Going Up?

Do they need solar panels on the climber? Is it possible to just send power up the cable?

Ian-
The short answer is no.
The elevator will need the same amount of energy to climb the cable regardless where that energy comes from. Solar panels on the elevator itself are the best way to get that energy. The two most obvious alternatives to solar panels on the climber are fueling the climber (gasoline, hydrogen, ect), or transmitting the power from the ground (which could be generated any number of ways. In both cases, the biggest problem is in the weight. The amount of fuel the climber would require would be significant, I am guessing somewhere in the tens of thousands of gallons.
In the case of transmitting power, you would need a conductive cable. That would be a metal cable. In order to transmit the power needed to move the elevator, that cable would need to be fairly thick. Even having a metal cable as thin as speaker wire would snap under its own weight at the length required for the elevator.
So no, it is not possible to send power up the cable.

I'd hope they would find a way to trasmit power to the lift. I'd think they could use the carbon cable to support an electrical delivery cable without the metal snapping under its own weight as it were. It's most certainly better to add weight to the carbon cable instead of the lift.

I have three questions am unable to answer, perhaps a physicist may shed some light.
1)Assuming the ultra light carbon nanotubes weighs x kilos per mile, how shall they get x*62000 kilos to space so as to start drawing the cable downward till ground (assuming they opt to do it this way). Lets not opt for helium balloon to lift this cable as balloons can only go a few miles before they loose their effectiveness due to ambient air thinness.
2)This cable will pass the ionosphere on it's way downwards, assuming the cable will conduct electricity as it is made out of carbon, this cable may provide a vehicle for the vast number of electrons found here to reach the lower levels of the atmosphere where these free ions may be captured by positive ions.
3)How will the cable void being the vehicle of choice for electron transfer between ground and the clouds (and between lower clouds and higher clouds) in stormy weather, will the cable sustain such loads of electrical current. Lightning is usually brought about by such activity.

Allan.

NikoT: Carbon nanotubes can be excellent conductors, so a power cable would not need to be made of metal.

Allan: In answer to your first question, one posited plan is to haul up a very thin cable, and use that to haul up a more substantial one (and so forth if necessary).

I think positioning of the cable anchor close to the equator is the main proposed way of minimizing lightning strikes; but you're right, there's no complete answer to that yet. Perhaps some sort of nonconductive insulation on the vulnerable parts of the fiber would be possible.

If the cable conducts electricity this seems like a much better way to ferry power from solar arrays in space than microwaves that could potentially damage where they hit.

if space elevators became fairly common, couldn't there be a potential problem with travel by air (planes, helicopters, etc.)? or would they primarily exist on a temporary basis? there might be something i'm missing here, but it doesn't sound completely practical.

What about reentry? Will it be travelling slow enough to not build up enough friction to make it an issue?

they way to power the elevator is with a stationary laser at the base of the nanowires. since lasers travel in a strait line, it will always hit the solar panels unless interrupted by an aircraft, asteroid ect.
reentry... possible to have a heat sheild, but that might be tricky.

(plus the laser would have to be big with like a million watt diode) [exxaggeration may have been implied]

to strictbusinees14, aircraft strikes are not impossible but the airspace around it would be controlled much like the airspace around military bases, forest fires and other special exceptions. Pilots need clearance to enter these zones but potential terrorist attacks could still happen although I imagine the military would have a close eye on it.
Thank you Paul Adams, I was pretty sure carbon nanotubes were almost perfect conductors, perhaps though it makes a difference if the tube is not continuous from end to end. They don't say if the nanotubes would be woven together from shorter strands or if they could create a continuous tube that would span the entire distance. From my understanding they haven't been able to create tube of significant length.

In fact, when Boeing built the first 787, one of the concerns was how to handle lightning strikes.

The problem is that even though the carbon construction fiber is relatively non-conductive (as compared to a "true conductor"), there is enough conduction as a result of the "other" components that the heat generated as a result of a massive voltage/amperage multi-pulsed load (characteristic of lightning strikes) would cause the structure would heat at the strike contact point and possibly vaporize some of the carbon and form ionic carbon dioxide (which is a much better conductor than the carbon itself). The solution was to embed a copper foil mesh just under the surface of the outer carbon layer and provide an "entry/exit" pathway for the strike. One other characteristic of very high voltage events is that the electricity is carried as a "skin conduction on the surface" (current only flows through a very thin layer - the "corona effect" is what it's called). The intent was to give a "through path" for the power to pass around the outside of the aircraft and re-enter the atmosphere for its trip either "up" or "down" ("to" or "from" the cloud to "earth" - meaning a different "potential" - as applicable)

