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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
A trillion yen is about 9.5 billion USD or roughly 6.5 billion Euros. That sounds like a bargin to me.
Dedicated Cthulhu Cultist since 4523 BC.
Absent any stunning advances in material sciences, the space elevator is still in pipe dream territory along with FTL drives, AI, androids indistinguishable from people, and world peace.
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."
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I can't tell you how many times I've needed one of those.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
1.) Every action has an equal and opposite reaction.
2.) Metal is stronger when being pulled then pushed.
3.) If we make a space elevator, the elevator will need to move vertically, which will cause downward force. This will either be absorbed by the bottom (very unlikely), the top (Seems possible, but improbable since the top will need fuel to pull the item upward), or using boosters (not very different from the current method).
Is there an advantage that I am not seeing? Every method requires fuel unless all of the weight is absorbed by the bottom, which is unlikely if they use metal.
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!
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"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.
The Japanese just want to be the first to build a ladder to Heaven.
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.
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.
My only knowledge of space elevators is probably what I've read on Slashdot and the occasional pop article, so for now it seems like a pipe dream - however, its a pipe dream that seems likely to come true at some point. Most articles fail to get passed the concept however, so I have some questions:
:)
lampsie
1) How would one get the opposite end of the "tether" into space after its been bolted to the Earth?
2) What kind of payloads are the likely going to be capable of carrying?
3) Will the tether and the space-end of the tether need regular augmentations? (e.g. alignment, raising, maintenance etc)
Thanks
Elon Musk throws a chair at his Sony flat-screen TV upon hearing the news.
Send your spendthrift head of state this
maintaining geosynchronous orbit while tethered to the ground is not a good idea. there are so many factors that could turn a space elevator into a complete disaster. a cat-4 or 5 hurricane could potentially put so much drag onto the cable that the whole thing tumbles to earth. an earthquake could yank it out of orbit. tidal pulls from the moon could rip it from the ground. lightning damage. i'd love to see this become a reality, but i just dont think that will happen.
FOXTROT UNIFORM CHARLIE KILO
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."
Technically, a weight in geosynchronous orbit would remain at the same altitude indefinitely with no other forces in effect. A space elevator will require a weight placed in an orbit which will supply tension — otherwise it'd be pulled out of orbit. It would probably be close to geosynchronous, but not quite.
(Actually, I'm not sure we even have a name for such an orbit. It would have to remain stationary above a point on the earth, but it would also have to hold up the cable and the car – in other words, without the tether it'd fly off into an entirely different orbit. Also, whenever the car accelerates it will put an additional tug on the cable – equal and opposite forces, you know. It'll be a tidy little equilibrium problem, and I'm glad I don't have to solve it!)
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
...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?
Technically, a weight in geosynchronous orbit would remain at the same altitude indefinitely with no other forces in effect. A space elevator will require a weight placed in an orbit which will supply tension â" otherwise it'd be pulled out of orbit. It would probably be close to geosynchronous, but not quite.
Couldn' this be achieved by moving a counter-weight downwards from space while the elevator moves up?
The total force on the weight in orbit would remain constant wouldn't it?
This was an idea that I had a very long tie ago when I was still a teenager (before I had ever heard of space elevators). Lets imagine you had a geostationary satellite in orbit above your construction site. That satellite then lowers a cable into the atmosphere (due to it being geostationary there should be minimal re-entry friction) your main concern would be dealing with the winds on a 100km long cable dangling in the air. Once you have connected the cable to the land, fire some booster rockets on the satellite to get it into the desired orbit (say L1), you could even have the shuttle attach some larger equipment to it to increase it's mass.
With an increase in mass and the longer distance from the planet, centrifugal force should keep the cable taut. You now can start having things 'climb' the cable to build a larger platform.
Why wouldn't this work?
"The price good men pay for indifference to public affairs is to be ruled by evil men." ~Plato (427-347 BC)
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.
If I find a golden ticket in my package of ramen noodles, do I get to ride the space elevator?
The elevators traveling speed will be measured in GFIp/t ("Girl from Ipanema" plays per transport).
