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Obayashi To Build Space Elevator By 2050
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."
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.
It probably won't hurt your corporate image too much to bolster some idealism every once in a while.
I was the real korpiq until I woke up clowned.
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.
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.
Trying to become famous by taking photos. Visit my homepage please.
1. The fact that we don't have the necessary structural materials yet to actually make a space elevator.
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.
----- In Your Cubicle No One Can Hear You Scream...
WTF does that last sentence even mean?
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...
"There is more worth loving than we have strength to love." - Brian Jay Stanley
I was under the impression that we didn't have materials with the tension strength to build a space elevator?
I swear to God...I swear to God! That is NOT how you treat your human!
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..
Whilst geosynchronous orbit is achieved at about 36,000 Kms, the atmosphere ends at roughly 120kms. Using some kind of rail to continue to elevate the payload will be hideously inefficient outside the atmosphere.
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.
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
. . . is located here. It includes a bit more about the proposed construction, starting date, and other interesting bits.
My sister opened a computer store in Hawaii. She sells C shells by the seashore.
The sanest proposal I've seen is to send a "string" of it up on a reel into geostationary orbit and unwind it outwards and inwards with a highly controlled descent under tension for the portion that descends to earth. I suppose from then the plan is to attach other fibres and move them up in some way until it is strong enough to take full loads.
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.
Nope, this one.
https://www.youtube.com/watch?v=i1EG-MKy4so
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.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Great destination! The view never changes! Sun rises and sets once per day; just like home!
Their they're doing there hair.
I'll be in my early 70's, hopefully still alive...
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 from above which shows the surrounding area. Plenty of other 8+ story buildings in the area. Here's a view 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.
I hate to break it to you, but 50-12 is frequently 38, not 28.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
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.
My understanding is that it will have to be the equator, which gives them a choice of Ecuador, Colombia, Brazil, Sao Tome & Principe, Gabon, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya, Somalia, Maldives, Indonesia and Kiribati. Or maybe they're going to build an artificial island and port, I would imagine that's child's play compared to the elevator itself.
Imagine the fire escape. How long will it take to walk up/down in a space suit?
Excuse me, but please get off my Pennisetum Clandestinum, eh!
No, you. The 96km is a mistake in the summary. The number in the article is 96,000km.
They are 117 times stronger than steel according to this:
http://www.sciencedaily.com/releases/2010/09/100915140334.htm
My maths and physics are a bit wonky, but I doubt whether you could build a steel cable 300 km long that could support move it's own mass even in zero G. I think they need another order of magnitude or two for that.
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 claiming to be an expert... I'm just a curious novice in these matters. But the strength issue seems to be far short of the requirements.
Still... it's an interesting program even if we have to use "unobtainium" to build the cable.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
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.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
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.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
214 comments and no one's mentioned Arthur C. Clarke yet?!
Someone on Slashdot must have read Fountains of Paradise, surely...
The power of accurate observation is commonly called cynicism by those who have not got it. -- G.B. Shaw
> Wake me up when they have space stairs.
"NO Stairway to Heaven!" This is your only warning. :)
"Slow down, Cowboy! It has been 3 years, 7 months and 26 days since you last successfully posted a comment."
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.