I can see that type of "elevator" construction "possible", but the weight penalty could get excessive - remember - everything needs to be put "up" there in the first place. the copper would be, in effect, a "parasite" (necessary, but not as a structural load carrying piece)

BTW - There's a reason lightning rods are attached to grounds with #10 (smallest I've seen) copper wires - the heat generated as a result of a strike will heat the wire quite a bit. It's even possible to "burst" copper wire (literally "explode" - vaporize - say a #30 wire) by applying a pulse of sufficiently high CURRENT. All the wire burst experiments I've ever seen don't have anywhere NEAR the power of a lightning strike, though - "millions" of amps - plus the wire burst is a "single electrical discharge" event - no small amount of electrical power, but nowhere close to an atmospheric lightning discharge

Ridiculous! the number of variables and potential problems to arise make this an impractical, un-logical pipe dream. The effects of wind current, wind storms, space debris, solar flares, thermal loading, expansion and contraction, thickness variations, lightening, and effectively shorting the ionosphere to ground will put the price tag high enough to bail out Wall Street!

Don't be ridiculous yourself. The cost of this technology would be irrelevant. The first country to develop such an elevator will effectively control access to space. Talk about priceless. Of course there are hurdles to overcome. Every great technological accomplishment in history has been viewed as impossible and preposterous by most people. The visionaries view impossibility as irrelevant and cost is just another hurdle.

For you technos, consider that the power used to climb the thread could be mostly recovered from gravity on the way back down. There would be some loss that could be recharged at the ground.

Hey Guys and Gals,

Just a thought, a lot of you gave your ideas regarding the space elevator's source of energy for going up or down. What if it would be similar to an ordinary elevator - that is - place a counterweight at the top that is heavier than the "things" that will be loaded. It's locked in place up there, then when it's time to put some cargo "up there", the "locks" could be released then let gravity do the work - the counterweight goes down and the "cargo" goes up.

The only problem that I see is getting the counterweight back up again. Well, at least it could help in lowering down the "power" requirements for this thing. I know it sounds like a crazy idea given that everything has to be super-strong because of the "stress" and the Gs involved. But that's just one of those crazy ideas that came to my mind.

By the way, it's now 2008 and isn't it about time for our Space Odyssey?

Here's the thing about powering the climbers. They are most likely to be powered by power beaming. This technology is in development and works like this. You convert electricity to microwave radiation in one place and from there you beam it to a receptor which converts the microwave radiation back to electricity. That seems to be the most promising technology for powering the climbers. Power beaming is also likely to be among the first commercial uses of space aside from communications. Solar power collected with greater efficiency in outer space will be beamed down to earth to provide clean, essentially infinitely renewable energy.

Somebody mentioned lightning strikes. Lightning strikes are a potential problem, but the idea of using some kind of lightning rod to protect the tether is not so far-fetched. While I'm not certain of the highest altitude occurrence of electrical storms, it is inside the atmosphere, so the added weight from a lightning rod would only affect, at most, the bottom 80 miles of the 62000 mile tether. It would likely not affect the strength requirements of the tether all that much.

As for airplanes, the tether would not be put anywhere close to major air traffic routes, and navigational systems can easily steer airplanes clear of it.

Of course there is a lot to overcome before a space elevator can become a reality. We need a higher strength tether material. We need to improve power beaming. We need climbers that can either ascend rapidly, or slowly but with large payloads. Despite these challenges the benefits of a space elevator are enormous. If it can really be done for only $10 billion, it would be a fire sale price tag.

Carbon nanotubes are classified as metallic because of their molecular structure and can carry an electrical density 1000 times that of copper or silver, not to beat a dead horse, but again why then can't we exclude any copper wire conductor and send power straight up the carbon nanotubes while also using the same tubes as the load carrying cable?

I see how using power beams can work but they are very inefficient, if they weren't then we would use them all the time for power transmission.

I'm just throwing this out there, but if lightning strikes would be so common then how about channelling that energy into a large heat sink like a large tank of water and use the hot water to heat a refrigerant medium that would flash off to spin a generator? Then we could harness lightning with a massive array of space elevators and conquer the world AHAHAHAHAHAHAHAHA! Sorry it's time for my medication again.

if you have read on it at all you will find out the plan on useing lasers as shown on the picture to send soloar energy up to the lift in the spectrum that solorpanles operate best at. sorry about the spelling to lazzy to spell check =p

if you have read on it at all you will find out the plan on useing lasers as shown on the picture to send soloar energy up to the lift in the spectrum that solorpanles operate best at. sorry about the spelling to lazzy to spell check =p

And if you had seen the results of university competitions to harness that energy with a climber then you would know that they barely convert any of that energy at all.

