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Report: Space Elevators Are Feasible
Daniel_Stuckey writes "It's the scourge of futurists everywhere: The space elevator can't seem to shake its image as something that's just ridiculous, laughed off as the stuff of sci-fi novels and overactive imaginations. But there are plenty of scientists who take the idea quite seriously, and they're trying to buck that perception. To that end, a diverse group of experts at the behest of the International Academy of Astronautics completed an impressively thorough study this month on whether building a space elevator is doable. Their resulting report, 'Space Elevators: An Assessment of the Technological Feasibility and the Way Forward,' found that, in a nutshell, such a contraption is both totally feasible and a really smart idea. And they laid out a 300-page roadmap detailing how to make it happen."
For anyone interested in the concept of the space elevator, The Fountains of Paradise (1979 Novel) by Arthur C. Clarke, is a must-read!
It's a very well-written novel that focuses on many of the technical aspects of building a space elevator.
Yeah, the plastic they use for retail packaging should be strong enough.
“He’s not deformed, he’s just drunk!”
As bigjarom mentioned, what's holding us back right now from cheap lift via skyhook is that we haven't quite gotten our carbon nanotube strength up high enough. It's theoretically quite possible.
After that, it's just a question of how do we get enough materials and probably some sort of ribbon* making facility into GEO to actually do the laying. One idea I have is that rather than having to ship all materials to GEO, only to drop it towards the earth, you have a descending constructor that you supply. Though the orbital mechanics of resupplying it can get quite hairy...
*Modern design philosophies has the cable being more of a flat ribbon than circular.
I don't read AC A human right
It's the scourge of futurists everywhere: The space elevator can't seem to shake its image as something that's just ridiculous, laughed off as the stuff of sci-fi novels and overactive imaginations.
I've first heard of space elevators decades ago, and not once have I read or heard anyone saying it's a ridiculous or laughable idea. All I've heard is that it'd be a really great, smart and economical way to access space, if only a strong and light material could be found to prevent the cable from being several miles across in diameter at the base and collapse under its own weight. Where did the story's submitter get that from?
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
One of the things I don't see discussed much is the potential failure modes for such a system.
My wife is a physical oceanographer, and one of the failure modes for instruments deployed on cables from a ship is a 'wuzzle' -- a large tangle of steel cable. Given the nature of the stuff, a length of cable that fits nicely in a spool on deck can twist itself into a knot larger than the ship.
So one thing I'd like to know is what are the potential hazards a couple thousand miles of elevator cable falling to the Earth's surface? Could we end up with tangles miles in diameter?
I think a space elevator is a great idea if it's feasible, provided that in the criteria for "feasible" we include being prepared for the conceivable ways the project could fail.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Problem is that plastic's extremely porous and fragile until it gets to its actual destination. And since the Elevator is effectively always in transit....
I believe the plastic in question is the kind of plastic that semi-permanently entombs your purchase in a chrysalis so touch that you need a diamond tipped super electro buzzsaw or a weapons grade baloneyum industrial laser to burn through it.
BestBuy packaging - toughest stuff known to man.
Science advances one funeral at a time- Max Planck
And the desire of anyone with the ability or funds to do it to go to space regularly enough to need it. When I think back to being a kid and how space felt like the future, it makes me sad that typically it seems like no one besides researchers gives a shit anymore. I used to watch Star Trek and knew it wouldn't happen in my lifetime but it felt like that was the eventual goal and the direction we were heading in. Now I see it as the fantasy it is, because without some compelling financial gain in taking trips up there for anything besides tourism for the super-rich, I think we are going to stay stuck on this rock.
Or, just read the linked report by a team of ACTUAL scientists instead of a SCIENCE FICTION story written 35 years ago BY AN ACTUAL SCIENTIST.
FTFY.
Clarke had 256 pages and apparently conveyed the general ideas. Paying for 300 pages seems like a stupid thing to do if you want a general idea.
If they cannot communicate how it is feasible in an elevator speech, I don't expect to learn much in the manifesto.
3 pages has sufficed to explain the Higgs (excluding cartoons); I expect to understand the space elevator, in big boy words, in 2 or less. Anything else is hiding something, or so poorly written it cannot be trusted.
Superfluous vocabulary is ostensibly a plausible alternative, however a great many potential readers may find themselves sidetracked by such unnecessary verbosity. As such, I have expectations of a concise manner of thought conveyance as would be warranted by the writers. Vis a vis- said writer probabilistically desires their audience foremost not fall immediately into slumber.
My kingdom for mod points. This is sad but true. If we do ever leave it will be to mine unobtanium like in the movie Avatar, not to further mankind in general.
Picard tries to explain to Ralph Offenhouse from the 20th century that there would be no need for his law firm any longer: "A lot has changed in three hundred years. People are no longer obsessed with the accumulation of 'things'. We have eliminated hunger, want, the need for possessions." (TNG: "The Neutral Zone") - http://en.memory-alpha.org/wik...
Connected to a platform in space, the mass of the platform is to spin with the Earth's rotation. Centrifugal force is actually pulling on the elevator 'cable'.
$5 / month hosted VPS on linux = awesome!
Financial gain may be the most likely reason for advancement now, but it won't take more than another 50 to 100 years for it to become a necessity due to any combination of pollution, population, warfare, and resource depletion. Humans have always been really crappy at innovating unless we absolutely have to. When we aren't faced with some kind of crisis, we tend to get really good at perfecting known technologies and ideas, but that's about it.
