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scott712
2003-Jul-28, 06:48 AM
How to Fall Up. Seriously!

A Carbon nanotube cable of uniform thickness and 144,000 KMs long will be
self-balancing without a counterweight. If you make it a little longer, then the cable will actually be out of balance pulling up. Then you can attach more, ever-widening cable to the bottom and it will be pulled up into Space powered by the Earth's rotation.

This is my entire point you only need to put about five tonnes
into orbit by rocket. The rest just falls up!

Space Cable afficionados will be quick to point out that Space Cables are
"supposed" to be thickest at 35,800 Kms distance from the Earth where the tension is greatest on the cable. However. Carbon nanotubes are three times
stronger than they have to be to support their own weight with a uniform cross-section. This means they can actually be more than three times thicker at the base than at geosynch at 35,800 Kms.

Wm. Scott Smith
Spokane

scott712
2003-Jul-28, 06:53 AM
Billions of Tonnes Falling Up

We're talking about billions of tonnes of Space Cable rising into Space powered by the Earth's rotation. We're talking about doing for Space what the railroads did for the American Far West, with a lot less blood sweat and tears.

megaquark
2003-Aug-23, 01:03 AM
One problem. Once it was no longer attached to the earth, it would fall up, then what?
Also, if it stays attached and you keep adding on, at some point, the earth would no longer be turning the cable, instead, the cable would be rotating the earth, is this right? At some point you would have to cut it loose. given the fact that the mass of the earth would be several orders of magnitude higher than that of the cable, that cable would eventually fall back to earth. What then?
Oh, one more thing. I am not sure, but I think that the Earth isn;t simply swinging this cable. The other end has to be accelerated to orbital velocity. The problem is that the further you go away from the earth, the faster the end has to travel to maintain geosynchronus orbit. If you were constantly adding on to the bottom, you would have to constantly accellerate the top. If at any time this failed, it would slow and would end up wrapping itself around the earth..........Big time ouchy!
Any experst on physics out there that can contribute?

ferg.c.
2004-Dec-14, 09:58 AM
Well, this is an interesting idea. Lets say we tie a rope to the moon which leads down to the Earth and somehow we manage to synchronise the Earth to have a day that lasts four weeks so that the moon is always above the same point. Now we arrange so that the tension in the rope is zero and that means that any force applied to the rope from the moon above its angular force which is equal to the acceleration of the gravity between the two bodies times the mass of the moon will cause the rope to pull away from the earth (causing the lift effect). If we add a length to the rope at this end in the hope that, as it is passed up to the moon it will increase the mass at the lunar end of our experiment we are doomed because the other end of the rope becomes proportionally massive and we always get a neutral point (in this case 81% of the distance to the Moon) about which the rope can do nothing. There is no lift effect and you just spent a lot of "money for old rope" so to speak!
Ferg :)