Space elevator. Dream, hoax or reality?

Granted if the air were to travel the entire distance this would happen, however if there were a series of locks and stops along the way then that problem could be avoided.

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Granted if the air were to travel the entire distance this would happen, however if there were a series of locks and stops along the way then that problem could be avoided.
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Not so. The total length will remain the same whether you divide it into 10 or 10,000 pieces. You have also added more energy loss because now you have multiple locks and stops that themselves take energy to open and close and have a certain amount of leakage. You could add solar panels to the orbital part of the skyhook to get power but then you would be adding mass and your cable would have to be wider or stronger. I think reviving project Orion for the short term would be much more economical for boosting massive loads into orbit than attempting a skyhook at this point. You're going to have to lift all the skyhook mass anyway.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote><BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote> Granted if the air were to travel the entire distance this would happen, however if there were a series of locks and stops along the way then that problem could be avoided. <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote> Not so. The total length will remain the same whether you divide it into 10 or 10,000 pieces. You have also added more energy loss because now you have multiple locks and stops that themselves take energy to open and close and have a certain amount of leakage. <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote> Jeremy's analysis is correct. Besides, if you have to slow down to less than about 2000 km/hr to traverse the locks, you might never get there.

Any system that can store energy when a mass is lowered, for later use in raising mass, can compete with the space elevator. How are you going to do that with a rocket based system? (You COULD land the rockets on a Really Big Spring, or a Huge Solenoid. <BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote> I think reviving project Orion for the short term would be much more economical for boosting massive loads into orbit than attempting a skyhook at this point. <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote> The Orion concept has a lot of practical problems - nuclear thermal rockets are a better idea technically and economically. This type of engine has actually been built and tested, Orion has not. But political and social considerations will prevent any machines like these from being put into service for the forseeable future. A possible exception would be for space-only applications where the rocket never gets closer to Earth than geosync. (Nuclear power scares us. Perhaps it should, at this point. But we will eventually learn to use it and even greater power.)

But this would still be a rocket based system. Unless you then add some sort of energy storage mechanism it will never be as efficient as a beanstalk.

For moving efficiently between a planetary surface and orbit, or from one orbit in space to another, it is really hard to beat a skyhook or its derivatives. Going somewhere for the first time, of course, still takes a rocket. <BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote> You're going to have to lift all the skyhook mass anyway. <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote> Most (almost all) of the shyhook's ultimate mass will be lifted with the skyhook itself. Even when you are lifiing mass without a counter balance an elevator is better than a rocket. (You guys would really be doing yourselves a favor to read up on this stuff instead of just taking wild stabs in the dark. A lot of serious work has already been done.)

Regards,
LB

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote> The Orion concept has a lot of practical problems - nuclear thermal rockets are a better idea technically and economically. This type of engine has actually been built and tested, Orion has not.
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Orion has been tested, but only on a small scale admittedly. That is still farther along engineering-wise than the skyhook. Freeman Dyson thinks it is quite doable from an engineering standpoint. So you build a big floating platform out in the middle of the ocean somewhere.

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But political and social considerations will prevent any machines like these from being put into service for the forseeable future.
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Probably true, but should it be this way or should science not cave in every time some person has irrational fears?

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Most (almost all) of the shyhook's ultimate mass will be lifted with the skyhook itself. Even when you are lifiing mass without a counter balance an elevator is better than a rocket.
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The initial platform has to go up to manufacture the first cable. That platform is not light. Orion could do it in one launch. The cable can be manufactured in orbit and lowered down but you have to lift the mass of material up there in the first place in order to make the cable.

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You guys would really be doing yourselves a favor to read up on this stuff instead of just taking wild stabs in the dark. A lot of serious work has already been done.
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I know a lot of serious work has been done and I am not saying it is impossible. Skyhook only has efficiency if the load coming in roughly equals the load going out. If you can show me compelling evidence that that will be the case then I will be more interested. Once the hook is built we will want to build big space stations and start taking out material to make moon bases, moon based radio telescopes etc. What mass are you going to bring back to balance this tremendous amount of material? It will be some time before moon or space based products will be created to ship down and most of the material will itself come from the Earth for a long time.

This is a perfect time to say my idea: if we send missions to mine astriods and pther planets then we could get supplies from the universe which would tehn allow us to get material from the moon,(m/b)a close astroid. Have any of you heard of Ion propulsion we could get to the moon and the places easier with ion propulsion(if it is perfected)My conclusion is we stick with rockets(also ion propulsion) for now instead the space leevator because rockets have advandtages over the tower:
Rocket: Advantages- Goes into Geosync orbit, carries own fuel,
effiecient as far as money wise(compared to the space elevator)
Disadvantages- still cost billions in programs, fuel required in reentry to slow down spaceship.( also place name more on both sides for me)
Space elvator: Advantages-once in will shuttle a constant supply
Disadvantages- "only has efficiency if the load coming in roughly equals the load going out"(jeremy)


The intuitive mind

The soleniod idea seems better for a launch than a landing. Why not use solenoids to put stuff in orbit? That would be very efficient and cost effective.