Actually I was thinking magnetic motor, like in a monorail except vertical. No physcal contact between elevator and the support structure, supported and accelerated by electromagnets, so no friction.

It works horizontally because gravity pushes the cars down close to the magnetic track (rail gun). In vertical mode there is nothing to keep the cars next to the track unless you hang on to the track.

RE: wave motion: do you mean harmonics? Like the bridge that came apart back in the '50's?

No, I wasn't thinking of that. I was thinking more along the lines of a plucked string. All manner of things will pluck it. As long as they aren't near a resonant frequency they will die out, but they still have an offset. And you know that is many feet in the case of the tides. As to the jet stream at eight miles above the surface, I'd expect it could bend the cable a hundred feet off a straight line. Good enough pluck.

That was a harmonic problem that was easily corrected once the physics was better understood.

The physics was well understood. The engineers didn't apply it and ended up with a structure that had a resonant frequency that matched expected winds. Watched the film of that a dozen times in my physics class, then we got to calculate bridge loads on a test.

And, again, I remind you that low level atmospheric issues will be largely overcome by the sheer mass of the 99.9% of the structure that is above the atmosphere. Since we live in, and are utterly controled by, our atmosphere, it can be hard to grasp just how insignificant it really when compared to the mind-numbing scale of a 40 000 km long cable.

The jet stream will no more be a factor than an ant is pushing on the tire of a car.

Cable can't weigh too much. It has to be strung in the first place and in one piece as there is nothing to attach an end to while you splice the next one on.

As for the other issues (lopsided earth, etc) I haven't really thought those through yet. But, as I noted in an earlier post, earthquakes could well be the big issue. even a small one could be catastrophic given the mass (inertia) difference between the planet and a cable hanging from space.

Of course, I am stoned on NeoCitran and a 102 degree temperature at the moment, so what do I know. lol.

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though you'd have to find someplace equatorially that has very little weather. Thats hard to do over water. I'd think placing the elevator on stable land would be more appropriate.
I think its just so much easier keeping idoits away from your elevator by using a fence than the alternative on a body of water

Right on the equator is an area the sailors call the doldrums - typically NO wind. It is not too far either side where the trade winds are. Tropical depressions may start on the equator, but they typically don't stay there long enough to be hurricanes.

Doing building work at 1000 feet underwater is going to be EXTREMELY difficult. That is 30 atmospheres pressure. 10000 feet under water would be even worse at 300 atmospheres pressure. (Rule of thumb 30 feet of sea water adds one atmosphere of pressure - which is why normal SCUBA divers don't go below about 90 feet).

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BOINC WIKI

It works horizontally because gravity pushes the cars down close to the magnetic track (rail gun). In vertical mode there is nothing to keep the cars next to the track unless you hang on to the track.

The cable runs through the centre of the car. The car is propelled upwards by the linear motor of which the car and cable are both parts. The horizontal motion of a rail gun has nothing to do with gravity. Turn it on it's end and instead of accelerating horizontally, it goes up. Those same magnets keep the cable and car from coming in direct contact. No friction.

No, I wasn't thinking of that. I was thinking more along the lines of a plucked string. All manner of things will pluck it. As long as they aren't near a resonant frequency they will die out, but they still have an offset. And you know that is many feet in the case of the tides. As to the jet stream at eight miles above the surface, I'd expect it could bend the cable a hundred feet off a straight line. Good enough pluck.

Again, I remind you that the cable is 40 000 km long. Equating that to a guitar string, which is around 40 inches, you would be plucking less than 1 millimeter from the end. I play guitar: you would have to pluck it pretty darn hard to get any sound out of it that close to the end.

Cable can't weigh too much. It has to be strung in the first place and in one piece as there is nothing to attach an end to while you splice the next one on.

Since, presumably, it will be lowered from orbital height of 40 000 km it won't 'weigh' anything at all. But it will still have one heck of a lot of mass.

Even if it is, say, 1 m in diameter (and I can't imagine technology that could make it much less than that) it still will have a volume almost 32 million cubic meters. Let's postulate a pie-in-the-sky tech that can build this with a specific density of 0.1 (1/10 that of water), we are talking about a total mass of 3.2 million tonnes, 3.197 million tonnes of it above the atmosphere. Remember, we are talking mass, not weight. The weight doesn't matter, the mass does.

@ John McLeod VII. Well, we are imagining all kinds of as-yet impossible technology here. Presumably we can figure some way of building in 300 atmospheres pressure. :)

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Pure mathematics is, in its way, the poetry of logical ideas.

Albert Einstein

It works horizontally because gravity pushes the cars down close to the magnetic track (rail gun). In vertical mode there is nothing to keep the cars next to the track unless you hang on to the track.

The cable runs through the centre of the car. The car is propelled upwards by the linear motor of which the car and cable are both parts. The horizontal motion of a rail gun has nothing to do with gravity. Turn it on it's end and instead of accelerating horizontally, it goes up. Those same magnets keep the cable and car from coming in direct contact. No friction.

