lift the rocket into orbit not the payload ... a space elevator will be externally powered so will not need to be any heavier than needed to climb the cable ..and you might be able to drive it and fund it with materials coming down (mining the asteroids)
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Re:Counterpoint (Score:5, Informative)
Umm, no.
Below the terminus at GEO, the elevator is moving at less than orbital speed. Above the terminus (all the way to the counterweight), it is moving at more than orbital speed.
This can be taken advantage of to deploy things to positions in LEO (release something at just the right altitude along the space elevator, it'll drop down to a perigee at the altitude you want it, then a small boost from a conventional rocket, and you're in a circular orbit in LEO. At much lower cost than a rocket from the ground.
Likewise, it can be used to toss things into the outer system - the counterweight is moving at far above escape speed (~7000 m/s at 96000 km), so you can just let something go there, and it'll be heading off in the general direction of Jupiter. It won't go as high as Saturn's orbit without a higher counterweight, of course, but lower aphelions are possible by releasing at a lower altitude than the counterweight...
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Well, in Europe, most long-distance train tickets are much more expensive than the comparable flight. I would take that as a strong indication that planes are in fact cheaper overall than trains. I don't really know why, though.
Re:Counterpoint (Score:5, Informative)
Most railways in Europe are owned and operated by state-sponsored monopolies. In The Netherlands there are small openings for other railway companies and they are generally cheaper, more reliable and providing much better service.
Fun case: Deutsche Bahn wanted to extend their high-speed network into The Netherlands (to the North) where the current monopolist has no intention of providing service. But since they aren't allowed into Germany they were able to block the new railway into The Netherlands through lobbying. The northern provinces of Holland were quite mad but couldn't do much about it.
"Running costs are negligible" (Score:5, Interesting)
Vandalism, terrorist or not, and theft are probably the biggest issues. Carbon fibre hasn't taken over for the cables of suspension footbridges for just that reason.
Re:"Running costs are negligible" (Score:5, Funny)
Vandalism, terrorist or not, and theft are probably the biggest issues.
"The police are looking for the stolen space elevator. All citizens noticing their neighbor trying to hide a suspiciously large elevator in his backyard are requested to report this to their local police station."
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Space elevator : Initial cost is very very high but once built the running costs are negligible
Rockets : Initial cost is high but not that high, running costs are high forever, economy of scale will never kick in to any reasonable degree
Exactly that's also why trains and not planes are such a success in the States.
They are for cargo, by a massive margin. Trains for passenger travel don't work all that well in the US for a simple reason -- the US is huge. The balance of cost vs travel time works out in favor of air travel for most people in the US.
If cross-country plane tickets cost $250k, you'd see a lot of people taking a train, and maybe flying a regional plane from a train station to where they're going.
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The burj khalifa (tallest manmade structure) is less than a KM high. It took 5 years to build the exostructure. In some ways, the space elevator will be simpler, in some ways more complex, but assuming they can build it ten times as fast, they only needed to start a few years ago!
Re:Counterpoint (Score:5, Insightful)
And we'll continue not having them until someone pays to build a space elevator and does the needed research. By 2050 it's not impossible to think materials will be around to make this feasible.
Not true. The utility of a 63GPa material with the density in the 3000-2000kg/m3 department is so ridiculously awesome that its is indistinguishable from magic compared to today's materials. Think *easy* to build SSTO RV rockets for starters. Even if expensive its just plain awesome. You don't need space elevators for motivation.
However it is not a given such a material is even possible. Bulk material strength is always far less that perfect theoretical strength. There has already been a paper suggesting that SWCN may not be up to the task due to "dislocations".
Also it may not be economical even if you have the material. The same material makes alternatives much cheaper too, such as plain old boring rockets. Or more exotic ideas such as launch loops or tethers.
Finally there is the problem with transit time. If you spend too long in the radiation belts, this is probably the last thing you would do..... A week sounds too slow.
