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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?
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.
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".
...one giant leap for the first wise ass to press all the buttons (Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere...) and piss off the other astronauts.
--I'm so big, my sig has its own sig.
-- See?
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.
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
Given the rates at which prices for storage, processing, and networking were plummeting, a problem that would take eight years to solve today could be solvable in four years two years out, and in two years two years from now. So by putting it off for two years, you'd shave two years off the project.
This may be true in the everyday world of cut-throat competition, but if we call this "optimal" and everybody does it, everybody waits two years, and nobody puts forth the effort to realize the gain in productivity. Leeching off of technology that hasn't been invented yet reaps the benefits of work paid for by whomever goes first. I call it a technologically-oriented game of chicken.
Looking more closely at NASA's past projects, you will find that NASA takes precisely that role - the government puts up huge sums of money on an unproven technology, and the world reaps the benefits years (or decades) later. From the taxpayer's perspective, the only important criterion is whether the indirect reward will pay back the taxpayer for the up-front costs.
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.