I suggest you remember the direction of the magnetic field of a conductor carrying current. I suggest you figure out where the return current is going to flow. While you are at it, figure out how many amps of current your conductor can carry. Or should I say what the voltage difference is going to be for a 80,000 km round trip. We don't have room temperature super conductors yet and they aren't likely to be physically strong enough.

Oh, might also want to think about that 40,000 km long conductor and what may be impinged upon it from the magnetic fields that exist, such as the earth's and the sun's.

No, I wasn't thinking of that. I was thinking more along the lines of a plucked string. All manner of things will pluck it. As long as they aren't near a resonant frequency they will die out, but they still have an offset. And you know that is many feet in the case of the tides. As to the jet stream at eight miles above the surface, I'd expect it could bend the cable a hundred feet off a straight line. Good enough pluck.

Again, I remind you that the cable is 40 000 km long. Equating that to a guitar string, which is around 40 inches, you would be plucking less than 1 millimeter from the end. I play guitar: you would have to pluck it pretty darn hard to get any sound out of it that close to the end.

Your guitar string is a cable about a mile in diameter at the same scale, try plucking a split spider web strand to get the scale right.

Cable can't weigh too much. It has to be strung in the first place and in one piece as there is nothing to attach an end to while you splice the next one on.

Since, presumably, it will be lowered from orbital height of 40 000 km it won't 'weigh' anything at all. But it will still have one heck of a lot of mass.

Only about 1 mm of that 40,000 km cable will be at zero g. Every other bit of it will not be at orbital speed, at the altitude it is at so it will not be in zero g, hence it has weight. If it was weightless we could build today out of ordinary stuff.

In any case I meant the weight/mass of the material now sitting on the earth's surface that has to be hefted into geosynchronous orbit to either build it in place, or reel out a ground built cable.

Even if it is, say, 1 m in diameter (and I can't imagine technology that could make it much less than that) it still will have a volume almost 32 million cubic meters. Let's postulate a pie-in-the-sky tech that can build this with a specific density of 0.1 (1/10 that of water), we are talking about a total mass of 3.2 million tonnes, 3.197 million tonnes of it above the atmosphere. Remember, we are talking mass, not weight. The weight doesn't matter, the mass does.

@ John McLeod VII. Well, we are imagining all kinds of as-yet impossible technology here. Presumably we can figure some way of building in 300 atmospheres pressure. :)

No building there anyway, all you have to do is attach it to the planet. However that should be done on the tallest mountain top on the equator to reduce the mass of the cable, tensile strength needed and the cost of the project.

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you don't need a cable for an elevator to space... please imagine a straw with a vacuum at one end if you put a pea at the other entrance it would suck it through no cable needed....you would need a very strong structure to support the main shaft..

you don't need a cable for an elevator to space... please imagine a straw with a vacuum at one end if you put a pea at the other entrance it would suck it through no cable needed....you would need a very strong structure to support the main shaft..

If that worked, there wouldn't be any atmosphere.

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Then will be forgetin the compensation module the crystal would compensate for both atmospheric phenom

hehe

and we've forgotten that air has weight. sucking up several hundred miles worth of air can get quite heavy.

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In a rich man's house there is no place to spit but his face.
Diogenes Of Sinope

and we've forgotten that air has weight. sucking up several hundred miles worth of air can get quite heavy.

Not really, just around 15 pounds for a square inch column. What you have forgotten is you can't suck it up from the top. You have to push it from the bottom.

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and we've forgotten that air has weight. sucking up several hundred miles worth of air can get quite heavy.

Not really, just around 15 pounds for a square inch column. What you have forgotten is you can't suck it up from the top. You have to push it from the bottom.

You'd also have to have a tube that wouldnt collapse under vacuum, get crushed by the atmosphere or collapse under its own weight. The space elevator is assuming hyper thing carbon fiber or other futuristic material. current materials would be impossible to produce and transport to space for use.

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In a rich man's house there is no place to spit but his face.
Diogenes Of Sinope

and we've forgotten that air has weight. sucking up several hundred miles worth of air can get quite heavy.

Not really, just around 15 pounds for a square inch column. What you have forgotten is you can't suck it up from the top. You have to push it from the bottom.

You'd also have to have a tube that wouldnt collapse under vacuum, get crushed by the atmosphere or collapse under its own weight. The space elevator is assuming hyper thing carbon fiber or other futuristic material. current materials would be impossible to produce and transport to space for use.

You simply don't get it do you?

If you put your tube up, until you do something, the pressure inside the tube matches the pressure outside the tube. That means vacuum at the top, and 15 pounds at the bottom. Put your thing in the tube and nothing happens despite the vacuum of space sucking on the open top end.

It doesn't matter of the wall of the tube is there or not. We aren't sucked off the earth.

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and we've forgotten that air has weight. sucking up several hundred miles worth of air can get quite heavy.

Not really, just around 15 pounds for a square inch column. What you have forgotten is you can't suck it up from the top. You have to push it from the bottom.