Materials science 101 (Score:5, Informative)
No quotation marks needed. The problems in designing very strong materials have been known since WW2. The challenge can be expressed very simply: the more the strength depends on having a complete covalent structure (in CNTs the bonds have some ionic characteristic owing to the p-hybridisation but the same logic applies) , the greater the weakening effect of even a single fault. If a cosmic ray unzips a few bonds, the stresses will concentrate on the bonds on either side, and the split is likely to propagate. In strong metals we fix this with alloying components, very crudely like the gravel in concrete, which stop those dislocations from extending right through the material, but equally adding alloy components reduces the ultimately obtainable strength from a perfect structure. It is a tradeoff, as usual.
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The fact that we don't have the necessary structural materials yet to actually make a space elevator.
We have the materials, just not the means to produce them in the necessary quantities. I'm pretty sure the ancient Egyptians didn't have the necessary materials to build giant stone tombs either, but they built them so large that it took the rest of the world to build something bigger.
Neither Japan nor any Japanese company has the financial solvency to undertake such an effort
Well, if nobody wants to finance something so obviously profitable a few decades in the future then we really need to rethink our economic system, because at this rate, humanity isn't going anywhere in every sense of the word.
Re:Great concept except for .... (Score:5, Insightful)
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It'll have to be government subsidised. No corporation will do something that will pay off a few decades down the line their management has been trained almost to the point of reflex to get profits now because you might not be in business next quarter.
As a side note, the US's transco
Re:Great concept except for .... (Score:5, Insightful)
No no wants to spend a week in an elevator even if it means you get to go into orbit. Christ I can barely make it to the 15th floor without some jackass farting. A whole week. Don't think so.
To get from Vladivostok to Moscow on the train you would need 9 days. It used to take a couple of weeks or more. One train carriage carry approximately 30 people and the either share cabins with 3 other travellers or the whole carriage is one big cabin. People used to travel this way all the time before flying started to be an option. I suppose with our iPads etc the journey will be even less difficult
Re:Great concept except for .... (Score:5, Insightful)
No no wants to spend a week in an elevator even if it means you get to go into orbit.
Cargo doesn't care. One of the main attractions of a space elevator is that you can lift very heavy loads into space very cheaply and at little risk.
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No no wants to spend a week in an elevator even if it means you get to go into orbit.
Are you kidding? Where do I sign up? Besides which while it's an elevator in that it's pulled up a string, it most certainly won't be a 3m-cubed metal box.
Doors closing... doors closing (Score:2)
I agree with you. Nobody would want to be in an ordinary elevator for a week. I don't think anyone can be crammed into an ordinary elevator with 10 people in 2 m2, without food, drinks, seats/beds, for a week. Also, the lack of toilets in an ordinary elevator would be rather disturbing after a few hours.
So, this machine will hopefully be a little different than a regular elevator. Also, I hope it has a panorama window.
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English? (Score:5, Insightful)
WTF does that last sentence even mean?
Re:English? (Score:5, Informative)
WTF does that last sentence even mean?
It's just the editors being up to their usual standards of quality. The elevator cable doesn't end at the geostationary station (at 36000 km); it continues beyond it for another 60000 km, and terminates in a counterweight. This counterweight is supposed to be positioned 96 THOUSAND kilometers from the surface, hence the mention of the quarter of the distance to the moon.
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I'm pretty sure they were trying (and failing) to say the following:
It will take a week at 200 km/h for your party of 30 to reach the 36,000-km-high terminal station. Also, the elevator will need a counterweight at a height of 96,000 km, a quarter of the way to the Moon
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WTF does that last sentence even mean?
It means read TFA rather than the gibberish that the submitter, and Slashdot "editors" turn out. You'll find out, for instance, that:
"while the counterweight along 96 km high, a quarter of the way to the Moon"
should read:
"while the counterweight extends 96,000 km higher, a quarter of the way to the Moon"
Me gusta (Score:2)
I only now realize it says 96km. :/
Earth moon distance is 392937km. ChatHaunt said it best: http://science.slashdot.org/comments.pl?sid=2685249&cid=39121887 [slashdot.org]
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Once you hit distances that could best be described using Mm (like say 100,000km) you're probably best using fractions of AU.
! "world's tallest self-supporting tower " (Score:2)
submitter has it wrong. tfa states that it's ONE OF the tallest, with a meagre 600-odd meters.
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You realize those towers aren't self-supporting, right?
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Sorry wrong place in thread...
Is this technically possible right now? (Score:3)
I was under the impression that we didn't have materials with the tension strength to build a space elevator?
