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Space Elevator Update
TheMadReaper writes "The 2005 edition of the Space Exploration Conference in Albuquerque, NM came to a conclusion earlier this week. A large fraction of the conference was devoted to the Space Elevator. Surprisingly, there hasn't been much news coverage of this conference, perhaps because it doesn't have Space Elevator in its name. The most interesting fact I got from the conference is that money is really starting to exist in the space elevator world mainly thanks to the work of Dr. Bradley Edwards at ISR and at Carbon Designs, Inc. The strong nanotube talk was also more promising than last year."
What if you happen to get stuck at some weird altitude out of reach of help? If you're stuck high and above, you might have the space shuttle come and rescue you. If you're stuck low, you might have a helicopter come and help you. At other altitudes, you're pretty much fucked.
Jeez, try to imagine the havoc if the cable comes loose from its orbital anchor. Thousands of miles of pure splat! Whatever safeguards the builders promise, the NIMBY factor is so huge, it has no chance of happening.
Would somebody explain to me, what happens to this carbon nanotube when lightning strikes it and why it won't "cook" the thing?
A "space elevator" is totally unlike anything ever done before. As I read in a Slashdot post some years ago (referring to nanotubes, the favorite among space-elevator aficionados), "When somebody has built a 40,000 millimeter bridge across a creek on campus, then we can start to talk about a 40,000 kilometer bridge straight up".
The fact that we have not yet achieved one millionth of the task (and in fact fall several orders of magnitude for that) suggests to me that, much as I would love to see a space elevator in place, the job today belongs to materials scientists who are looking at shorter-term goals.
An eye to the future is great, but experimenting on climbers is like practicing the high jump: if you're jumping twice as high today as last year, I wouldn't start drawing any exponential curves. The ribbon is the really, really hard part, and we're currently so far away from it that research energy is better spent elsewhere for a while. 2010 is way, way too close.
Maybe with enough motivation we could get that 40,000 mm bridge by 2010, but somehow I doubt you're going to raise $10 million to build a bridge. The X-prize shot somebody into space for that kind of money.
I'm prepared to be wrong. I'm a software developer, and I've learned that as a consultant I can say, "Your project is doomed" with 95% accuracy before I've even heard your name. Being a nay-sayer is easy. But the real trick is being able to spot the 5% that will actually be profitable, and there are a lot of projects more immediately deserving of this kind of money.
My first thought upon hearing of the space elevator was "what happens if it breaks?" Who cares if science suggests it won't be a catastrophe? Most terrorists do not exactly subscribe to the latest scientific journals. A lightbulb will go off in one of their dim minds and they'll try to ram a plane into the cable, or the tower, or whatever, hoping it will somehow dislodge the asteroid from orbit and send it crashing into Washington D.C. or something. It'd make a great scifi action movie, wouldn't it?
And don't forget it'd be a tremendous icon of Western achievement. You'd better believe everyone in the US, or whatever country eventually builds one, would be proud as hell of it. The media would be going on and on about how it'll usher in a new age for mankind, and so on, and so forth. If terrorists could somehow take it out, wouldn't that have tremendous psychological value? Remember that they chose the World Trade Center and Pentagon to strike at us, two (or three) buildings that symbolized, to them, everything that's wrong with the US. Wouldn't a tower that reaches into the heavens (hello, Tower of Babel?) symbolize that even more?
It's quite reasonable to take terrorism into consideration when designing a structure. While I may be obsessing over the whole "living in fear" deal, its definitely something that needs to be considered.
Before this gets too far, somebody should call NORAD and ask them how many of the 2500+ satellites and other odd bits of junk traveling at 17551mph (LEO) cross the Equator (ascending and descending nodes) and might present a collision hazard. I could be wrong, but shouldn't the answer should be "Almost all of them."
This reminds me of the asteroid/comet problem, the probability of a significant impact might be low, but it only takes one.
The counter weight is in geostationary orbit, and would be weighted and positioned to balance the tension of the 300 miles of elevator against its orbital motion. The weight of the cargo is miniscule compared against the mass of hundreds of miles of carbon nanotube.
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Back in the 60s, the U.S. decided it had to go to the moon. If we'd done it right, we'd have done it in stages, building up an infrastructure of reusable vehicles and permanent orbital stations. But that would have taken too long. So instead somebody designed a huge rocket that cost $100 million a pop -- and could only be used once! Which is why nobody's been back to the moon for 30 years.
the reason behind that is just the same as "a chain is only as strong as it's weakest link"
as the rope get's longer it is more and more likely that a section of it is weak enough to break under the current load.
