Jouni Valkonen <[email protected]> wrote: I think that the biggest problem with Space Elevator is that it is too > slow. I takes quite a lot of time to climb into geosynchronous orbit.
Edwards and Westling (p. 49) say the first generation climbers should go 200 km/h. They have to go 100,000 km to reach the counterweight. But to get to the terminal at 36,000 km that would take 7.5 days. That would be tedious for people but not an issue for freight. I expect much faster climbers would soon be possible, reducing the trip to ~3 days, which is less time than it used to cross the U.S. by train. It is not a big deal. The weight of the initial ribbon would be 40 tons. Two rockets could lift it, in two sections. > I think that fast climbing is too demanding for the materials . . . That does not seem to be issue. E&W do not mention it. The only materials issue is space junk poking holes in the ribbons. Space junk has to be cleaned up, and it could be with a multi-ribbon space elevator. You would have to devote one ribbon to an interceptor craft for several months. > and slow is just too slow in order to get much cargo during one year. It > takes week or so for one way trip. That makes no sense. It takes a lot more than a week to get cargo from China to the U.S. and Europe but we send millions of tons. The duration does not matter. Once we have one ribbon, and people at the space station, deploying additional ribbons would cost practically nothing. You can make hundreds of them. > I think that it is just a matter of engineering to get enough power for > Maglev acceleration. > A maglev space elevator could reach 36,000 in a day or two. It would require a massive tower made of stiff material. The original ribbon elevator is made of cloth-like material, like a newspaper. If there were ~100 of them deployed (4,000 tons of material) we could ship hundreds of thousands of tons and thousands of people into space. We could mine asteroids for materials to build a rigid tower and space elevators for the Moon, Mars, and other planets. - Jed
