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Scientist Sees Space Elevator in 15 Years
bofh31337 writes "Scientist Bradley C. Edwards, head of the space elevator project at the Institute for Scientific Research, thinks an elevator that climbs 62,000 miles into space could be operating in 15 years. He pegs the cost at $10 billion, a pittance compared with other space endeavors. 'It's not new physics--nothing new has to be discovered, nothing new has to be invented from scratch,' he says. 'If there are delays in budget or delays in whatever, it could stretch, but 15 years is a realistic estimate for when we could have one up.' NASA already has given more than $500,000 to study the idea, and Congress has earmarked $2.5 million more."
I'm confused. All the technology is there? What about the technology to build carbon nanotubes of sufficient length to actually make the thing? That seems like a rather obviously lacking area which is preventing the construction of an elevator. Perhaps there's been some kind of advance of which I was not aware?
Notice the length of the cable in the article:
"62,000 miles into space"
Notice also that the distance to geosynchonous orbit from sea level is 22240 miles. This means that the cable will go well beyond geosynchonous and will essentially act as its own counterweight, with the center of gravity at the geosynchonous orbit. No asteroid required.. but the cable has to be much much stronger since it would be three times longer and must support its own weight.
So, the statement of "nothing new has to be discovered" I think is incorrect. There is no carbon nanotube that can withstand that tensile force yet. There is also no way of manufacturing carbon nanotubes of this scale.. let along lifting it to orbit intact (or reassembling the different spools in orbit). 15 years is wishful thinking.
-molo
Using your sig line to advertise for friends is lame.
How long do you think the fibers in rope are? I can guarantee that that 50 ft cotton rope does not have 50 ft long fibers. The Vanderwaals forces between the individual fibers, when acting over the whole length of the fibers, holds them together more strongly than the individual carbon-carbon bonds would. There is no reason to explore chemically bonding the tubes.