Re:Is this technically possible right now? (Score:4, Insightful)
These stories bring out a lot of clowns that think you can just throw stuff in the air and it won't come down, and reader, if you don't want to be seen as one of those clowns I suggest you look at the wikipedia page on these beanstalks then read and understand the very simple maths and physics before posting. A rotating frame of reference is a bit hard to get used to initially, so get your head around it before posting stuff that anybody with an engineering or physics background here will scoff at as magical thinking.
Tea, Earl Grey, hot. (Score:5, Funny)
It'll be a small matter of downloading the plans from an interweb and running the 3D printer overnight. A long weekend at most.
As for the financial aspects, bitcoin will solve all that.
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These stories bring out a lot of clowns that think you can just throw stuff in the air and it won't come down, and reader, if you don't want to be seen as one of those clowns I suggest you look at the wikipedia page on these beanstalks then read and understand the very simple maths and physics before posting
Actually, you can "you can just throw stuff in the air and it won't come down". That's what an "orbit" is. The beanstalk just connects the ground to the 24 hour orbit at 36000 km. The concept is simple and correct. The problem is making the beanstalk strong and light enough.
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We have laboratory samples of the needed materials. They are hard to grow, but are possible in theory.
Now, whether these materials will be PRACTICAL or not is another story. What will happen when they are subjected to constant tensile stress, enough stress to rip through nearly any known substance, 24/7 for a period of years and then decades?
Not well thought out (Score:4, Informative)
Furthermore, using the term 'elevator' is clearly an attempt to dumb-down the technology (kind of like called a Philosopher's Stone a 'Magic Stone').
Don't have a citation, but I believe that even using carbon nanotubes, the tether cable needs to be about 10 metres thick. This would mean that the project would require some 36 x 10 ^ 8 cubic metres of carbon nanotubes. Idaho Space Materials makes about 50gms per hour - at a cost measured in hundres of $ per gram.
I don't know that this is all practically do-able yet.
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Does anyone feel that this is a good concept? (Score:5, Interesting)
Look, ultimately you can't know if a technology is a good idea without actually building the tech, full scale, and spending the time and money to create revised versions to fix the major problems.
After you do that, some technologies are still a dog, no matter how you try to hide it. Nuclear power is an instance of that : sure it works, but the risk of catastrophe overshadows everything, and means that if you try to build and run a reactor everything costs too much because of the dangers. In the long run, nuclear is not feasible because other technologies will keep getting cheaper.
I feel a space elevator is a dog for a similar fundamental reason : there's one 36,000 km high structure.
Any serious failure to a manufacturing defect along 36,000 km of cable, and you lose every last dime invested in the project. (not to mention the falling cable might cause some nasty problems). If someone ever wants to attack a space elevator, it's a perfect terrorism target. One homemade cruise missile (in 2050, I suspect making a cruise missile won't be much harder than RC airplanes are today. Heck, some garage tinkerers already have done similar projects) and the ENTIRE elevator falls.
Not to mention laser fire, railgun fire, bad weather, etc etc. There's a lot of things and it only has to fail at one point.
Furthermore, you have to complete the elevator project before it is worth anything. Invest all that money to FINISH the cable, you can't get incremental results. And this multi-billion dollar structure (realistically probably hundreds of billions) has a rather limited cargo capacity : one load of passengers a week is NOT a rapid movement to space.
So, no. It's an idea that has somehow gained traction, but it is most likely a non-starter.
I propose a much simpler idea : rather than use lasers on the ground to transmit power to the elevator climber car, scale up those laser arrays a few orders of magnitude to the point that they can vaporize propellant off the bottom of the spacecraft. Pulse the beams right, and planar shockwaves will be created, giving net thrust without any kind of nozzle.
Advantages :
1. Ablative Laser propulsion doesn't require anything in the spacecraft in the way of aerospace hardware but a small instrument package to report attitude and accelerations back to the ground. Gyroscopes for stabilization would be nice, but not essential.
2. If a laser module on the ground fails or wears out, the launch continues..10 or 50% redundancy is entirely feasible.
3. You can do one launch every few minutes, assuming you use LED diode pumped fiber optic lasers, and have sufficient cooling capacity to remove the waste heat and sufficient power generation. That could be a metric ton or so to orbit every 15 minutes, 24/7, 7 days a week.