It is possible but inefficient.

Being a conductive ribbon, spinning around the earth's magnetic field, wouldn't it be possible to generate electricity on it's own? If the cable was actually a loop, then I would think it would produce a sizable electric current. For example, the ribbon could be two ribbons with an insulator inbetween. A switch at each end of the ribbon would hold one end open, while the other was closed. Contacts on the climber would conduct from each side of the ribbon, closing the circuit. The solar winds are holding the magnetic lines of force around the earth, perpendicular to the sun. The loop of this conductive ribbon would be spinning through the lines, making it a giant generator. Remember the shuttle experiment a few years ago?

The ribbon doesn't actually move through much of the earths magnetic field so it would generate very little electricity. Since the elevator has to be in geosynchronous orbit, the tether and the earth's magnetic field rotate at the same rate.

Somebody mentioned sending electricity up and down the tether. I think that would be difficult due to the tethers length. 62,000 miles makes for a lot of resistance, even with carbon nanotubes which have very low resistance. Also, it's my understanding that the resistance is very low from one end of one tube to the other end of the same tube, but that resistance from one tube to another tube may be somewhat higher. This is because of things like the arrangement of the carbon in the nanotube, i.e. its geometry, and the resistance in whatever epoxy or other compound is used to hold the tubes together.

Aw cmon evey1 knows its just bs......we have better things to worry about.

Um, no everyone does not "know" this is bs. All your comments certainly are though.
I think it's something that needs a lot more research and development, but through years and years of learning it might be possible. Kind of like your potential normal kid.

Not all my comments are tough.

But ty anyway

The Tether will be thicker on the Earth surface than at the counterweight. As the car goes up the, counterweight loses energy and will come down. When a car comes down the counterweight goes back "up". The mass of the counterweight determines how much weight the Tether will handle.

If a plane runs into the Tether, then the Tether will stay put, it's in geosynchronous orbit(GEO). Plus its very strong.

A Tether moving though the Magnetic Field will generate Electricity, An elevator would be able to generate some because the magnetic field fluctuates.

You could put solar cells every so often on the tether once it is out of the atmosphere.

To install the Tether a rocket would carry a "spool" of cable up to space and then the spool would send a "wire" down at the same time it sends the counterweight up.

The space shuttle costs $10,000 a pound.
The space elevator costs $200 a pound.

At 1000 mph it would take 26 hours to get to GEO

As Author C Clarke said "When your at GEO your half way to everywhere!"

Engineers look at Delta V to see how much energy it takes to go to another planet or a moon. Just getting to Geo is close to one half the Delta V it takes to get to any other place in our solar system.

A great place to start is at tethers.com

What about space debre and other satellites.

-THE KID

Won't the solar winds tear up the elevator?

No energy beams! If I had anything to do with this elevator, i.e. if I was a passenger or had cargo on it I would not want high energy microwaves or lasers pointing at me in the climber or anywhere near the cable. Can you imagine the cable being cut by its own power system?

-I believe Lightning happens mostly in the lowest part of the atmosphere.

-There are of spacecraft, satellites and and space junk in low earth orbit to be concerned about. The military can't stop that.

-The cable wouldn't be a straight line: Low level winds and the jet stream will affect the cable and the climber at higher attitudes. Solar panels would act like wind sails. The capsule would need to be streamlined like an aircraft.

The tether 'could' be a loop, rotating the loop with an electric motor at the bottom.

Cargo containers could just latch on for the ride up, detach, unload and load for the return trip.

Multiple containers, could be on the way up and down at the same time, balancing the load.

Make that SHOULD be a loop...

To generate a current, you need motion through a magnetic field, that would include, the linear motion of a loop in both directions.

The tendency of high frequency AC, to travel to the outside of the conductor is "skin effect", but the linear motion would produce direct current. DC.

Geosync orbit is 35786 km which would require a loop length of ~72 km.

The big problem would be tidal force in that the loop would be under tremendous tidal stress.

One way or the other, move away from the equator, because if it snapped it would wrap around the earth. It's ends would hit the earth, at a very significant impact speed and energy. (a stonger than steel bullwhip?)

We live in amazing times...

By the way, microwaves beamed in from the communications sats in the same orbit have the footprint of 1/4 of the u.s.
Microwaves are anything but coherent, and light just doesn't have the power yet.

