If made out of carbon one foot in diameter, 18,193,470 tons. I suspect that carbon nanotube cable 1 foot in diameter couldn't even come close to supporting 18 million tons plus other stresses.
Seems like something that massive would be affected by lunar cycles.
would be massively heavy
If made out of carbon one foot in diameter, 18,193,470 tons. I suspect that carbon nanotube cable 1 foot in diameter couldn’t even come close to supporting 18 million tons plus other stresses.
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carbon nanotubes are extremely strong small and light.
IIRC, carbon nanotubes are hollow. Thus, a cable made up of them would not "weigh" as much as a solid length of either diamond or graphite. I don't know how big a cable would be necessary to support the load. Perhaps it would not need to be that large.
Also, the cable would weigh less as you ascended because of the centrifugal force acting on it. At geosynchronous altitude it would be "weightless." Above that altitude, it would actually pull "up" on the cable.
Your point may still be valid, but your calculation is not.