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Greatest, in terms of biggest, would have to be a Dyson sphere. I see the Japanese haven't started on THAT one yet.
I piss off bigots.
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
I don't know but at least getting rescued is an option. I prefer the 'stuck in elevator' failure mode to 'fiery death' that current rockets offer.
"Physics is to math as sex is to masturbation." -R. Feynman
That's even worse, damn it. I can't stand it when people directly copy something and then act like it's a paraphrase. If it's a direct copy, it needs to be clearly quoted and sourced. If it's not in quotes or set out in a blockquote, you shouldn't be using the exact wording given (except in the rare case that it's so short that it's relatively impossible to paraphrase). If you don't put it in quotes, blockquotes, or paraphrase it, you're plagiarizing (even if you've linked to the source).
Yeah, I'm pedantic at times. This pet peeve, however, is something I feel justified in detesting.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
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.
Sir Arthur C. Clarke, when asked about when the space elevator would be constructed, he said something like:
Probably about 50 years after everybody quits laughing.
link.
Don't shut the idea, the idea is pretty good, yet the implementation is going to be tricky, with a space elevator, sending a kg. into space will be way more cheap than what is cost nonadays.
DON'T PANIC.
The cross-Britain maglev (16 billion pounds, http://en.wikipedia.org/wiki/Transport_in_Glasgow#Future_Plans) is estimated at approximately twice the price of mankind's rope into space.
It'd probably be relatively easy to design such a system if it didn't move. However, the car ruins the Statics solution and you then have a dynamic problem... you've got acceleration (which means a varying force on the anchor), you've got a COG that isn't stationary, the second moment isn't constant, and it's a lot more difficult.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
Doesn't matter really. Power it from the ground; then you can feed the energy generated from it coming back down back into the system. Wouldn't be a net gain, obviously, but it would reduce the power requirements substantially.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
Supposed you were to get stuck near the very top in space? Who is going to come and rescue you? Ultra-Man? Optimus Prime? Godzilla?
Don't be stupid. Godzilla never went to space.
converted to USD instead.
Well...
Slashdot is run by Americans, after all, and the vast majority of our readership is in the U.S.
Not that you'd ever want to do things just to benefit the vast majority of your readership, but it's an idea.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
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
You mean the thing that orbits Earth?
So we'll eventually have cable wrapped around our planet like a rubber band ball?
And the moon will collide with Earth?
The best counterweight is... another elevator car. If you have multiple tethers and superconducting cable (or another means of transmission), you can use a large fraction of the potential energy of the descending car to power the ascending car.
If you bring net mass down from orbit, you can actually make an energy profit (just on the elevator, I'm not saying that it would offset the costs of hauling propellant, etc, for asteroid miners and such).
If you bring net mass down from orbit, you can actually make an energy profit (just on the elevator, I'm not saying that it would offset the costs of hauling propellant, etc, for asteroid miners and such).
Yeah of course you can't win overall, but nevertheless wouldn't it be totally awesome to bring back a load of minerals from an asteroid and get a "free" lift of your next load of fuel and supplies?
The enemies of Democracy are
As always:
http://en.wikipedia.org/wiki/A_Ladder_to_Heaven
The "Tower of Babel" project was abandoned before they installed the bell on top.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
WOOSH!
There it went.
Sweet informative mod.
As I understand it the popular plan is to not actually attach the bottom end - you have it float around at fairly low altitude over the middle of the Pacific and reach it by conventional aeroplane - at least for the first one, perhaps when the technology's tested we can think about having one with train lines running there. Anyway, with such a "floating" elevator there's no need for absolute precision - if it moves a few tens of meters who cares. Just stick some thrusters on it so that it can be actively stabilized.
