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Thoughts on the Space Elevator
Keith Curtis writes to tell us that Glenn Reynolds, of Instapundit fame, has posted his thoughts on why NASA should be building a space elevator instead or their current plans. Keith has also posted his throughts from an engineer's perspective (although admittadly still not a rocket scientist). "The challenges are many, but it has been a viable option since carbon nanotubes, structures so strong that one the width of a human hair could lift a car, were invented. A space elevator could be between 10 and 2000 times cheaper than conventional technology and will force NASA to change just about everything they do. Hopefully one day that bureaucracy will wake up and realize it."
Why isn't this stuff being used as an emergency rescue material, to make ladders that can be telescoped up to the 30th floor of skyscrapers? Surely there could be less ambitious projects for this material before committing to something that has to deal with the extreme stresses and temperatures in space and the upper atmosphere?
Make a model of a space ladder/elevator, by designing something that can save lives here at home, and it will take off like a rocket in the public's eye, pardon the pun.
Saskboy's blog is good. 9 out of 10 dentists agree.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Actually, it's more than Geosynchronous - the centre of gravity needs to be at GS (or near it, the fact that it's joined to the ground might have an effect), so it has to go past it by an amount depending on the mass of the counterweight.
Parent is not a troll. He's trying to make a point. The Space Elevator is a untested and unproven technology. Like all unproven technologies, there are bound to be hidden costs, hidden delays, and hidden engineering problems.
NASA is taking the correct approach. They are building something that they *know* works first. They can then work out the pixie dust^H^H space elevator next.
Javascript + Nintendo DSi = DSiCade
I agree completely. We've done the moon thing, and have tons of cool rocks. Why do it again? What will that $100 billion do for us that hasn't been done before? It would be much better spent researching and developing something like a 36,000-km nanotube ribbon than going up and getting more rocks. Even if the ribbon proves unproduceable, we would be investing in basic research, and not simply lining the pockets of the US space industry, ie Boeing, Lockheed-Martin, etc. to do something that has been done before.
There isn't even really that much basic materials work that needs to be done. They just need to get the composite percentage up (iirc) from around 10% to around 50%. I think the success of carbon nanotube companies and SpaceShipOne suggests the best way to do this is for NASA to offer large monetary rewards, perhaps in the range of $10 - $100M, for producing a workable cable and climber power source. My understanding is those two things are the major engineering hurdles right now. Currently there is a NASA-sponsored climber competition, which I believe has a 400K reward.
think sept. 11
Bullshit, 9/11 happened because it was a one off, it's unlikely to happen again because who is going to believe highjackers who tell you that you'll be all right if you cooperate and don't resist. That's not likely to happen again. Also you can set up a no-fly zone for 100 miles or so around the elevator and enforce it with a couple of Patriot missile batteries for distance work and Vulcan cannons for close in work. We have bunches and bunches of people in all four services thinking about ways of improving "if it flies, it dies" technology and they'd love a chance to try out their stuff.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
On the side where the ribbon comes down you generate electricity which you transfer over to the other side of the structure where the ribbon is going up. That's how you balance the structure without expending a whole lot of energy. The author has been studying this technology for 20 years, along with a lot of other people.. it's solid. There have been scale models built, lots of them.
How we know is more important than what we know.
I am a physicist who works in nanotechnology, carbon nanotubes even. I guess I would be one of those physicists who looks through a microscope, and not a telescope. I'm really not sure if you were trying to make a point with that line, but it seems a funny thing to say in a discussion about nanotechnology.
The things which are coming will blow your mind, but a space elevator with nanotubes isn't happening any time soon, despite what any historians may tell you. Contrary to what the "article" suggests, NASA IS working on this technology. They have spent a huge amount of money trying to get someone to grow a rope of continuous nanotubes just 1 meter long. Some of the best people in the world at nanotube growth are working on this (and have been working on this), and it will take a few years yet before they actually do it. Consider that two nanotubes tied (welded, bound, woven...) together are nowhere near as strong as one continuous nanotube. Consider also that nanotubes grow at around 10^-5 meters/s. Geosynchronous orbit is about 3.6*10^7 meters away. Here, really is the fundamental problem if we're going to try to grow a space elevator. If you go through the math, it would take about 10^5 years with today's technology, which makes the prediction of centuries very optimistic. I think it will take less than centuries (as in, I think we will find new growth or welding techniques), but there may be better ways of getting into space.