Posted on 08/19/2002 8:09:11 PM PDT by Brett66
Yes, you have to calculate the total energy, but it's still just a few dollars per pound.
How do you lift the string and counterweight in the first place? Why would you even need a string and counter weight?
You lift it with rockets, though the counterweight could be an asteroid that you corral, or perhaps a lump of lunar material.
You need the string to provide a basic structure for the elevator, just as you need to throw a line over a gorge to start building a suspension bridge. The counterweight is to keep the system in tension. Objects below geosynchronous altitude will have positive weight (they'll want to fall down) and objects above will have negative weight (they'll want to "fall" up).
You're right it wont get around physics. The major advantage to having a space elevator ? Raw electricity can get payloads into orbit.
Stick a few reactors around this place and you will never need the expense of chemical rocket engines to get in and out of the gravity well.
Nonsense. It will still be at least an order of magnitude lower cost than any imaginable rocket.
Won't do it. You have to make that electricity and then make motion out of it.
That's why they invented something called an electric motor. Of course the materials strength at this time is far too weak to do the job but if materials science can get diamondoid type fibres then it might be up to the job.
That the orbital velocities are different along the length of it are different is well known which is why the tensile strength will have to be enough to over come that. Running the cable down from geosynchronous orbit with a counterbalancing weight at the end should help relieve some of the stresses.
Do some math, figure out how much it has to weigh and what is the best way to get up. You'll quickly be as discouraged as those of us that have already done the math.
I don't have the numbers for it but I'm sure there were guys like you saying that we'd never have the proper power to weight ratio to build planes. We went from powered flight to the moon in 3 generations. We'll eventually figure this megaengineering project out. True this is not a valid logical answer but damn ... no one ever accomplished much (other than project scope) by saying what we can't do.
Of course if we went to Orion style atomic propulsion a lot of the engineering difficulties become moot.
We know what electricity costs. We know what the energy requirements to put an object up to that altitude and that velocity are.
Essential none of this space string is in orbit, all of it travels at the wrong speed for orbit. For instance, at the Space Station altitude, it's doing a little over 1000 mph. To be in orbit you need altitude, velocity and direction. A lot of people need to get their math inline with their dreams.
Do some math, figure out how much it has to weigh and what is the best way to get up. You'll quickly be as discouraged as those of us that have already done the math.
My degrees are in engineering science and applied mathematics. I've done the math. I've published peer-reviewed papers on the subject. You've done nothing to defend your criticism of the concept. You've just pooh-poohed it, with no calculations put forth at all.
And your comments above indicate your fundamental ignorance of the concept.
Of course it's not in orbit, and no one has claimed that it is, so you're attacking a strawman.
That's the point. Nothing that is attached to the earth can be in orbit. Regardless, it's a structure that can provide transportation into space at the raw costs of the energy required to do so, by its nature. The only place, though, that you can let go of it and be in a circular orbit, is at geosynchronous altitude. But that's OK. You're in space, and you're halfway to anywhere.
In the mean time, the stock is probably very cheap, sounds you should invest. This will be operational in just 10 years, right?
No, I think that it would be a very foolish investment. I already said that it's not practical, and it's unlikely to happen for decades, if ever. I'm just disagreeing about why it isn't, and it's not because the costs or physics don't work.
This statement is not clear???
The material is already invented and produced in large quantities. All you need are fibers from Rosie O'Donuts Spandex pants. Anything that can hold all that can be used a cable to space.
used as a cable..
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