I am trolling
You're mostly right. A weight in geosync with a tether hanging down would fall, due to the weight of the tether. What you actually have is a system where the center of mass of the entire system is in geosynchronous orbit. There are two ways you can do this, one is to have a big chunk of mass just the other side of the orbit you want, the other is to have another tether extending outward from the geosynchronous midpoint. There are some advantages to that idea. If you want to go somewhere further than earth orbit, you can go out to the end of the outer tether and start off with a fairly healthy velocity, although constrained to being in the plane of the equator. (although, given that the plane of the equator varies considerably with respect to the plane of the ecliptic over the course of the year, you actually have a fair amount of, well, latitude for lack of a better term, with your initial vector if you have the ability to move around your launch date some.) Second, it makes it fairly easy to run masses up and down the external tether to counteract the mass/acceleration of the elevator on the inner tether. Third, if you for some reason want an environment with near-earth-normal gravity, but want it to be 70k km (that's an ugly nomenclature. and 70 Mm looks too much like 70 mm. How about 7E7 m?) away from the earth, there's a perfect place for it, just hang your lab off the end of the outer tether.
The disadvantage, of course, is that you have to make two long, expensive tethers, as opposed to making one tether and a big block of steel (or whatever) as a counterweight.
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A space elevator is hardly the greatest sci-fi vision of all. The greatest sci-fi vision of all (aside from higher ratings for the SciFi Channel allowing them to produce more original features) is faster than light interstellar travel. A space elevator to nowhere pales compared to that.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Except that you're wrong. It's expected to be a flat ribbon rather than a round cable - despite the mass, most of the thing will float down like shreds of paper if it's destroyed, the heaviest pieces of which will burn up in the atmosphere long before they reach the ground.
The best way to build a space elevator would be to begin at GSO and build outwards from there, keeping equal mass towards and away from Earth. You can then maintain a stable CoG by having masses at the top and bottom of the elevator structure that can be added or removed as needed. Note that in this design, the elevator is NOT tethered to the ground and is in fact in orbit with a portion coming near the ground. Some form of thrust, likely ionized gas propulsion, would be needed at the top to counteract drag and other wind acting on the lower section of the elevator.
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Gee, let's hope that a war over the elevator doesn't break out, causing a young pilot to detonate the Space/Time Oscillation Bomb and splitting time/space into lots of little pieces.
"Japanese Begin Working On Space Elevator"
Did that headline make anyone else feel like we're in one big game of "Civilization"?
He left out the base assumption there, that everyone leaves out.
Once you pay for the space elevator, the incremental cost for sending a KG of cargo into space is cheap.
This is the same statement, less clearly made, as the comment somewhere above here that talks about costs of a space shuttle flight. It says, looking at total program costs, the space shuttle costs $1.3 billion per flight as of 2006, but looking at incremental costs, it is only $60 million per flight.
The unobtanium is, of course, part of the initial cost, and which most people on here seem to think is underestimated in the Japanese announcement.
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NASA with the the Italian Space Program tried long (up to 5 km) space tethers several times. Either cable fries and breaks from huge electrostatic charge breakup or the satellite fries. Anyone whose flown a kite with a metal wire knows the problem is even worse in the atmosphere.
I have always hated the idea of GEO to Earth space cables. A "flying" space cable would be much more efficient, is possible with current technology, and would be able to provide service to much of the earth. Just think of 4,000 km cable with it's lower end just above the atmosphere(100km-150km up). The bottom end is traveling at less than orbital velocity for it's elevation and the top end is traveling at more than orbital velocity for it's elevation. This could reduce launch costs so that sub orbital launch vehicles could reach the lower end from most major international airports. Think of it as a vertical Panama Canal to space.
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.
You don't exist. Go away.
Well, that's just as well, because I _don't_ want the androids to be indistinguishable from people. When somebody builds that hot android maid, well, if she's just real people, she'll tell me to get lost and she'll go marry a jock. Or pretend to like me only as long as I clean spyware off her computer, then go write online prose with it about how nerdy, self-proclaimed Nice Guys are, like, so yuck, and how sexist of them it is to put you on a pedestal.
I don't want _that_. I want an android nobody can possibly confuse with the real thing. I want her to be more like, "mmm, I find your milky-white manboobs soo sexy. Lemme fix you dinner, then we'll fuck like crazy rabbits, and then we'll go farm those feathers on WoW together. Won't that be romantic?"
