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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."
Yeah but who wants to listen to that god awful music?
If magic pixie dust were invented it would be such a waste to spend all this money on conventional boosters. Come on NASA! Drop what's known to work and concentrate on the pixie dust formula.
But, I don't remember ever hearing that we actually have the technology to produce enough carbon nanotube material to actually build a prototype device of some sort let alone a cable spanning to LEO. I realize it's 14 years away.. but there's no guarentee we will actually have the capacity by that time. As far as I'm concerned we're better off building what can actually be finished come 2020 let alone tested and on our way to the moon.. again..
Sigh. Ya know, we could build a structure to space with todays (hell, 20+ year old) technology if we wanted. The Launch Loop concept was published 20 years ago and is viable today. It costs less than a space elevator is predicted to cost and, unlike the space elevator, can be built from the ground up instead of from orbit down. So yeah, please stop saying stuff like: once we have strong carbon nanotube fibres we'll have a space elevator two weeks later. It doesn't work like that. The majority of studies that remain to be done to make the Launch Loop a reality are much the same as the many studies that still need to be done to make the space elevator a reality. Someone has got to finance those studies and unless you can get PhD students to do it on government funding that means you've got to pour money into a hole that might never fill up.
How we know is more important than what we know.
I like the idea of the space elevator . . . but won't it be a prime target for terrorist attacks? I mean, if I was a terrorist, it'd be the first place I'd direct my hijacked pla . . . moment, there's a knock at my door.
The August issue of IEEE Spectrum also had a story about the space elevator. This article is available online here. Not knowing much about the space elevator, I found this article very informative.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Maybe i am a bit out of touch (although i doubt it, being physicist and seeing people who actively work in the nanoparticle research and astrophysics department everyday), but i think this is all such a bullshit.
Space elevator this, space elevator that. Its just a pie-in-the-sky dream, and will be for the next century(ies). We dont have bucktubes "thick as a hair but strong enough to lift a car".
We dont even have them a meter long and strong enough to lift an apple.
And even than, it took millenia to get from iron->steel->a few km steel wire for bridges/ect.
Singularity this or that, you shouldnt expect something like the support of the golden gate bridge via nanotube based cables the next decade(s)
(not even mentioning the hurdles of a structure 30.000km+ long and sturdy enough to support the lifting vehicle and atmospheric conditions).
Also, the best we ever did concerning long wires and space was a test a few years ago, where they even failed to unwind a 300km, unstained wire in free space.
Not to mention that to get the whole framework running you need an efficent way of getting material and people up there to begin with... without a shuttle mk2 or 3 or 4 or 5 there is not even a point to start the whole shit.
But it seems nowaydays you only need to throw some buzzwords like "nanotubes" into the crowed and they would believe you even if you promised them portable teleporters...
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
No, it hasn't.
The space elevator will become viable when someone creates a strand of carbon nanotube and lifts a car with it.
If you want to make me believe that a carbon nanotube space elevator is a viable proposition, demostrate that you can build a carbon nanotube suspension bridge first.
Doesn't have to be a replacement for the Brooklyn Bridge or the Golden Gate. A footpath over a creek at your local engineering college will do.
Until then, you're as likely to go into orbit on a space elevator's as you are on a matter/antimatter drive: as in "not at all".
The LiftPort Group of companies working towards a space-elevator are making a great deal of progress. Slashdot reported on the faa approval of their high altitude tests, for example. See here and here for more LiftPort specific information. Check here and here here for several reports concerning the viability of the elevator -- be sure to check the NIAC pdf. Blaise Gassend has a great collection of information. Finally, though carbon nanotubes are still in their infancy (its been a little around ten years since they were discovered) - their theoretical tensile strengths are perfect for application in a space elevator construction. This recent development spells a rosy future, and many innovations yet to come.
...one giant leap for the first wise ass to press all the buttons (Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere...) and piss off the other astronauts.
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-- See?
It's not that easy, the space elevator is supposed to work because it has (will have) a counterweight on geosynchronous orbit that keeps the elevator in place. The space elevator is more like a string tied to a balloon than a wooden stick.
Led Zeppelin's "Stairway to Heaven"! :)
Launch Loop presentation and Space Elevator presentation .
For large projects to be realized, they either have to be of decisive strategic/military value during war (Manhattan project), or they have to completely capture the hearts of the citizens that are supposed to pay for it all (Apollo Project, "before this decade is out..."). Clearly, for the Space Elevator, the latter is the case. I, for one, have not heard of Launch Loop before, and the dry PDFs and text files that are Google's #1 on the term didn't really invite me to care about it. The Space Elevator, on the other hand, has been part of the popular culture for decades, and has recently surged astronomically (no pun intended) in terms of mainstream recognition.
Just as it would have been more affordable and scientifically more valuable to gradually conquer space and ultimately the moon (i.e. with manned space stations and a launch from space etc.), it was the extreme appeal of the "moon shot", the giant leap that won the favor over the more economical approach.
The grass is always greener on the other side of the light cone.
Structural engineering issues aside, the big problem with space elevators is the junk in low earth orbit. If a 200 kg object hits the structure at a relative velocity of 15,000 MPH, it will release energy equivalent to one ton of TNT.
If you simply want to get cheap payload into orbit this decade using materials that are NOT theoretical, find a way to get funding to the blimp-to-orbit people at JP Aerospace.
Lots of things wrong with the Space Elevator concept... it breaking could kill a lot of people... but the dealkiller is that you can't build a structure with theoretical materials, and it shouldn't take a "rocket scientist" to figure this out.
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A space elevator will be made of carbon fiber nanotubes correct?? What would be the effect on a hurricane hitting the elevator? Can the string be realed in from one end?? Would it be more prudent to build this in a place far away from a coastline??
negliable if built correctly. The local winds wouldn't have enough kinetic force to move the cable much.
"There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy."
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.
Actually, the design for one of the ribbons was so thin and wide that the wind resistance alone meant that it fell at about the speed of a cardboard box.
See http://www.elevator2010.org/site/primer.html and http://www.liftport.com/faq2.php#science2 for starters, Google for more.
What really makes sense is an infrastructure that makes getting people and payloads in particular to and from space cheap and reliable, even ordinary. The only chance for that right now is a space elevator.
You have a 3% chance of death flying on a space shuttle. That's an incredibly poor record, and incredibly expensive.
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Basically what we have is a difference of attitude. I see "we have the engineering figured out for using 65 GPa ribbons for a space elevator, and we can produce material now that could almost theoretically have that strength, and in theory we could produce materials almost twice as strong" and I think, this is something that needs research. I am not claiming that 10 years and $100 billion will build a space elevator - I'm claiming that it could put us in a position to know how to build a space elevator, so getting the real funding becomes politically feasible.
You see the same statements, and throw up your hands saying we can't do it. Your arguments that we can't do it are pretty damn weak...
So your position is that we could almost do it with the materials we have now, on a 15 year old technology, if we had the right compositing process, but that it's ludicrous to think that we could actually do it with 10 more years of research focused on improving strength of individual tubes and processes for producing ribbons?
Comparing this to alchemists' dreams of lead to gold is beyond laughable. Assuming that you know more than the researchers dedicating themselves to this research is ridiculous. Assuming science and engineering will go backward rather than forward is demonstrably false. Asserting a strawman argument about bond strength is a red herring. And repeated commands to "deal" (by which you mean adopt your pessimist philosophy) are obnoxious.