So yeah, space exploration is pretty much out of the question as long as people (both investors and consumers) are more interested in mobile phone games and reality TV. As soon as shit hits the fan again -- and it will -- we'll see another big leap in advancement.
Have you read it? Let me know if it's any good. To me, it just looks like a scam to get people's money.
No money involved, they give it away for free if you know where to look:
http://www.virginiaedition.com/media/spaceelevators.pdf
Archived here:
http://www8.zippyshare.com/v/72888832/file.html
http://www.sendspace.com/file/16c8xj
http://wikisend.com/download/118300/spaceelevators.pdf
Yeah, if you want a materials strength nightmare, forget about the elevator cable.
Think about a foundation strong enough to withstand the pressures of a 100-200 mile high tower pressing down.
Why don't you think about familiarizing yourself with the concepts behind the space elevator? There won't be anything like that. The end of the cable "floats" in the receptacle. It hangs from its anchor asteroid.
Oh wait! Lemme get my unobtainium!
Why don't you instead get a quick education in the topic we're discussing before you flap your yap?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Someone found a free copy of the report. Enjoy.
"First they came for the slanderers and i said nothing."
Using the elevator for transfer of goods - will work but the goods will get a huge dose of radiation
Using it for transfer of organic matter (i.e. humans) above LEO is not feasible due to the speed/shielding needed
The worst part of Van Allen belt is about 19000km wide and starts at around 7000km high. Apollo moon missions passed trough it at roughly 15km/s, spending roughly 2*21 minutes in it.
The astronauts received roughly 1rem of radiation through 3 layers of thick aluminum radiation shielding.
That is 1/5 of the yearly the limit in US for people working with radiation.
At reasonable speed (~200m/s) the elevator would take ~26h to pass through the belt, meaning it would need at least 75x more radiation shielding than Apollo did and that the lift would need 15m thick aluminum honeycomb walls (using 70's technology).
Even with todays technology the shielding will be way too bulky/heavy for elevators to be viable alternative to rockets for above LEO human transfer.
I've seen proposals that talk about using a ribbon that is only just barely larger than is needed to support itself for the initial strand. Send it up in a conventional rocket (at the time this was discussed, they talked about using a Saturn V or possibly even the Space Shuttle; these days a Falcon 9 Heavy would probably be enough or even more-than) to geosync and have it unspool in both directions from there. Grab the lowered end as it reaches earth. Then, send up a small climber, carrying another, possibly even smaller strand of ribbon. Join it to the first one. Now you have a stronger ribbon. Repeat (potentially with increasingly large builder-climbers) until you have a strong enough ribbon for whatever you want to do (send up people, or ISS modules, or other satellites, or parts for a Project Orion-style nuclear pulse rocket to be constructed in space... you get the idea).
I don't know how feasible all the steps there are, but it's worth considering as an alternative to sending up the entire thing all at once.
There's no place I could be, since I've found Serenity...
I've always liked the idea of space elevators, but I've also been bothered by a problem that I've never seen addressed, "micrometeoroid erosion". Sure, you can build one. But how long is it going to last, with nothing to protect the main cable/strands/shaft/whatever-you-want-to-call-it from a near-endless --though admittedly low-rate-- series of impacts by speedy dust particles?
Protective polymer coating, topped up every time the car passes over it?
I believe the plastic in question is the kind of plastic that semi-permanently entombs your purchase in a chrysalis so touch that you need a diamond tipped super electro buzzsaw or a weapons grade baloneyum industrial laser to burn through it.
I bought one of those, but I can't open the package it's in.
Perhaps it hasn't been addressed much, but from what I've seen part of the 'protection' is that you would be more or less continously extruding new cable(on the order of a couple miles a day!), so as time goes by the cable WOULD be refreshed.
Besides that, if you're sensible you're going to orient your ribbon so it's the narrow end that's facing most probable impacts, highly limiting it's cross section. Then you have to factor in that this material will be the strongest material used in space to date; it should be quite resistant to those effects.
I don't read AC A human right
I'm not sure Star Trek should be considered in the same sentence as talk of viable space exploration the future.
Utopian thinking is nice but it's an ideal not a potential reality.
Main problem I foresee is what happens when someone presses all the buttons.
what it'll take it for China to start weaponising space, "for their own defence" and then funding will immediately be made available to get other countries weapons system up there.
Why else did the US go to the Moon - it was because there was a chance the Russians might have found a way to put missiles on there of course, all dressed up as exploration and "good of mankind".
So c'mon China - we're bored of terrorists, we need a new 'enemy' to spend vast sums defending against! you guys are the only ones with enough cash to do anything.
Speed of Light: 299,792,458 m/s (meters per second)
Great Pyramid Grand Gallery: 29.9792458N Latitude
coincidence?
Some drink at the fountain of knowledge. Others just gargle.
No more imperial powers? Seriously? You know where the European Space Agency launches their rockets from? French Guiana, which is a French territory in South America. Then of course there's the 800 lb gorilla. The US has actual territories around much of the world, from the Atlantic to the western Pacific, occupied or controlled countries around the rest, and military bases pretty much everywhere.
If a major nation wants to have an equatorial space elevator base they'll pick an appropriate country, throw some money at them, and get it.