Chipper Smoltz, docjohn52 and I are thinking alike: A moving loop seems like the way to go. It could be powered by a ground based electric motor possibly augmented by a solar powered electric motor at the top.

this sounds a lot like the space elevator form Aurthur C. Clarke's book, the fountains of paradise, did that occur to anyone else. also as an alternative to using a cable could we launch spaceships using electromagnets? put a super power electromagnet on the bottom, or if that wouldn't work then what about using it to achieve the initial acceleration, then the rocket just has to keep the momentum up. would that work?

could the lightening from the strikes that are bound to happen be brought back to earth and turned into usable electrical energy if we could do that, wouldn't the elevator pay for itself electrically?

""""Will the Japanese be the first to elevate to space?""""

No.

The most baffling, head-scratching notion to me is the idea that a technology that's in its very early experimental stage (carbon nanotubes) is going to lead directly to a space elevator. It won't.

Manufacturers are only just now using the technology in tennis rackets, and, long before we can have "space elevators," the material has to be used extensively in car and airplane bodies, bridge construction, other structures, etc.

As a matter of fact, when I think of carbon nanotubes and Space, I think of rocket fuselages made of nanotube-derived material so that single-stage-to-orbit launchers would be much easier to build and operate, even with conventional rocket propulsion.

The next step would be space tethers dozens of miles long, rather than 22K miles of "elevator." A tether suspended from a space station could grab sub-orbitally-launched payloads from the upper atmosphere, and reel them up into orbit.

After all that, then, MAYBE we'll be ready for a full-fledged space elevator.

While the thought of cheap(er) access to space is exciting, I think the real potential, the one that should really drive this forward, is safer/cheaper access to space-based-power(SBP).
I read somewhere that a 1km wide loop of solar panels around the earth at geo-synch orbit would produce more power in one year than all the fossil fuels (including Uranium) in existence on Earth. Ok, so that's a whole lot of solar panels, but with a space elevator it's not out of the realm of possibility. The space elevator would provide both a means of transport for all those solar panels (or solar fabric/foil) as well as a transmission system safer and more efficient than microwaves.
You want to talk about global influence? What if you controlled unlimited access to the next generation clean-cheap power source? It would be worth Trillion$$
How much did the Apollo project cost? Something like 4% GDP for 10 years. What did we get out of it? How much did the Space Shuttle cost? What did we get out of it? How much does 1 month of war in Iraq cost? $10 billion for a space elevator? Multiply it by a factor of 10, and it would still be a bargain, and we would get far more out of it than improved access to space. I don't care if it's 20 years from now or 200, the space elevator, when built, will be a game changer.

I still don't understand how it would work. How do they get the cable to stay in place? Is it connected to anything?

I think it would be a cheap way to get into space, but it would also cost trillions to get it built.

loafula, get your story straight before you dig yourself in too deep of a hole.
First of all, you are correct in your estimation of the amount of fuel needed to propel the elevator car through the atmosphere, but the likelihood of anyone even considering utilizing chemical thrust is far-fetched and defeats the whole purpose of creating an alternative to rockets in the first place.
And once again you are correct in your prediction that a suspended chord, even the thinnest of chords would snap under it's own weight, but yet again, you have misunderstood the initiative. The power cable would obiously be attached to the carbon nanotube shaft, eliminating the worry of a cable not being light enough and thick enough to support its own suspended weight from orbit.
Also, there is an annual competition sponsored by NASA to promote the civilian advancement of laser/light transmission to a small scale elevator car in the hopes that an efficiant system of ground-to-car energy transfer will be discovered by one of the competitors, and if anything promising turns up, it will be most likely utilized, because the elimination of the need for a conducting cable to run up the shaft will save thousands of pounds of weight the carbon nanotube wire will have to suspend

loafula, get your story straight before you dig yourself in too deep of a hole.
First of all, you are correct in your estimation of the amount of fuel needed to propel the elevator car through the atmosphere, but the likelihood of anyone even considering utilizing chemical thrust is far-fetched and defeats the whole purpose of creating an alternative to rockets in the first place.
And once again you are correct in your prediction that a suspended chord, even the thinnest of chords would snap under it's own weight, but yet again, you have misunderstood the initiative. The power cable would obiously be attached to the carbon nanotube shaft, eliminating the worry of a cable not being light enough and thick enough to support its own suspended weight from orbit.
Also, there is an annual competition sponsored by NASA to promote the civilian advancement of laser/light transmission to a small scale elevator car in the hopes that an efficiant system of ground-to-car energy transfer will be discovered by one of the competitors, and if anything promising turns up, it will be most likely utilized, because the elimination of the need for a conducting cable to run up the shaft will save thousands of pounds of weight the carbon nanotube wire will have to suspend