(Ok, ok, I know that's very sexist and all, but it's all for a greater cause: comedy. That's how selfless a guy I am;)
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You obviously have no idea of the margins on the weight problems in this project. How much would a cable (capable of transmitting enough voltage) weight? The whole 35 000 kilometers of it? At such length even steel can not support its own weight, the weight of any type of additional conducting material on the ribbon will likely double or even tripple its weight and that in turn doubles or tripples the ammount of force the ribbon must be able to carry (per unit of weight). Currently we are struggling to get from current 10 GPa to the required 100 GPa and you propose to go up to 300 GPa just to get a cable up?
Laser power transmission to send energy from a ground-based nuclear power plant to the climber is a well tested solution that will not increase the weight of the system. Read up on the state of art before throwing absurd suggestions, please.
First I didn't quite understand the wording of your post, it almost made it seem that Raygun was talking TODAY
First, He's a former US president. A deceased former US president. Show some respect please. Second, I was refering to a speech he made while president, when he first proposed the SDI program.
A complete SDI system is what Reagan wanted; a comprehensive STRATEGIC (not tactical) defense system that could rid the world (actually just us) of nuclear terror.
Yes, the mission statement has changed a bit.
BRUTE FORCE OVERWHELMING the system with THOUSANDS OF WARHEADS
Oh, I agree. For that matter even before Reagan proposed SDI the USSR had enough nukes to overwhelm us. The idea was to make it more expensive to do so. In the course of time, though, Russia has ceased to be the primary threat; now we're worrying about 'rougue nations' with less than a dozen missiles. So we can save a lot of money by not trying to protect against the thousands of nukes Russia can still launch.
I don't read AC A human right
You know, if we just increased the spin of Earth, we wouldn't need as long of a cable to get to GEO.
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At a distance of (iirc) about 2/3rds of the way to geosynchronous orbit, an object dropped off the elevator will be in an elliptical orbit that just barely misses the atmosphere. Anything lower than that will re-enter. With rockets, of course, you could drop things lower and/or achieve round orbits.
Launching from beyond geosynchronous orbit ultimately robs the earth of its rotational energy (something that happens all the time anyways because of tides), so that's not really a big deal for the elevator as long as it can handle the additional tension. It would be a great way to launch things towards the rest of the solar system without wasting fuel.
I'm sorry, what about being president is implicitly worthy of respect?
We're talking about the man who singlehandedly tripled the debt, doubled spending, and sent the Republicans down the path they're on today of insane leftist spending.
I'll respect him the day I respect the idiots at AIG.
It's been a long time.
This is an interesting observation I happen to agree with. What's interesting is that Japan and China have extremely different types of government, with China being rather authoritarian (which can be very efficient and beneficial when the people in power have the country's interest at heart, instead of their own), and Japan being democratic.
So if Japan can do it while still having a democracy, why can't Europe or the USA? The USA's problem (speaking as an American) is that it seems to be completely corrupt, much like Mexico but not at the lower levels like Mexico (where all the cops are corrupt; here in the USA, the everyday cops are mostly good, but the politicians are all corrupt), and no one wants to admit it. I don't know that much about European politics, but it seems like they're doing a lot better than we are as far as corruption goes, though their middle eastern immigrants are causing them a lot of trouble. If they were really smart, they'd kick all those people out, and only let in immigrants from other places like South America, Africa, Russia, etc. (and only so many from each place, instead of allowing one group of people to dominate). Remember, they just got the LHC going, something we can't do in the USA because of how screwed up we are: we tried with the Superconducting Supercollider, but that imploded. One big thing I see that's different between Europe and the USA is political parties: we only have two that are allowed, whereas they have tons of them, and it's not a big problem with new ones gaining power.
Of course, figuring out how to mass produce extra strong carbon nanotube ribbons would be very useful for things other than building a space elevator.
Sure, that research might cost billions but the benefit is not just the ability to build a space elevator. By all rights the cost to develop such technology should be divided over all of the gains that the technology brings.