4. You do 1000 or 10,000 unmanned cargo launches before you send the first man up in a spacecraft identical to the one used for cargo (well, with life support inside, but identical flight hardware). This kind of sampling size allows you to honestly evaluate the safety of the system. In the event of a problem, you turn the beam off instantly and deploy parachutes. (such as beam heating of the side walls or something). No rocket to explode.
5. Each spacecraft will be extremely cheap, just a block of an inert solid bolted to the bottom, and a small instrument package (an iphone has all the circuitry needed, although of course you would use more sensitive accelerometers) and a radio. Obviously, some kind of orbital maneuvering system is also needed, but you can get to orbit without it.
Disadvantages :
1. Reflected beams from the lasers might cause problems for observers on the ground. Might have to create a large exclusion zone around the launch site, with air travel forbidden in a large radius. Not a big deal, tons of places in the Arizona desert. Still, with so many people involved, it seems likely a few people would be blinded if the lasers used were visible light.
2. It would r
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Why a cruise missile? I think a small remote-controlled toy plane with a little bit of explosive on it would probably suffice. Remote control might be via satellite internet.
Re:Does anyone feel that this is a good concept? (Score:4, Insightful)
Fair enough. Basically, the cable is always going to be stressed to a large percentage of maximum loading. It will also be made of carbon, which is flammable. I suspect that many kinds of weaponry could cause just enough damage to cause it to unravel and fail in short order. An incendiary charge placed against the side of the cable with a swarm of R/C helicopters might work just as well.
In any case, it's the ultimate in single point failure. Yes, you can attempt to secure the cable with missile defenses and other weaponry, as well as elaborate security checks of everyone allowed near it. I just can't see such an effort working when it's so trivial to actually destroy the cable, however.
Even a few 20mm rifle rounds in the same spot might be all it takes.
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A few corrections.
1. The cable is permanently stretched by a counterweight at the 96000 km altitude. If you sever the cable 1 km from the surface, the bottom 1 km falls to the ground, the top 95999 km fly away and settle in an orbit around the Earth.
2. If you can manage to build a 96000 km cable, it should be trivial in comparison to build a protective sheath in the form of a 10-foot-thick concrete chimney surrounding the base of the cable up to the elevation of 5 km or so. That takes care of R/C helicopter
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Actually nuclear has a much better shot. With new designs including pebble bed, silicon carbide fuel elements and helium cooled reactors, and the advent of tiny sealed reactors (everything is in a small sealed package so there's nothing to run out of, nothing to fail critically, a complete self contained reactor.) Nuclear has never looked brighter.
On the other hand, so far nobody has even mentions this thing will be sticking outside of the protection of earth magnetosphere out into the solar wind. Massive c
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Many of your points have been debunked years ago, especially the falling cable problem. Please, try harder.
More Detailed Article. . . (Score:5, Informative)
. . . is located here [mainichi.jp]. It includes a bit more about the proposed construction, starting date, and other interesting bits.
Passage to geosynchronous orbit (Score:2)
Wrecking Skylines? (Score:5, Informative)
Really? With the train station in Kyoto? Seriously? I've been there, both in the train station and in the surrounding area. It's big, but it's not exactly skyline wrecking unless you happen to live in an apartment which directly faces it. There are plenty of other buildings nearby which are close to the same height and once you get about two blocks away, you can't even see it from the street. If you don't believe me, here's a picture [obayashi.co.jp] from above which shows the surrounding area. Plenty of other 8+ story buildings in the area. Here's a view [tripadvisor.com] from the top of the hotel in the train station. What skyline is it that they're destroying exactly?
Kyoto is a lovely city. It has myriad beautiful temples and gardens and the nearby country-side is lovely. People flock to it to see the cherry trees when they are in bloom. But none of these things are very tall. Most of the famous temples aren't even visible when you're half a block away from them, nevermind part of the skyline. It does not now have an impressive skyline and if it ever did, it must have been centuries ago, and although the train station big enough to be clearly visible for a couple of blocks around, it's not exactly a sky-scraper. Honestly, its width and shininess stand out as much as its height. So, if the person writing the article thinks that the Kyoto train station (which has far more non-shinkansen platforms than shinkansen platforms) is too big or too shiny, then fine, but saying that it wrecks the skyline is just dumb.