A Space Lift has a very fundamental flaw in it. An orbiting satellite possesses a certain amount of ANGULAR MOMENTUM which is roughly its orbiting speed times the radius of its circular trajectory. Since there is a law of physics that says that angular momentum must be conserved, this needs to come from somewhere. So as the lift with the new satellite is raised from the ground it would start exerting a lateral force on the cable in order to accelerate to its new speed which would have to go up all the time as its angular speed is fixed. This would exert an opposite force on the anchoring point is space which would in effect supply the angular momentum for the new satellite. The anchoring weight would thus need recharging by the use of rocket power to keep its speed. Thus there would be no gain, and this would cost a lot more as suppying rocket propulsion to a point in space would be much more expensive than just using a rocket on the ground. But it is an interesting idea…
The only way to solve the problem would be to use two cables at an angle. Now the extra momentum would come from the earth itself. Now that is an idea!
Lisbon, Portugal

Sniper 1 makes an excellent point, which is precisely why the elevator system should be two cables on a pulley system with loads on each cable that exactly balance. As one load goes down, the other comes up with only enough energy input needed to overcome friction.

The question is, what do you send down in order to bring something up? Well, we could gather up all the space junk out there and ship it back to Earth, which would be a good thing.

Better yet, we could mine the moon and the asteroid belt.
The moon turns out to be rich in titanium and heavy hydrogen. It may have other goodies as well.

I am, however, sanguine about the chances of the space elevator actually being built. It would take 60,000 miles of carbon filament cable for just half of the pulley system and putting that first cable in position is a very daunting task, not for the least reason that the cable is not uniform in thickness, but much thicker at both ends and very thin in the middle parts. Worse yet, what if the cable breaks? It could all come down and flail about.

Surely a better way to do it would be to have to have the wire "loop" around the satellite and go down to earth again and, as something comes up, ores etc and spacecraft would go down. As there would be ore etc coming down with the spacecraft that would mean that the energy require to run the elevator minimal. You may think this break the laws of thermodynamics but more stuff would be coming down than going up.

This idea has been put forward in some of the "Science of Diskworld" books and "The science of Dr. Who" books.

The minimal energy required to run it could come form helium-3 which could be mined on the moon. This isotope of helium would also be very useful in green generation of power

Dear Readers:

Here's a few other things to consider besides whats already been mentioned. At certain altitudes above the earth ,(Like 20 to 50 miles) The temperature of the sun and the cold of space are sufficient differentials to generate electrical energy, and I mean lots of it, through the conventional closed loop boil a liquid into a gas, turn a turbine and a generator and then condense the gas back to liquid again. Would new technology need to be developed to create a feat of this magnitude? Of course, Hey it's a brave new world and that's why we have both visionaries and engineers. Also to consider is that near half way to outer space you encounter half G forces. That is things would weigh half as much as they do on the surface of earth. Enormous structures could be built with little structural support at this altitude and micro gravity would be a benefit for returning astronauts looking to readjust, heart patients, research engineers looking for new places to experiment on everything from biological growth to manufacturing techniques. Unlike undersea exploration the construction of 10 to 14 psi sealed balloon or fabric like
buildings would be a snap. What a great place to study earth from and to study space from. It's the place we currently rush through and lose space shuttles in during the re-entry dash. It's where particles originate that ultimately cause lightning on earth. In our rush to get to deep space we've ignored this region. It's like rushing out to five miles offshore in a rowboat to explore the ocean you've never ever seen except through a telescope from 100 miles away. A smart person would stop at the beach, and study sea life in the shallows at the transition between land and sea. SEE! The Air Force had a project MAN-HIGH which put Balloons above 100k ft altitude. If they could do that in the 1960s, then we can do that TODAY, bigger balloons with better materials, and tether them geostationary in 3 places with cables. (Hey what a great test for carbon nano-tubes. Materials testing, health and weather research, spying on each other, the possibilities are endless and worth the expense to investigate. I proposed a space elevator a decade ago to folks who thought I ment the tower of Babel and who called me a lunatic. Yes well, they complemented lunatics like DaVinci, and the Wright Brothers too in putting forth ideas to advance the frontiers of human knowledge and achievement.

The issue of Nanotube Carbon conducting electricity from the ionosphere to earth and/or lightening, need not be an issue. Just because a steel cable cannot extend 62,000 miles, does not mean that that the carbon line must extend all the way from the earth. Rather, an insulated structure can be constructed from earth which will not conduct electricity or will do so in a way that can be harnessed and can be used for other things such as the above idea of taking advantage of the temperature difference (if there was enough cold mass available to cool a fluid quickly enough of there). From above the ionosphere the nanotube carbon can then take over carry the load of itself and help support the structure which extends for the first 100 miles.

