Space Elevator Conference Wraps Up 93
slavitos writes "The
Space Elevator: 2nd International Conference,
organized by the
Los Alamos National Lab
and the
Institute for
Scientific Research
has just finished its work in New Mexico.
To be sure, most people still think
it's absolutely ridiculous to even consider building
such a thing.
However, that's exactly what organizers
wanted - an open discussion on the issue, plus
some free PR."
hmmm... (Score:1, Insightful)
imagine the propagana and demoralising effects a hit on such a target could produce.
Ok, so the shuttle seems less practicle, but this isn't the answer.
I think it's a pipe dream - a nice, exciting pipe dream, but still a pipe dream
Re:hmmm... (Score:4, Insightful)
Well, it's a ribbon in a very remote location, without large numbers of civilians nearby.
If you believe it's a terrorist target, then Cape Canaveral must be a bigger target - easier to reach, easier to hit. Is that a good reason to stop sending rockets into space?
Re:hmmm... (Score:1)
We have a very brave group of people who are willing to risk their lives going up in it, but that doesn't make it safe. Even the good track record the space program has still had setbacks - see Challenger. See Apollo 1. See the recent space shuttle explosion.
This is a thin (think slice of paper here), hard to see, easily defendable position in the deep Pacif
Re:hmmm... (Score:3, Insightful)
Only if you make it big. Currently plans involve a high tensile line and an elevator rather than the multi-tonne segmented 'bomb on a string' ideas that have entertained through science fiction, and it should be okay as long as you stop the Port Authority from writing their own rules.
"imagine the propagana and demoralising effects a hit on such a target could produce"
As opposed to, say, a
Re:hmmm... (Score:5, Insightful)
On the other hand, cities are extremely robust. Certainly high tech assualts such as bioterrorism could be a great concern, but proven terrorist methods are low tech -- typically delivering a large quantity of explosive in front of a highly populated building. The World Trade Center attack was undoubtedly the most spectacular terrorist "success", but as catastrophic as they were for the structures, if you look at them as an attack on the city, they were remarkably ineffective.As disruptive as they were, NYC basically continued to function even through 9/11, and today it runs more or less the same as it did on 9/10/2001.
The Space Elevator would be a tempting target for terrorists, since it could be attacked using low tech weapons, if they could be delivered. We shouldn't underestimate their creativity in doing this.
Re:hmmm... (Score:3, Insightful)
An attack on a remote freight elevator that happens to extend out to geosynchronous orbit would not engender the same psychological effect.
Re:hmmm... (Score:3, Interesting)
This reminds me of consulting with clients anout Internet security. The common attitude is "nobody would want to hack me". I always tell them that every reason they can think of for them not to be a target, somebody out there will interpret the other way.
Really, if I were a terrorist, I'd be opportunistic. If I had the opportunity to destory a project like this,
Re:hmmm... (Score:2)
From that standpoint, it makes sense to believe that a terrorist organization will attack a $2B carbon ribbon at the equator.
But will it cause massive loss of life? Will it change lives? Will it engender fear in the hearts of the infidels? No. That's why I believe that ultimately, in the current global political climate, a space elevator is in a position of mitigated risk from terrorist attack.
Re:hmmm... (Score:1, Insightful)
If you break it at a high altitude, it's gonna fall, but with current designs it will harmlessly disintegrate.
Either way, it will probably require a military action, rather than a terrorist one, since the elevator will be in the ocean, hundreds of miles from anywhere, and well-guarded by an aircraft carrier group or two if the U.S. has the slightest interest in protecting vital infrastructure.
Re:hmmm... (Score:4, Insightful)
Why? Why would they want to strike it? Would it cause a big commotion? No. Would virtually anyone even know it happened? No.
And here's the big reason why terrorists would NEVER bother going after the space elevator:
Would it even bring it down? No.
Terrorists would likely strike the elevator far below GEO - remember the elevator is almost 100,000 km long, and they'd be striking it within the bottom few km. This would do nothing. The operators would be like "Oh, jeez, those stupid terrorists tried to do something again, the elevator's drifting. OK, spool out another km of cable." The ONLY place that striking it would do ANYTHING is if you struck it near GEO, and if terrorists develop the technology to do an orbital strike at GEO, I've got a feeling they'll target other things besides the space elevator.
The second main reason that attacking the Elevator would be useless is that even if they broke the first cable, this wouldn't even be that impressive. The marginal cost for deploying a second cable is trivial (the Conference notes said $2B, but I think they'd win out far more than that due to economies of scale - plus they doubled several things like power distribution which wouldn't be necessary for a 'backup cable'. The ribbon itself was estimated at $400M).
You could imagine it on the news. "Elevator cable #21 was damaged beyond repair today by an explosive package concealed within a launch satellite. Consortium members have already stated that a replacement cable has been moved into position and unspooling has already begun. Full operation is expected to resume in a few weeks."
I mean, seriously. Saying the Space Elevator is a tempting target for terrorists is like saying the International Space Station is a tempting target for terrorists. Sure, it might be. But it's not like it would EVER happen.
