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Arthur C. Clarke's idea of a space elevator is coming closer to reality.
Japan starts space elevator experiments
Japan starts space elevator experiments
Yeah, that's why I doubt it will be in my already slightly aged lifetime!It's a great dream, but I believe unfortunately we are still really far from getting something even close to ACC's original
The main issue is, I believe, (and slapping carbon nanotubes as a catch word into it doesn't solve it) is having a cable strong enough. We are still in the realm of science fiction rather than science at the moment.
But I am optimistic, as advances in material science in the coming decades will probably make our current knowledge look as if we were just medieval smithies. So perhaps there will be a breakthrough on some sort of cheap and amazingly strong cable 'stuff'!
Yeah, that's why I doubt it will be in my already slightly aged lifetime!
I think the material for a space elevator needs to be strong under tension not compression. I'm not brilliant at that sort of engineering though so I may be wrong.If the material required will be super strong, why not use them to build very very high rises. Use them almost like a stalk and then build living 'leafs' off them. I may need to think about this.
Depending on your definition of 'exotic' for fizzycists it tends to involve at present undiscovered subatomic particles. But it's true that the assumption that 'nothing could carry its own weight over that length' is somewhat like the argument that 'a chemical rocket would never be able to lift anything to orbit - the fuel would weigh too much to accelerate itself' (overcome by multistage rockets, and since by material science, but it looked like a game stopper at the time) - we could actually build one out of steel, and ajust the taper so the structurally more rugged bit in the lower gravity higher section was only carrying the weight of the thinner bit. It would be a ridiculous size (partly because there I've ignored atmospheric effects and the mass of the ascending capsule, but that's engineering) but the real bummer is the counterweight, either in geostationary or just slightly outside, several hundred thousand tonnes we'd either have to capture from asteroidal mass or lift up from Earth, and the fact that each rising load would minutely slow the rotation (conservation of momentum) so every load going into orbit would have to carry some fuel (or at least reaction mass) to keep the system stable. You wouldn't want that crashing down to Earth - it'd make the dinosaur killer look like a firecracker. It would also make a marvellous target for terrorists - most of my 'beanstalk' stories have the base of the tower in Equador, near Quito - get as much height as you can through mountain, and the thinner the atmosphere the less wind drag. Arthur C. moved Sri Lanka onto the equator (very important, that - I wonder which bit of the equator the Japanese are planning to buy) and added some mountain height - Whichever country is chosen on the equator (and there aren't that many options) is going to make enormous amounts of money, but will need to be politically very stable…Okay, so I can see this thread died long before I arrived here, but I thought it worth adding that a lunar elevator doesn't need exotic materials.
Depending on your definition of 'exotic' for fizzycists it tends to involve at present undiscovered subatomic particles. But it's true that the assumption that 'nothing could carry its own weight over that length' is somewhat like the argument that 'a chemical rocket would never be able to lift anything to orbit - the fuel would weigh too much to accelerate itself' (overcome by multistage rockets, and since by material science, but it looked like a game stopper at the time) - we could actually build one out of steel, and ajust the taper so the structurally more rugged bit in the lower gravity higher section was only carrying the weight of the thinner bit. It would be a ridiculous size (partly because there I've ignored atmospheric effects and the mass of the ascending capsule, but that's engineering) but the real bummer is the counterweight, either in geostationary or just slightly outside, several hundred thousand tonnes we'd either have to capture from asteroidal mass or lift up from Earth, and the fact that each rising load would minutely slow the rotation (conservation of momentum) so every load going into orbit would have to carry some fuel (or at least reaction mass) to keep the system stable. You wouldn't want that crashing down to Earth - it'd make the dinosaur killer look like a firecracker. It would also make a marvellous target for terrorists - most of my 'beanstalk' stories have the base of the tower in Equador, near Quito - get as much height as you can through mountain, and the thinner the atmosphere the less wind drag. Arthur C. moved Sri Lanka onto the equator (very important, that - I wonder which bit of the equator the Japanese are planning to buy) and added some mountain height - Whichever country is chosen on the equator (and there aren't that many options) is going to make enormous amounts of money, but will need to be politically very stable…
'Course, if you're sending in from orbit (down from orbit after the first kilometre or two) washing machines manufactured from asteroid steel, and the same massis coming to Earth as is being lifted away, this will balance, so interplanetary trade can't run on too many surpluses…
An idea I heard mooted a few years ago was to build a tower to the outer atmosphere using inflatables and launch rockets from a platform there. The idea being the fuel needed to get to outer space from that height was much less than from ground level. Don't recall how they intended to get to the platform though. Maybe by balloon?