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I think the argument was that we don't have materials that are stong enough and light enough and cheap enough at the same time.
IIRC Specifically there are no materials we can currently produce (at that scale) which would be capable of supporting the weight of the cable alone. Let alone cars that ride along it.
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There are various simulations of what may happen. Here is one that demonstrates what may happen if the cable breaks at various points. http://gassend.net/spaceelevator/breaks/ In summary, if the cable breaks at the base, the elevator will fly harmlessly into space. If it breaks at the counterweight, a large portion of the cable (several thousand miles long) will collide with the Earth’s equator.
The piece that falls to Earth ends up wrapping faster and faster, this causes centrifugal force on the tip, increasing the tension in the ribbon. Often the ribbon breaks on its way down and some fragments go flying out of Earth's gravity well. I didn't expect this at all. The space elevator would become a space whip. I wonder whether this has a use case, like getting hardened unmanned space probes to speeds required…
The cars would travel at up to 200kph and arrive at the space station eight days after departure from Earth. These early cable experiments are important, but someone should also be working on the composing an 8 day Elevator Muzak score that won't drive you insane.
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I don't doubt there's a market for that service.
Yes, but it's a completely different market from folks desiring a space elevator. Also, it makes the need for muzak nonexistant because all your passengers are dead and can't hear it anyway. Seems to me that defeats the purpose of trying to time the trip to coincide with the length of a particular song.
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Yes, but it's a completely different market from folks desiring a space elevator. Also, it makes the need for muzak nonexistant because all your passengers are dead and can't hear it anyway. Seems to me that defeats the purpose of trying to time the trip to coincide with the length of a particular song.
It seems to me that you missed the joke…
It just wasn't really that good.
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That trip would only take an hour, but I don't think you could build a cable and drive system capable of operating at 18 km/s.
Just for a bit of fun perspective, that’s 7 km/s faster than reentry velocity! Even if you felt like dealing with the heat, it would cost an ungodly amount of energy which kind of defeats the point of an elevator. On the other hand, you could ignore radiation shielding if the trip is short enough? Not worth the trade off I think.
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Or you just build the cable out beyond geosynchronous orbit. The further out your counterweight mass is, the more force it exerts, so, AIUI, the most mass-efficient way to do it is an extension of the cable.
The problem is how you keep the tether from dragging behind the orbit when you do that. Space elevators require a fairly delicate balancing act to keep the mass directly over the base of the elevator, otherwise they turn into giant slings.
None of this should be construed as an endorsement of space elevators, though. They will never happen on Earth as it exists now. Over and above the material science, you have to clean out LEO of all satellites before you even start construction. It’s just a really dumb idea all around.
The cars would travel at up to 200kph and arrive at the space station eight days after departure from Earth. These early cable experiments are important, but someone should also be working on the composing an 8 day Elevator Muzak score that won't drive you insane.
Stairway to Heaven is about 8 minutes long, so they better work hard on speeding the elevator up to match that.
3.4x10^7/(500)^2 = a m/sec2
For an 8min20sec flip time. 20+g if you really want the 8min.
i remember reading here on HN someone explaining why space elevators are not possible. I can't recall why, but he/she had very convincing arguments. Anyone here remember that thread and can link it back here? Thanks
Once you figure out how to make them en masse, now you have to figure out how to secure the strands into a bundle.
Less of a challenge than warp drive, but still...quite hard.