bubspeed wrote:
I have read a few books that debated whether the elevators were even possible. Something to do with the mass of the string going to infinity as the elevator went up. They mentioned Carbon nanotubes as a possibility but I haven't heard much of anything since.
I would hate to be in the way of the line if it snaps. 30 miles of cable falling down would make one heck of a mess.
For a long and amazing description of a space elevator falling back down onto a planet (It winds up wrapped around the equator about 3 times) try Red Mars, Blue Mars, Green Mars by Kim Stanley Robinson.
Yodabunny, I don't remember all the physics of it, But the idea is to have the elevator supporting it's entire weight in orbit. There is no actual physical connection to the Earth, it's bottom end just hovers a few meters off the ground. (Within a sleeve.) Also, I think the lifts going up and down are meant to be counterbalanced for the most part, the momentum of the falling lifts helping to propel the rising lifts. There's a few variations on space elevators and skyhooks.
Yes, it would wind up being ridiculously long in length, in order to be able to suspend itself. It would also be a seriously LONG term and high-tech project. But if done, in theory it would make getting people and some materials ridiculously more easy to get out of the Earth's gravity well than they are now.