You'd also have to have a tube that wouldnt collapse under vacuum, get crushed by the atmosphere or collapse under its own weight. The space elevator is assuming hyper thing carbon fiber or other futuristic material. current materials would be impossible to produce and transport to space for use.

You simply don't get it do you?

If you put your tube up, until you do something, the pressure inside the tube matches the pressure outside the tube. That means vacuum at the top, and 15 pounds at the bottom. Put your thing in the tube and nothing happens despite the vacuum of space sucking on the open top end.

It doesn't matter of the wall of the tube is there or not. We aren't sucked off the earth.

you still don't explain how the tube is supported much less how it stays in one place. the tube would have to be rigid otherwise the inside would not be circular and prevent objects from making a seal in the tube. a stiff tube made of carbon fiber would be ideal but like anything it will sway with the wind which again is going to flex the tube. I would also like to know what happens with all the air that gets delivered to space and how retrieval of objects sent in the tube would be recovered since they'd be subject to the vacuum and freezing temperatures of space.

I remember that for a space elevator to be functional it must be in geo sycronous orbit. Not LEO. anything less and the elevator would slowly pulled back into earth. So this tube would have to be more than 26,000 miles away from earth. This is highly unlikely to occur

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In a rich man's house there is no place to spit but his face.
Diogenes Of Sinope

Here is a story about NASA awarding a space elevator prize....

900000 Nasa Prize

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Official Abuser of Boinc Buttons...
And no good credit hound!

you still don't explain how the tube is supported much less how it stays in one place.

I thought you were the one arguing for the vacuum sucks it up tube.

Sorry I misunderstood.

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nope that wasnt me. and thats a helluva lot of suction if its going to lift something 26000 miles away without collapsing the tube.

I'd rather thing that a capsule that surrounds a cable would be perfect for climbing...

My main problem with the whole idea is the cable is 26,000 miles long has to be metered out from space so someone is going to have to carry 26,000 miles of cable into space. that seems like an enormous project on top of having a spacestation built to accommodate all the folks that would eventually be needed to build the station and house those climbing the cable afterward.
I'd say we are at least a couple centuries away from ever getting started on anything like this.

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In a rich man's house there is no place to spit but his face.
Diogenes Of Sinope

Speaking of space elevators that is only the first step.

http://www.giwersworld.org/artiii/elevat23.jpg

I did this many years ago while still learning povray. Sort of sentimental about it so I never improved it.

BTW: That is the moon to the same scale without background to make it look bigger than it really is.

Basically the inner ring is the 1/2g living space while the Earth is having its Fountains of Earth ice age. The outer ring is the 0g point and the extensions are where ships arrive and depart to do the same for the energetics inbound and outbound as it does from the surface to orbit.

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Unvarnished
Haaretz
Jerusalem Post
The origin of the Yahweh Cult

Speaking of space elevators that is only the first step.

http://www.giwersworld.org/artiii/elevat23.jpg

I did this many years ago while still learning povray. Sort of sentimental about it so I never improved it.

BTW: That is the moon to the same scale without background to make it look bigger than it really is.

Basically the inner ring is the 1/2g living space while the Earth is having its Fountains of Earth ice age. The outer ring is the 0g point and the extensions are where ships arrive and depart to do the same for the energetics inbound and outbound as it does from the surface to orbit.

Made your link active

Reminds me of a novel I read years ago about building a similar structure around a star. I think it was called 'Ringworld' but I don't remember the author.

Anyway, cool idea. Pretty big engineering project, tho. :P

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Pure mathematics is, in its way, the poetry of logical ideas.

Albert Einstein

Speaking of space elevators that is only the first step.

http://www.giwersworld.org/artiii/elevat23.jpg

I did this many years ago while still learning povray. Sort of sentimental about it so I never improved it.

BTW: That is the moon to the same scale without background to make it look bigger than it really is.

Basically the inner ring is the 1/2g living space while the Earth is having its Fountains of Earth ice age. The outer ring is the 0g point and the extensions are where ships arrive and depart to do the same for the energetics inbound and outbound as it does from the surface to orbit.

Made your link active

Reminds me of a novel I read years ago about building a similar structure around a star. I think it was called 'Ringworld' but I don't remember the author.

Anyway, cool idea. Pretty big engineering project, tho. :P

Ringworld and several sequels all equally good by Larry Niven.

To General Washington the suspension bridge across the Delaware is an impossible engineering project.

After the elevators are up the building materials come most all from space rather than up from the Earth's gravity well. Parts are built as needed. Solar cells have a theoretical 2kW/m^2 so a mere square kilometer of them produces more than enough power to make more square km of them. Unlike Earthside they just to the north and south of the living area and don't have any real estate cost involved.

When I grow up I want to work on the mass balancing system as things move up and down the elevators and across the living area. That's what I get for being born a century too soon.

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Unvarnished
Haaretz
Jerusalem Post
The origin of the Yahweh Cult