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Japanese Begin Working On Space Elevator
thebryce writes "From cyborg housemaids and waterpowered cars to dog translators and rocket boots, Japanese boffins have racked up plenty of near-misses in the quest to turn science fiction into reality. Now the finest scientific minds of Japan are devoting themselves to cracking the greatest sci-fi vision of all: the space elevator. Man has so far conquered space by painfully and inefficiently blasting himself out of the atmosphere but the 21st century should bring a more leisurely ride to the final frontier. Japan is increasingly confident that its sprawling academic and industrial base can solve those issues, and has even put the astonishingly low price tag of a trillion yen (£5 billion) on building the elevator. Japan is renowned as a global leader in the precision engineering and high-quality material production without which the idea could never be possible."
Just imagine fourteen hours of Japanese elevator music. I couldn't stand that much symphonic David Hasselhoff. And when you get to space and arrive at the Japanese Sky Deck, you can eat very expensive steak, while being entertained by a Max Headroom stylized recreation of David Hasselhoff, and groped by Hentai-motivated space-whores.
The dangers of knowledge trigger emotional distress in human beings.
$9 Billion Here, $9 Billion there -- pretty soon we'll start talking about real money.
They're going to use Mothra for the lift engine of the elevators.
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
The concept of a space elevator, of course, requires a very very tall structure, or a pully of sorts from space. That would need to be a really damn strong system, to pull somebody up that high...
Yes, you instantly recognized the challenges of the project. Please, come, be a manager on the project!
Red Leader Standing By!
"The first space elevator will be built about fify years after everyone stops laughing."
-Arthur C. Clarke
The meek may inherit the earth, but the strong shall take the stars.
Nor did you RTFWikipedia. It's a held up by a weight at geosynchronous orbit. The only problem is that geosynchronous orbit is so far out there (the red dotted line is the International Space Station, the black dotted line is GEO), so it requires a WHOLE LOT of exotic material.
Absent any stunning advances in material sciences,
The TFA states that carbon nanotubes would require a 4x increase in strength compared to present-day materials, and that the past 5 years of research have already brought about a 100-fold improvement ... sounds to me like many stunning advances have already happened and we're well on track to fully-stunned status.
This is just a Popular Science article, i.e. "hey wouldn't it be neat if but it ain't happening so we're really just jerking your chain."
"Japan is hosting an international conference in November to draw up a timetable for the machine."
If libertarians are so opposed to effective government, why don't they all move to Somalia?
That's probably not how it would be done. You'd have a ribbon hanging down from geostationary to the equator, and your vehicle would actively climb up it, rather than being hauled up. The ribbon still needs to be incredibly strong and light, but it's not the component that's actually doing the work.
Exercise for the reader: work out how you're going to power the climber.
Real Daleks don't climb stairs - they level the building.
And as a sub-subnote, this is approximately the cost of developing a complete conventional man-rated rocket launch system. I'm skeptical of the quoted price tag, but it would be extremely cheap if it could be achieved.
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You have an anchor at the top of the ribbon. It needs to be very massive compared to the payload - so we need a large space station, or a small captured asteroid. You have it in an orbit that's slightly above geostationary, so that it tends to drift into a higher orbit and is kept in place by tension in the ribbon. That way, the top is pulling upwards naturally, and the payload doesn't drag the whole structure down.
Real Daleks don't climb stairs - they level the building.
A practical space elevator could use vehicles powered by electric motors, which would get about 70-80% efficiency. On the way down, the motors could be used as generators, getting back probably around 30-50% of the original energy supplied. The total energy consumption might only be a percent or so of that needed for a rocket. The design of the cable with electrical conductors on either side reaching all the way up to geostationary orbit is, of course, left as an exercise to the reader.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Well, no. Modern materials are within a factor of 3 or so of what's required for a space elevator, and known materials with sufficient theoretical strength exist, it just needs to be figured out how to build them. It would not be surprising to have those materials move from theory to reality within a decade or so.
AI, human-indistinguishable androids, and world peace, on the other hand, are not things that people have any idea how to achieve. And FTL drives are prohibited by currently accepted physical theory. To compare a space elevator to any of those is either deliberately being stupid, or a result of profound ignorance about either space elevators or all the other things you mentioned.