Not a chance in hell. (Score:2, Insightful)
Without substantial advancements in material research, this cannot happen. No current or upcoming material exists that can withstand the extreme shear forces that would be exerted on a space elevator.
Space elevators are currently the realm of science fiction, and will likely remain so even in 2050. If we had the technology and materials to build it right now, a 2050 completion would still be unlikely. And we have neither the tech nor the materials.
Where will they build it? (Score:4, Interesting)
Re:Where will they build it? (Score:4, Funny)
Oh come on, you're making at least some of those names up. I've been as far south as Tuskegee and I've never heard of any of those places.
Fire escape stairway (Score:5, Funny)
Clearly more aspirational (Score:2)
I applaud them for exploring the possibilities. The only thing I would question is whether carbon nanotubes are strong enough? No one has been able to make them in quantity but my understanding was that even if you made it out of complete strands of carbon nanotubes... that is if you had monomolecular strands of the stuff stretching from geo sync orbit to the ground it wouldn't be strong enough to take the stress. I have in no way done the calculations on that and have no links to back up that statement. Bu
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it's a strength to weight ratio issue isn't it? What's stronger... 100 feet of steel cable or 100 foot long structure of equal weight made of steel?
A cable made of dental floss would snap under it's own weight after much less then a mile. Steel... again with only it's own weight to support probably wouldn't go more then a mile. Lets say optimistically that this special nano molecular cable can reach 20 miles before snapping under it's own weight... it has to reach a hell of a lot farther then that.
I'm not c
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Build it from the counterweight asteroid placed in geostationary orbit, building down towards its socket on the planetary surface.
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Elementary!
(We'll just use our well proven asteroid manufacturing plants. After we park an asteroid in orbit the way we always do. By 2050.)
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Hell, all we need to do is figure out how to do it, then "leak" the info to the Chinese, and they'll do it twice as fast at 1/8th the cost. Plus, their overworked asteroid miners won't be able to jump to their deaths in near-zero G!
Re:How to install it? (Score:4, Informative)
It's a cool idea but requires a material that does not exist yet fabricated to lengths not yet possible while requiring techniques to get things up the beanstalk that have not yet been developed. However carbon nanotubes, if they prove to be strong enough, are highly conductive so the power for a climber may be able to be delivered from the ground without any weird laser or microwave wireless power advances required.
Anyway, just ignore the "possible now" or "indian rope trick" freaks and enjoy the cool newtonian physics thought experiment while hoping this doesn't create too many scams on the fringes.
Just treat it like cool SF with some real world constraints and a minor bit of handwaving to ignore a few of the more inconvenient real world constaints. Such a massive (pun intended) project needs to be just a tiny fraction of the mass intended to be moved beyond geostationary orbit for it to be worth doing instead of just using rockets. The "indian rope trick" fanboys in paticular forget that a hell of a lot of mass has to be moved up there by rockets in the first place just to get started. Unless we are lucky enough for a relatively small asteroid to sit for long enough at a lagrange point for us to catch it and slow it down enough for it to be used as a counterweight then truly vast amounts of mass have to be accelerated to very high velocities to build a beanstalk. Even with the captive asteroid option that's still ludicrous amounts of fuel to get it to where it can be used.
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See my post. From day 1, another way looks like it is a LOT cheaper and easier, both per launch and overall. Google for "ablative laser propulsion" : like a space elevator, but with more lasers, and no cable.
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I hate to break it to you, but 50-12 is frequently 38, not 28.
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+1 For beating me to it.
Answer: Alert sickbay to prepare to receive all crew members aboard the elevator.
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An object above the earths equator and stationary with respect to the earth has an effective weight of (actual weight)-(centrifugal force). As distance increases weight decreases and centrifugal force increases. At the height we call "geostationary orbit" the effective weight is zero (hence why something can remain stationary relative to the earth at that altitude without a tether). Beyond that height the effective weight is negative.
So assuming a space elavator is defined as "a cable leading into space sup
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> Wake me up when they have space stairs.
"NO Stairway to Heaven!" This is your only warning. :)