I would imagine that you would have to build such a cable from the geostatic satellite down to earth, as the other direction would be fighting gravity, so stiffness would be required. However as the earthbound cable would have significant mass, it would tend to lower the centre of gravity slightly, requiring an orbital correction to maintain geostasis. The alternative strategy would be to build outwards at the same time, thus maintaining CofG at the same orbital distance.

However, any construction in either direction would have continuous angular momentum and so tend to curve away due to the Coriolis effect, rather than grow in a straight line. The outer construction would curve backwards with regard to orbital rotation, while the earthbound cable would curve in the direction of the orbit. This would require energy to counter (perhaps using correctional jets?) and would pose some interesting computational problems

I would picture the orbital station as being a mushroom shape, with the mushroom cap providing the mass to counter the earthbound cable. I did wonder if things would be any easier if the mushroom was made to spin, giving the opportunity for artificial gravity, but of course this spin would pose a problem due to gyroscopic forces as the station proceeds round its orbit!

Hi,
In response to Sniper1's point; two cables are not necessary, as long as the centre of mass of the cable is further than geo-stationary height, rotational inertia (centrifugal for the old fashion) will pull the cable back to the upright (oscillation could occur if not managed). You can see the same issue in a helicopter blade where there is a pivot on each blade close to the centre axis (not to be confused with the swash-plate pivot). This allows blades to slow down going into wind and speed up downwind. The rotational inertia of the blade keeps it more or less in place.

This could also shape the space tourism industry by sending people up the elevator. If someone could create this, they would be rich.

So many Einsteins out there saying "you cannot do that". If it were to be suspended from, say, 3 points around the poles [our axis of spin], as 3 point suspension is unbeatable for structure and stability- we might not have to deal with the atmospheric friction, nor need a motor to spin it for the enetgy generation that may be possible. These are new days. "Ask not what science offers you; ask what you can offer science." Get an education before you shoot your smart mouth,"everyday normal" kid. Its easy to poo poo what becomes routine before we realize what it takes to get there. Youthful ignorance is simply parasitic to educated prowess, and is nothing to be proud of. Remember Eniac? Computers are not possible. Right?

The thing about the poles- sadly, we only have 40-50 years to keep them there before they melt. We better try, or stop whining about what is not posible.

"The Duty of Privilege is Absolute Integrity." John O'Donohue, poet, philosopher.

It's pretty sad that the U.S. has envisioned this technology for some time now. But, we have NASA to thank for our lack of action. While they experiment with rats in zero gravity and waste time and resources dreaming of putting man on Mars, the Japanese are pursuing a useful technology that will ultimately add billions to their economy. It is time that our tax dollars at NASA are put to work for the American people - not a bunch of spoiled space geeks.

Ok... So lets assume the following...

We create a cable to tether an elevator.

We have a power source to move the elevator

We have a GEO Sat in place to receive the payload.

What's going to keep the GEOSTATIC SAT in place during payload transmission?

Its like trying to Pull a parasail with a submarine instead of a boat. Did I get this analogy somewhat right?

We can rely on Inertia, but how much mass needs to be in orbit before we can reliable use it? Are we going to use maneuvering thrusters to keep the station in place during payload delivery during a storm? And how is this going to effect tensile strength of the tether since now we have to deal with not only gravity but inertial momentum? Doesn't the Space Shuttle have to roll to leave the atmosphere?(is this relevant?)

I'm not as educated as the rest of you but these questions seem necessary.

I think everyone is forgetting about the mass of the earth creating what is called "frame dragging". The earth distorts space time and because it revolves it extends this disortion outward, dragging its distortion of space time with it. Such a long cable, of whatever non-obtainium material, will be dragged along with the earth's effect on space time, distorting the cable along the earths axis. The length mentioned would have to be even longer to reach the distance needed.

Cool idea but what about the laws of physics ? As the climber reaches the end of the tether a minute amount of momentum will be stolen from the Earth's rotation and in fact slowing the Earth down. Yeah in the future leap seconds will have to be added more often and maybe we will be facing the 25 hour day sooner than later.

Jese u guys they can send
electricity through moded
microwaves.

Read a book

how about some sort of helicoptering/electric powered platform that just uses the thread for guidance/energy, then shifts to some other sort of propulsion as it enters more space-like conditions... using the thread more as a guidance/energy collection- carrier-provider system than a lift per se

I think that the elevator idea is pretty cool in itself, but if basically one bad thing hapenned it would be the end and the japanese would have to build a new elevator. Also if anyone was inside the elevator and the cable snapped say bye-bye to them. I still think it is a good idea but they should wait until we have more advanced technology.