A space elevator is certainly not going to be as easy as a Popular Science article makes it sound. But on the other hand it's not anywhere near as difficult as the pipe dreams you named.
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...No space elevator is going anywhere without the necessary nanotube manufacturing breakthrough, and that includes the Japanese.
Exercise for the reader: work out how you're going to power the climber.
CowboyNeal as a counterweight?
They just saw that the EU completed the LHC world wonder so they are building a Space Elevator wonder to prevent a cultural victory.
I'm always afraid of getting stuck halfway up on a space elevator (one bustle in your hedgerow and the whole thing gets jammed up). I'll just take a Stairway to Heaven, there's a lady I've heard good things about that is buying one.
would that work to finance the japanes space elevator:
1- take a subprime loan from a US bank
2- file for banckruptcy
3- let US treasury buy the debt back and cancel it
4- Profit !
I mean with that they could spend as much as 700 billions !
If I find a golden ticket in my package of ramen noodles, do I get to ride the space elevator?
I got an email earlier today guaranteeing a gain of 1-3 inches in length. It's a start.
You're thinking of making a big tower (like a really large skyscraper). That wouldn't work. You have to approach the problem differently.
A simplified explanation of a space elevator is to take a really long, really strong cable (nanotubes), hang a weight on the end (more cable, an asteroid, lots of metal, etc), and anchor it on the equator. The weight goes out beyond geostationary orbit, and the tension of your cable pulls in on the counterweight to keep it from flying away. The tension keeps your cable taut. You can then run "cars" or "trains" up and down the cable on motorized wheels, most likely with electric power (solar, beamed microwave, or conducted through the cable). Your car can travel nice and slow, and be more efficient than a rocket.
If this doesn't make sense, imagine tying a weight to the end of a string, holding on to the other end, and spinning in circles. The weight will be held out at the end of the string and appear stationary relative to (since you're spinning too). Now put a caterpillar on that string that walks to the counterweight and back to you.
In short, the advantage is that you can use electrical power (which you don't have to carry with you) converted to direct mechanical energy to climb into orbit, instead of expelling fuel (less efficient) that you do have to carry with you. Your vehicle ("car") structure is simpler, more robust, and cheaper than a rocket. The elevator itself would be quite expensive, and requires some advances in materials science, but isn't physically impossible.
The meek may inherit the earth, but the strong shall take the stars.
The elevators traveling speed will be measured in GFIp/t ("Girl from Ipanema" plays per transport).
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actually it's the center of mass that is relevant. The device would be considered in GSO because the center of mass would be there, or minimally lower (a few feet).
There would be roughly evenly distributed mass from earth to GSO, Maybe slightly increasing as it goes up to GSO, and then a large weight beyond GSO.
The idea is to not have it pull up on the ground, or press down (much). Last thing they need is to have a huge chunk of the terminal flung into space.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
In other words, their "space elevator" will probably more closely resember a sleeker rocket/airplane design, and less like an actual elevator...
Given the speed you'll want to haul cargos up to have them there in a reasonable time you'll want some areodynamics.
Even assuming you speed up once you reach upper atmosphere/vacuum, a 22k mile journey at an average speed of 100mph will take 220 hours, or just over 9 days.
I'd see a fuel cell system for in atmosphere lifting, shifting to battery/solar once you're over the atmosphere. Maybe even jettison the fuel cell to be recovered and reused.
Though there is a chance you could use the cable - electrical potential is generated if you string a conductive line through a chunk of the atmosphere, and CF is conductive. You still have the problem of how to utilize that differential at any given point of the cable though. You might end up using a double ribbon system and shipping electricity that way to the cars.
I don't read AC A human right
Those sound like elements to factor into the design, rather than unforseeable or unpreventable disasters.
Can we please not use the word "Boffin" to describe scientists. Its a words used by the British tabloids, usually out of ignorance, and in a derogatory sense.
And as a sub-subnote, this is approximately the cost of developing a complete conventional man-rated rocket launch system. I'm skeptical of the quoted price tag, but it would be extremely cheap if it could be achieved.
That's not the actual price-tag, it's NIF economics. You propose the project with a $9.5B price tag and spend your money providing whatever results you can. You then apologize for failing to complete, but assure the backers that you're nearly done, but need an additional $5B. When that's spent, you've hit a snag so complex that not even the top minds in the world could have seen it coming, but you can finish the project for only $8B more. After all, who wants to abandon a project that you've already spent several years and nearly $15B on when you're so close. Repeat until retirement.
