Space Elevator conference in Seattle (1 Viewer)

[Jared_B]

Looks like this Space Elevator idea is gaining some interest. Here is a link to the web site for the '02 conference. Maybe someone who understands how this thing works can explain it in simple-minded terms for people like me!
I've heard that the technology is supposed to be 50 years out, but the supporters are saying more like 15 years before they can get it working. Thoughts?

 

[Michael*K]

There was a cover story on it in Popular Mechanics a month or two ago that explained it in pretty good laymen's terms.

 

[Edwin-S]

There is a pretty good explanation of the basic operation of a space elevator in the link you posted. It would operate like any other elevator. The main obstacle to the exploitation of space is the cost of lifting mass quantities of material from earth to low earth orbit. Rocket launches are expensive and the amount of material that can be lifted at one time is relatively miniscule. The cost leaves the exploitation of space mostly in the scientific realm.

If the space elevator actually becomes feasibly doable, which is what the article you posted indicates, then the cost of lifting payloads from earth to orbit could fall, from thousands of dollars per pound/kilogram, to several hundred dollars per pound/kilogram or even lower, depending on the lifting capacity of the elevator. It would make the commercial exploitation of space economically feasible. The country or entity that actually succeeds in building something like it would probably have a technological and economic lead for decades. The impact of a space elevator on the economic, environmental and geo-political fronts could potentially be huge because who ever controlled it would essentially control the development of the space based economy. I think the only thing that would compete with it for impact on humanity as a whole would be the discovery of a cheap, safe (if that is really possible) form of energy that would render fossil fuels obsolete.

 

[Danny R]

As mentioned above, the reason you want to make a space elevator is to counter that bitch of a force that keeps us slaves to this planet: gravity. Because of gravity, it takes huge rockets just to throw up a small payload. Once an elevator is put into place, you have a much easier time hauling cargo up. This is either because you can counterbalance upcoming loads with downmoving ones (by mining your anchor asteroid), or just use traditional mechanical devices to simply climb the cable. If the cable is electrified for instance, you don't have to haul your fuel with you, which is why rockets are so expensive and wasteful. (to get a payload higher, you need more fuel, which weighs more, which requires more fuel, etc)

Of course the biggest problem with any sort of space elevator is finding a material strong enough to hold even its own weight at that distance, let alone the other stresses caused by wind sheer, micrometeorite strike, buckling and twisting and even just the weight of cargo.

If you want to build something more substantial, like a traditional tower, then you have even more weight needing to be supported on the ground. Given that we've yet to build a skyskraper even close to one mile high, this approach is probably not the best.

Alternative space elevators might be in much lower orbit, and have rotating cables that periodically touch down at many points on the earth. The advantage of course is that you don't need nearly as long of a cable and also aren't limiting yourself to a position along the equator. However with this form of elevator you would definately need to balance the upgoing material with downgoing material, or you would halt the spin.

 

[Edwin-S]

I made a bit of an error when I said it would operate like any other elevator. The basic function would be the same, however, the cable remains stationary and the cars would climb and descend by traction on the cable. Had to correct myself, even though it basically goes without saying that the cable would have to be stationary.

 

[Chuck C]

how bout some flying cars first!?

 

[Danny R]

even though it basically goes without saying that the cable would have to be stationary.

Bite your tongue. It never goes without saying. Think outside the box.

As I mentioned in my rotating space elevator, the cables swing down, hook onto the payload, and swing back up carrying the payload with it. One giant ferris wheel.

And there is no reason why a super monofilament cable couldn't be hooked to a pully and function as a normal elevator would (assuming we could construct such a thing)

 

[Peter McDonald]

That would be cool to have a ferris wheel a few miles high
Peter

 

[Francois Caron]

If you want to read a story involving the construction of a space elevator, read "The Fountains Of Paradise" by Arthur C. Clarke, originally released in 1979.