"In America, first you get the sugar, then you get the power, then you get the women..." -H. Simpson
No. It's not even easy if it is stationary. Actually, I think it would be easiest if it were above the highest point on it's axis, and allowed to go around the world with the weather conditions...
Atmospheric conditions would probably be the biggest challenge, they would add a lot of force. Add to that the Coriolis effect for the car (or a similar effect based on the rotation of the earth), and then you get some challenges.
Still, if the terminal is high enough, it would provide an interesting form of global transit - fly to the terminal, ride it until you are close to your destination, and fly down.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
Look, let's just ring up General Products. The Puppeteers probably make exactly the kind of cable we need.
Whoever calls, pick me up a Number Two hull if they have any left. I'm good for it.
No... First: any mass at ANY [circular] orbit will remain at the same altitude indefinitely. (You don't see the GPS satellites leaving orbit do you?) A mass in geosynchronous orbit has the additional property that it also stays fixed relative to the earth.
Second, the orbit doesn't need to supply [significant] tension. For every newton of mass you lower towards the earth you simply place an equal newton of mass equally farther out into space. As long as the center of mass remains at the geosynchronous orbit all forces cancel out and the object still stays fixed relative to the earth. The item could reach all the way down and tickle the surface of the earth and yet wouldn't be pulled out of orbit in either direction.
Third, you don't need to solve "the tidy little equilibrium problem." Simply attach the tether to the earth (Ecuador is an excellent spot for this) and place the center of mass slightly beyond geo orbit. This will place a permanent tension on the tether. You can climb with any weight that is less than the amount of tension. You may accelerate with a force that keeps the combination less than or equal to the tension. You can do this without any regard to maintaining any equilibrium. And even if you did it is easily achieved. Simply attach the tether to a winch. Want less tension? Reel the whole thing in. More? Reel it out. The servo control for this would take something like a day to setup.
You need to retake Newtonian Mechanics my friend. The mechanics of this system are easy, well known and have been around since the beginning of the twentieth century. The material sciences is the main thing holding this from being a reality. Carbon nanotubes are the first, and so far only, material which promises the performance we need. (currently 10% of required strength and insufficiently long)
I will never live for sake of another man, nor ask another man to live for mine.
And why would you want to go all the way to GEO anyway?
To go to work at centerpoint station? The station that builds/deploys the ribbon/s? Anyways, the problem with releasing early to get into LEO is that your orbital period attached to the cable isn't fast enough for LEO, thus you're going to end up in a rather elliptical orbit. Not insurmountable, but a pain.
If we actually get this built, I see the ISS being relegated to the same status as Mir.
If they're trying to travel to the Moon, I imagine they'd want to stop off at some space station first (which again, might not be in GEO)
Actually, it might be even further along. You're probably going to want a ribbon going out the other way to make the center of mass the GEO. You can use the other length to set up a slingshot.
I don't read AC A human right
SDI doesn't need to be 100% effective to change the way a rational enemy with a few missiles will behave.
Besides it's really a first generation flying saucer defense system. You've got to crawl before you walk and walk before you run.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Wikipedia has an indirect link to a 2002 paper where a microscopic nanotube was found to have a tensile strength of 0.15 TPa, which is easily strong enough. Even if that was wrong, I see no reason to expect the theoretical calculations to be so far off as to make a perfect structure lack enough strength. Whether they would last long enough to be useful in a space environment, with all the high energy radiation there, is something I wonder about. Can they be repaired in place as fast as they decay, or how much of a cable's life would be spent hauling up its replacement?
It does seem much too early for the Japanese (or LiftPort) to be getting serious about building a space elevator. I suspect that is more for the buzz, and the genuine hope is that the research dollars they generate will pay off in more mundane uses of super strength materials.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
You ever play Civilization on a harder setting, and get busy with a few wars? Even little ones, but you're moving your units over and it's taking time and funding which adds up... then all the sudden another race starts building the wonders?
That's usually a sign the game is about to go downhill fast if you don't get your crap together and focus on your tech tree.
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