Re:hmmm... (Score:1)
Terrorists would likely strike the elevator far below GEO - remember the elevator is almost 100,000 km long, and they'd be striking it within the bottom few km. This would do nothing. The operators would be like "Oh, jeez, those stupid terrorists tried to do something again, the elevator's drifting. OK, spool out another km of cable."
Remember however that the line is under very high tension, many thousands of tons equivalent. If it breaks and drifts it's not so easy to catch, hold on to, and reel bac
Re:hmmm... (Score:2)
Remember however that the line is under very high tension, many thousands of tons equivalent. If it breaks and drifts it's not so easy to catch, hold on to, and reel back in.
You reel down from orbit, not from the ground. You don't need to grab it. It'd bounce, and oscillate a bit when it broke.
Not really, though - the tension is not coming because it's attached to anything - it's coming from the cable's existence. Cables normally spring upwards and bounce because the tension on them goes from "huge" to
Re:hmmm... (Score:3, Insightful)
True, destroying the Space Elevator would be a big demoralizer, and thus a big draw for the terrorists. Destroying elevator #6 of 27 wouldn't be such a big deal, though. That's why one of the first projects given to Space Elevator #1 should be the lifting up into orbit of Space Elevator #2, and so on.
Re:hmmm... (Score:1, Insightful)
Ok so why don't we then stop any work that is of worldwide importance or significance:
Yeah I am sure if we stop all the major projects the terrorism will cease to be!
W
You're right (Score:2, Insightful)
Re:hmmm... (Score:1)
And somehow this country that seems to be so proud of it greatness is going to let a little group of underarmed, undertrained and underfunded morons to influence what they build and what they research?
Re:hmmm... (Score:2, Interesting)
Flip it around. It's a means to get cargo to space (and maybe the only one) that can't readily be used as a weapon.
The base is fixed geographically. The cargo going up is dead slow, visible, and easy to track.
This is a good thing in wartime. Combatants can agree it's not a threat, and leave it alone.
Re:hmmm... (Score:1)
by Robert Heinlein. What comes up just might come back down, and we could "throw rocks"
really well from geosynchronous orbit.
Re:hmmm... (Score:1)
Won't this thing make an astonishingly large target for terrorists, or even for enimies in a wartime situation?
Enemies (not enimies) of who, exactly? I assume you mean enemies of the United States. Did I miss something? Is this an American space elevator? As for the terrorists, I think all the Bush rhetoric CNN et al spout is getting to you.
imagine the propagana and demoralising effects a hit on such a target could produce.
I can't imagine what propaganda (not propagana) any terrorist/enemy could use
Nearly impossible to destroy from groundRe:hmmm... (Score:3, Informative)
To take it out in a big way you would have to load a bomb onto a elevator car and take it up to quite high altitude, taking maybe a few days or a week, before detonating it. Needless to say, with sensible security practices at the embarkation point this is unlikely to be a problem.
Re:hmmm... (Score:1)
a hurricane will wipe it out... (Score:1)
considering the nature of this think by the way, wouldn't it make sense for the bottome to rest on the equator at the very place where the earth can give it the most centrifigal force? if so , i cant think of any particular hurricane free zone in that area...
Re:a hurricane will wipe it out... (Score:3, Interesting)
You put enough weight on the cable to equal the tension that's holding the low end down, then detach the end. Then the weight climbs up above the storm, rol
Re:a hurricane will wipe it out... (Score:1)
neat ideas you have...
Re:hmmm... (Score:1)
But we could throw things at them from very high up.
Re:hmmm... (Score:2)
Dude, you should have so been modded up for that comment.
The thing that worries me at the moment is that the space race is gearing up again, and despite treaties to the effect that are supposed to destroy the idea of space territoriality, I can see a big problem coming up.
Orbital flechettes are a fairly low tech method of wiping out countries. None of that real technical jiggery-pokery, just a big rock, an accurate orbital vector and a decent rock
Re:hmmm... (Score:2)
Terrorist schmerrorist (Score:1)
Benefits? (Score:2, Interesting)
Seriously, to many people, a "space elevator" is going to sound like the "escalator to nowhere" from the Simpsons - a fairly frivolous-sounding projet, and not as inspiring as rockets. Okay, so it'll make space exploration cheaper - what be
Re:Benefits? (Score:4, Interesting)
It's the same way with the current space program. We're always putting world hunger second :P
Anyhow, the benefits are obvious. If taking stuff to space doesn't require the shuttle (an outdated extremely costly concept that is extremely error prone), not to mention cheaper, then eventually ordinary people will get into space as well.
But the same question applies. What's the current space program have to do for ordinary people? Can you answer that? Good, now imagine all those satellites were far cheaper. Yeah, global communication does kick ass doesn't it?
Cheaper space exploration will benefit us as science takes advantage. It's just a matter of time.
Re:Benefits? (Score:2)
Second? Gawd, I hope it's not *that* high on our list. I can think of a lot of things I want done first with *my* money. The rest of the world can take care of its own food needs.
Re:Benefits? (Score:2, Funny)
"Mr Mackenzie?"
<weak from lack of food> "yes..?"
"Mr Andrew Mackenzie?"
"yes..."