Snowden and Manning are heroes.
Yes, this is a big issue with space elevator designs. For this reason, you taper the cable, for instance. And supporting its own weight is the reason ridiculous strength/weight ratios are required (which are being approached by new nanosubstances). Designs call for widths around a centimeter or so, with multiple layers glued together, if I recall correctly. The material issue is probably the biggest theoretical problem still to be overcome, but the fact that we're so close so fast with nanotubes suggest that it's not long now. Many engineering and political problems, too, but those are at least theoretically solvable.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
Given all that, I'd imagine that a terrorist would turn their minds to any one of an infinite number of easier, but still spectacular, available targets. How well guarded are your local dams?
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
You don't seem to understand the current designs. The cable is small. In fact, the math works out that it can't be very big, because it needs to support itself. That recursive "supporting itself" is why it's been so problematic to get to the point where we can have materials that might be able to, but once we're there it works really well; there's a rather sharp dividing line.
Given that you don't understand current designs, I'd really rather you shut the fuck up about things you have no clue about. It's bad enough that nuclear energy has been FUD'ed nearly to death, do we really need half-cocked "technically educated" people running around, using their uneducated intuition in domains it is completely unsuited for, and scaring people with completely impossible scenarios?
Current designs have the space elevator designed as a ribbon of nano-tubules that are at most meters in width. A space elevator won't cast a shadow across a football field at that width, let alone "pretty much across the entire planet". Your intuition is guided by Science Fiction movies, where everything is always visible because it has to be to make good movies. But the space elevator is smaller than some satellites, and the shadows from satellites are hardly ruining our daytime, hmm?
Similarly for your extravagent claims about "altering weather". A small city will do more to alter the weather. An Elevator might have some localized electrical effects, but it's hardly going to change the climate. (Unless the elevator cars manage to exhaust things into the atmosphere and do something wacky, but even then, it'll just be another contrail-type of thing.)
Life is not a science fiction movie, where everything seems to take place in a universe where everything is just about the same size and in about ten or twenty cubic miles, total. The reality is, you won't be able to see the Space Elevator until you're nearly on top of it. It's small.
Intuition is not adequate for dealing with Space Elevators; it works almost nothing like you'd expect. (How many posters are still babbling on about crashing the Space Elevator by cutting it at the base, even though every time the topic comes up, it is completely correctly pointed out that an elevator cut at the base actually escapes into space? Earthly intuition does not cut it, and if such naysayers end up nixing a perfectly viable Space Elevator project in the future because of such ill-founded concerns, I will make it my life mission to seek them out and [violent threat deleted] for allowing such arrogant stupidity to prevent the best thing that could ever happen to Mankind from becoming a reality.)
Catastrophe. Yes Bad Things can happen. The amount of damage done is less than might be expected.
IS less? So this has been tested, has it?
I'll tell you what I'd expect. I'd expect if something went wrong and a "load" plummeted to earth from 5km up it would be pretty difficult to predict what sort of damage it would do... There's one of many possible catastrophes we'd like to hear whay you'd expect the damage to be
Terrorism. The thing is less a target than might be expected.
Again, IS less? This fact comes from where? A poll of known terrorists, or off the top of your head?
Yes, I know... people were executed for suggesting that the world wasn't flat, etc etc... but please - if you want a rational discussion on this thing pushing "facts" like these at us is hardly likely to sway any opinion.
No. Rather, what is desired is to construct a method of achieving orbit in a cheap fashion for the long term that has the lowest marginal cost and thus least resource use. The best way to reduce marginal cost and resource use is by making what is effectively a vertical train track and a system of cars, called in this case an elevator, that is cheap per unit of cargo due to cheap container costs for weight involved.
Holy Christ on a cracker are you a total fuckhead!!!
And people who know, like, a 1000 times more about it than you think it's possible some day.
So shut the fuck up, you backward loser, and let the men work on the future.
You might find it surprising, then, to hear that I'm very excited about the possibility of a space elevator, despite being a lifelong atheist.
It's true that the space elevator relies on technology that doesn't exist yet. But that technology is rapidly advancing, and there have been extensive studies of the material properties of carbon nanotubes in the context of use in a space elevator. Of course, you'll have to wade through pages of Biblical references to get to the actual science, but that's something you'll just have to get used to if you want to read about space elevator technology.
In addition, a mass driver is simply NOT a substitute for a space elevator. Even if a practical electromagnetic mass driver could be built, each launch would require a large amount of energy that would never be recovered. The space elevator uses less energy to send each ton of matter to GEO than any other proposed system, but that's not the really cool part. You see, each ton of matter that is returned from GEO effectively recovers the energy required to send that matter up in the first place via regenerative braking.