Good idea, although we will never see it in our lifetime even if you were born tomorrow. way to many variables (planning, materials, environmental etc...) in every aspect of this thing. It'll be in the same category as the "yesterday's beloved technologies of tomorrow" thought of but, never built.

http://www.popsci.com/scitech/article/2008-12/dude-wheres-my-flying-car-and-jetpack-and-armies-robots

To prevent strikes from satellites, space junk, debris, etc, would it be possible to attach such a space elevator to either the north or south poles? Not the magnetic ones mind you, but earth's axis.

Also, wouldn't building the elevator on the equator create structural problems regarding the moon's gravity influencing the pull of the tether away from the earth?

I like this idea, but there are some pretty big technical hurdles that must be crossed in order for it to succeed. But it's been mentioned before that the first to control this tech will control space.

Thanks!

Would be nice to have an elevator to bring things to space/vice-versa. Makes sending things cheaper in the initial cost. Possible way to send power down from space if we decide to use solar panels and have a direct plug rather than microwave/laser.

Though it seems that there are A LOT of risks to account for... primarily what if that giant elevator collapses due to natural or mechanical errors...some already stated by others.

problem of repairing that giant thing.
Elevator Jams/failure
Lightning strikes
Earthquake (small possibility even in the most remote place)
Ease of repair for nanotubes
Access to damage points
monitor of the entire integrity of elevator
weathering
security from attacks (who is going to protect it?)

Obviously letting that giant thing fall is not an option, what precautions can be implemented aside from keeping it well maintenanced (look at what happened to columbia shuttle). Little(not very little actually) slip ups won't just result in 7 deaths.

Overall, of course it's a fantastic idea of going to space. There are great possibilities if it's successful.

though i personally think it would look ugly to have something jut out of our earth like that haha
Sure is an alternative to get to space :)

Everytime you put something up, you have to bring something down, right? Otherwise, the satellite would have to expend fuel to maintain synchronization with earth.

What if we made the cable hollow, so it is a pipe? Fill the pipe with a light gas and move gas up and down the pipe as a way to counter weight.

As the gas rose or fell it would change density. This would match the surrounding pressure within the earth's atmosphere, keeping relative pressure somewhat constant.

Elec through the cable? Not likely. Any resistance at that distance is going to cause major power loss into heat. Too much heat at the power-up, too little juice at the far end.

You most likely system for going up the ribbon would be an autonomous climber relying on solor power. Yes, it would take months to get to the top, but the SE isn't to put people up there, we have rockets for that, but to put materials up there.

Space doesn't need lots of people, just lots of materials. Something that could do around 5mph for 10 hours a day on solar would only take less than 3.5 years to get to the top. If you are building a robotic mining operation on the moon, an artifical-G capable biodome ship for long-term planetory exploration, or just putting some "Rods from God" up there, 4 years is more than fast enough.

As for bringing stuff down, that would require almost no energy at all, only a breaking system that kept the load coming down at 5mph (even so, it would be returning in half the time, which would be important if you were doing any signifigant lunar mining (a solar powered assender carries up several unpowered decenders which are loaded and sent down).

The problem is that we all know how space technology works. Space is a tough environment. Somehow we always fail to account for that and things such as the shuttle and the ISS end up costing much more than anticipating.

While I love the idea of cheap access to space, I don't think this would be as cheap as everyone thinks. First, they have to build several levels of safety precautions into it which increases complexity and increases the chances of it breaking. FOr example, how do you protect the cable from a 25,000 mph hammer? I really can't imagine the damage caused by a 62,000 mile long cable wrapping itself around the earth several times. This would be an engineering first with new materials and there would be lots of problems along the way as well. In the end, there is great potential for error and poor design and the cost will be many times what anyone will estimate simply because the designers are always optimistic people.

"Most of a rocket’s fuel is spent blasting through Earth’s thick atmosphere and out of the planetâ€s strong gravitational field. "

Actually, most of a rocket's fuel is spent on acceleration to counteract the planet's strong gravitational field. It extends well beyond the moon, which only dominates part of it's own orbit.

A conventional geostationary satellite is not be able to hold anything else up - the "anchor" for a space elevator has to be well past the geostationary orbit.

Bob Stuart

We can change anything.
But we can never change
just one thing.

just thinking about it falling to earth, probably close to or just over one wrap. brings to mind the norse belief that a worm ends the world by encirclement.