It's amazing how well this seems to work in practice.
He's getting rather old, but he's a good mouse.
A space elevator essentially just needs certain advances in materials science. It's a big engineering project, but nothing more than that.
AI, on the other hand, is something that nobody in the world has any clue how to achieve. They're simply not comparable. We may very well see AI before a space elevator, but it will be because computer technology advances vastly more quickly than space technology.
And just for the record, I did not claim that FTL is impossible, merely that it's impossible according to accepted physical theory. And that statement is absolutely true.
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So for the price of what Wall street caused US government to pay, you could get a space elevator for each country in the world (almost - the smallest ones will have to share ofcourse)
.ACMD setaloiv siht gnidaeR
I have the solution though. To get around the problem with the long cable and pulley, we can use rocket propulsion on the bottom of the elevator cart.
Also since the shaft it will travel may encouter some problems with radial velocity and all that engineery stuff I know barely enough to be dangerous about, we should cut that out and just create a cart that doesn't need that.
Yeah, a rocket propelled shaftless space elevator. Where's my damn X-prize or whatever money for being so smart....
-- A computer without COBOL and Fortran is like a piece of chocolate cake without ketchup and mustard
Good thing you're anonymous. If I had a 'nanotube' I sure wouldn't want to admit it on slashdot. :)
Actually, it would take a guy in the spacecraft a minimum of 4.3 years to arrive at Alpha Centauri. In Earth's reference frame it might take thousands of years. I'm saying that you're using the times in the wrong frames of reference.
How disappointing would that be? You get yourself all packed up and ready to go to Alpha Centauri. You're excited, the kids are excited, you're going to be the first humans to ever step foot outside the solar system. It's groundbreaking stuff, you are lauded as heroes as you step into your state-of-the art ship that travels at 60% of the speed of light.
After almost ten difficult years in a cramped interstellar ship, you and the other colonists can finally see your destination. You will forever own a place in the chronicles of human history. And then, you discover than the place was already colonized by humans centuries ago ... the ones who waited until FTL travel was invented back on Earth. They made the trip in a couple weeks. They've been waiting for you ever since.
If libertarians are so opposed to effective government, why don't they all move to Somalia?
So don't tie it down. There's nothing about the design of the space elevator that requires it to be tied to the earth in any way. If there's a storm coming, pull it up (or fold it up) about a mile or so above the clouds.
"Japanese Begin Working On Space Elevator"
Did that headline make anyone else feel like we're in one big game of "Civilization"?
The problem is that even the *simplest* form is way beyond what we can produce in the present day, and you're wanting to do a form that's far harder.
In a space elevator, the tether has to be long. Very, very, very long. So much that even if you could build a cable with the density of graphite and a tensile strength of 100GPa, it'd still have to taper severalfold as it reaches toward the earth. With the taper requirement, pulleys are simply right out (can't have the pulley's cable change shape as it goes, now can you?), as is *anything* that can increase the weight of the fiber. You need elevator "climbers", powered by beamed power transmission.
The problem remains the cable. 100GPa with the density of graphite is just so far beyond anything that we can achieve today it's really just a sci-fi concept that people like to dream about. The last I checked, the strongest *individual single-walled carbon nanotubes* that people had directly measured the strength of broke at just over 60GPa. This is for single tubes, let alone bundles of tubes, let alone a bulk fiber, let alone an entire tapered cable. Tubes theoretically can be stronger, but I haven't seen any measurements confirming such extreme theoretical strengths. The strongest SWNT bulk fiber I've read about was planar sheets that were about 10GPa.
Yes, you can build a space elevator with a tensile strength of less than 100GPa. But your taper factor for the elevator rises *very fast* with decreasing tensile strength or increasing density, which means that its mass increases *very fast*, which rapidly puts it outside the realm of possibility. Honestly, something more like 120GPa would be much easier to build, but that's even further from what we can achieve today. I'm not even sure it's physically possible to achieve. SWNTs are pure graphene SP2 structures; how can you get stronger than that? The only thing I can think of that could help us best today's best strengths are complete perfection, every atom of the fiber all the way up, and I'm not sure that would do it.
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