This is also where I should mention that, energy concerns aside, the space elevator removes one of the largest risks from space flight - reentry. Mass drivers help you get into orbit, but they don't help you return from orbit at all. In a space elevator, though, you just press the "down" button. Simple as that.
Now, if you'll excuse me, I have to go do my religion homework. Oops, I meant to say science homework. I have such a hard time keeping those two subjects separate... but you can't really blame us clueless space elevator kooks for that, right?
Alternately, you can observe that the mining industry has a much greater impact on the Earth's center of mass.
I am amazed at the lack of vision and basic technical knowledge most of the nay-sayers here on Slashdot display.
There is no doubt that it will take major developments in material sciences to make a SE practical. The possibility of breakage and sabotage would also have to be studied and mitigated. But right now, this is the only realistic possibility we have of becoming a space-faring species in the next couple of centuries.
An SE could lifts 10s of millions of tons of cargo into space each year. Once a critical mass of material and industry was in orbit it would be possible to colonize Mars and the Asteroid belt. Interstellar probes could be constructed and sent on their way. Trillions of dollar worth of palladium, silver, gold and platnium could be extracted from metallic asteroids to be used in manufacturing.
Is it risky, sure it is - but no more than crossing the Atlantic in a little wooden boat in the 15th century.
I agree that the people who think an elevator can be up and running within 15 years are probably overoptimistic to the point that you could call it "hype", but I've honestly never seen anyone besides you compare the space elevator to a biblical story.
Well, the emotional impact of going God on a cutting-edge science project aside, it's a particularly apt metaphor. I'm agnostic, but I see the value of the Bible as parables, other possible values remaining undiscussed. As is the case with all of the major holy books, the Bible provides a huge compendium of practical wisdom appropriate for everyday life, which helped its practicioners life better not only for themselves but also as a community. Considering human behavior before religion, this was a huge step, and should not be underestimated.
Most of those life lessons, the well decried exceptions like dietary law aside, still apply today, because most of them are about human nature and human emotional systems, which haven't changed much in the last five thousand years, or about ethics and morals, whose significant compass almost hasn't changed at all (note to argumentative philosophy majors: just because we understand morality better doesn't mean it's changed; just that we're less blind to it. The changes in moral compass come from ideas like the Ubermensche, and none of those have taken root in the common populace. Ever.)
The Tower of Babel parable is absolutely astoundingly appropriate, given its topical similarity to the question at hand. (That old rub about man's desire to build into the sky: just how dead-on is it? I've always wondered, especially when I lived near big skyscraper cities; people say it's about land value, but better mass transportation would be cheaper, more effective and safer, and there are a few cities which have implemented that at various levels throughout history - venice, graz, morgantown west virginia; tokyo's got it so bad that they've done it more than once, and they still need skyscrapers...)
Meh. Anyway, look. The point of the Babel fable is that the builders were experiencing hubris. They wanted to build a tower into the sky just for the sake of building a tower into the sky; they too should share the heavens. They didn't actually need, or in fact use, the tower for anything; they merely wanted to see the heavens, up close, whenever they wanted, and that was that. Indeed, in the modern day in many ways we do behave exactly this way: note for example the CN Tower, whose glass floor is most fun if one of your relatives can't handle it, and don't understand just how little impact you jumping up and down really hard actually has.
Now, these little bastards getting up into the heavens pisses god off, so god knocks them back down to the ground and gives them the anti-babelfish meme, and thus they can't talk to one another and therefore can't organize and build another one, which is roughly what plagues Los
Angeles, like um, to this day, okay fer shure. This is how The Bible works: it teaches life lessons by treating chance or happenstance as the Wrath of God, which is pretty much how Europe explained everything - for other parts of the world's excuses, qv Djinn, sprites, elves, demons, wu-jen, meckla, coyote trickster, aya'p'atl, hobgoblins, ashanti's children, and pretty much all those other things dungeons and dragons players are rattling off in their heads right now. The lesson here is only superficially "get your ass out of the sky, mammal;" certainly the original speaker wasn't being so literal, or else he'd also have some fairly atypical views about airplanes, possibly from the inside of a padded room.
The real lesson in the Tower of Babel story is that you shouldn't be doing dumbass things just for the sake of doing them, because sometimes they fail, and if you haven't even thought about what's going to happen when it fails, you're gonna get screwed, really really hard.
The Space Elevator is in fact such a case: think about the absolute nightmare a cab
StoneCypher is Full of BS