I have read the book be Clarke and a similar one that I am sorry that I can't remember the name of.
Here is how to understand the idea.
Imagine a ball on a string. Swing it in circles over your head. Centrifugal force makes causes it to defy gravity. Now imagine that you are the earth and the ball is a space station. The thether (String) will be kept taught, like an rigid object. The earth is rotating with a ball on a string, defying gravity. Now IMAGINE a simple machine that has two wheeles that pinch the string from opposing sides, and spin in unison, to climb the string. It can be powered by a diesel engine that is equipped with pressurized air tanks to feed combustion after leaving the atmosphere. Imagine a semi truck with the wheels angled towards each other, gripping a cable and climbing up.
This idea is the biggest leap in human imagination since the invention of space exploration. We could very well see it in our lifetime.
Let me take your imagination further. Lets make multiple strings from the equator to space stations in orbit, like spokes on a bicycle wheel. Now imagine the wheel that circles the earth. Now imagine the wheel to be a rollercoster track like the BAT at kings Island. Imagine a tube with life support that extends completely around the track that is encircling earth. It would be like a car tire or hula hoop that you could live inside of. Now imagine that this tube was powered to spin faster than the earth along the fixed track. Fast enough that centrifugal force would allow people to feel artificial gravity. Their heads would always point down towards the earth while the C-force would try to fling them into space, stopped only by standing on the inside of the tube. The idea can go further, but would need thousands of words to impart.

I think it might just be more effective to keep learning about electromagnetic force generation. As written above, a track circling the equator that uses maglev tech to throw mass into space. Just create an airframe that can pop wings out at that speed, and there it is in space, no muss no fuss. As it is now, our supercolliders are just wasting billions on tech that will take hundreds of years to come to fruition. Higgs Bosun? What are you gonna do with it? Kill this world for mass to start another? Elevator? We have no idiot proof way to control its placement, even if built. The variance between the planetary speed and the atmosphere above it is enormous when attempting to move your spacestraw through the wind and match the increased speed of the planet to mount it. I saw a piece of straw in an oak tree from a tornado once. It was interesting, and sobering. A nanotube would rip itself apart with vibration. Scientists should be working on perfecting the things that Do Work. Get real.

this is an eight track tape player; if the japanese want to play around with this, they can knock themselves out.
let's spend the 200 years and 10 trillion on teleportation.

first, to Mars

The space elevator,if it is ever built,will be good only for geostationary vehicles or longer haul interplanetary vehicles in a preliminary geostationary parking orbit. Why? Because at orbital altitudes above and below 36,000 Kilometres, a vehicle is travelling relative to the earth and by extension,the elevator itself. Example: Trying to climb the elevator at (say) 50km/ hour vertical velocity, and then reaching the desired operational orbital altitude (eg 400km), means that on release from the elevator the payload falls vertically downwards back to Earth. You still need to give it a horizontal (orbital for that altitude) velocity to stop that happening. So.. you will have to carry some sort of propulsion system anyway.
More mundanely,despite the probable development of technologies to build the elevator,it would be such a tempting target for terrorists that it could never be sufficiently protected.

I think this idea is really crazy, but actually it is useful for everyone. difficult to achieve and affect air traffic, such as a question to my mind gets stuck

www.misschat.net

The payload would have to be pulled, once released from the tether, into the docking sat. New containers would replace old.

We WANT the electricity generated by the voltage difference between hubs, the superconductor carbon would collect and deliver it.

Any load that is not in balance, simply taxes the motors.

Motors at both ends is a given.

And security, would be a bitch. If it breaks, it would hit the earth, with the vengeance of a bull whip. Times 56,000 miles...

Just a thought.

"Only two things are infinite, the universe, and man's stupidity, and I'm not sure about the universe..."
A. Einstein

(Im)practicalities of getting the materials to orbit....

Right now the only feasible method of getting the vast amount of material to GEO to start such a project(*) is 1950s Orion technology. That isn't going to happen without a LOT of horsetrading, no matter how clean the nukes used may be.

(the tether is fed outwards and inwards at the same time to balance forces. End result is a whip at 2*GEO which gives a very cheap launch cost for interplanetary work. Once grounded and tied down, Any climber mass has to be balanced by an equivalent mass on the whip end. People, please READ ACC's story, he thought through a lot of this already)

There are alternatives which are easily doable with current technology right now, such as Heinlein's launch belt or 1950/60s technology Sea Dragon launchers (the latter is built in a shipyard using 8mm submarine steel). The problem is high initial cost (RISK to investors) and the unstated risk of virtually destroying the existing space industry should they prove sucessful - either of these would drop payload mass-to-orbit costs by 90% if sucessful.