<I present a laminated printout of the above post>
"Ha. Ha, ha. Ha ha ha ha ha. Would you like some cake? Well you can't have any. Ha ha ha ha ha ha ha ha ha."
I'm looking forward to it.
Re:Benefits? (Score:1)
Re:Benefits? (Score:2, Insightful)
you know that thing about us giving more foriegn aid than anyone else... it's not true. But that anger... the anger... it comes from somewhere, I'm just not convinced it comes from a knowledge of world affairs.
Japan (Score:2, Informative)
However, per capita or as percent of GNP, the US is very low on the list. It depends how you count.
We give a lot away, but a lot of that comes back as those countries contract with american engineering firms, or buy american arms, and I just don't like the indignation of the parent post, where the assumption is that we are great, we save the world, we are selfless, and they just hate us anyway... biting the hand
World Hunger (Score:1)
Try space industrialization (Score:2)
The infrastructure can also be used to build powersats relatively cheaply. Would the Third World benefit from being able to buy power cheaper than they can get it in the form of oil from the Arabs? Would we? The other obvious point is that the sun isn't running out of juice anytime soon, which is something we can't say about oil.
That's just the beginning
Re:Benefits? (Score:2, Insightful)
Many of the benefits of space do not come from advances in rocket engines or anything like that, they come from spinoffs of the space program.
Tools designed to examine telescope photos for any variety of things have been converted for use in medical uses: the MRI is a simple example of this.
Hand tools were first developed for the Apollo space missions.
Pretty much anything involving miniaturization has
Re: Hand Tools (Score:2)
My grandfather made things out of wood, and he sometimes held pieces of wood together using little tapered cylinders of iron or steel called "nails" and "screws".
It was very difficult to cause these cylinders to enter the wood simply by pressing on them, so he used hand tools called "hammers" and "screw drivers".
All of this occured long before Apollo.
Re:Benefits? (Score:5, Insightful)
Well, once you have cheap access to space, a whole bunch of things suddenly become much more profitable.
Example: most near-Earth asteroids contain very high quantities of heavy metals. There are all sorts of things you can do with iridium, platinum or gold alloys. How would you like a car that ran off ordinary petrol but used a fuel cell instead of an IC engine? Quieter, lighter, cheaper, more reliable --- provided you can get the palladium catalysts required to make it work.
Example: it would be possible to start mass producing things in microgravity. Defect-free crystal growth would lead to much cheaper electronics among other things. If you can get the cost of access cheap enough, even mundane things like steel refining will change: vacuum foam steel girders would be cheaper, lighter and stronger than conventional rolled girders.
Example: Outside geostationary orbit is a great place to be if you want to do something hazardous. Want to build a really messy experimental nuclear power reactor? Now you can do it and it won't be in anyone's back yard.
Example: there's more you can do with a space elevator than get to orbit. They provide an ideal anchoring point for telecommunications systems, among other things: put a communications complex 500km up and you've got LEO-quality satellite communications while still able to use fixed position dishes. Plus it's repairable. Cheaper satellite TV, anyone?
Example: low gee hospitals .
Example: Tourism!
These are just a few examples I can think of off the top of my head --- I'm sure that given a few minutes thought I could come up with some more. The great thing about a space elevator is not that it's directly profitable, but that it's an enabler. It makes a whole bunch of other things become profitable, and opens up the possibility for a whole variety of other industries, currently unthought of, that would be even more profitable. It provides new wealth to the economy, which produces long-term gains in the same way that feeding starving children (although an admirable goal in itself) or building aircraft carriers just don't do. It's the old teach-a-starving-man-to-fish argument: invest, don't spend.
Re:Benefits? - Troll (Score:1)
Re:Benefits? - Troll (Score:2)
Tim
Re: Starving People (Score:4, Interesting)
Comment removed (Score:5, Insightful)
Re:Benefits? (Score:2)
Re:Benefits? (Score:2)
Re:Benefits? (Score:1)
You're already spending ten times as much on the shuttles, and those things are orders of magnitude less useful than a space elevator.
Well, actually I think there are quite enough aircraft carriers on Earth. Anyways, a space elevator's military potential is orders of magnitude greater than an aircraft carrier, especially if the lasers us
Re:Benefits? (Score:1)
Re:Benefits? (Score:5, Insightful)
Re:Benefits? (Score:3, Interesting)
That instant gratification problem is indicative of short-term thinking...one of the reasons why we're heading for a cataclysm. You should know that they've been pouring funding into hot fusion for decades, and the benefits have been less than tangible. The same with quite a few advanced propulsion methods.
It never comes down to the thing you actually want, though. In surmounting the technical hurdles you come across stuff that is actually quite cool
Re:Benefits? (Score:5, Insightful)
How much of your money do you give to starving people as food instead of buying a nice car, nice house, nice clothes?
As you are free to use your own property as you see fit, so are people with more property, and that includes talking about building a space elevator.
Sam
Re:Benefits? (Score:2)
Re:Benefits? (Score:2)
Want more war like Iraq? (Score:5, Insightful)
I'll bet you didn't like the war in Iraq (going on a limb here, you might have). Would you approve of the US/UN going to war and knocking out several other "innocent" goverments? (for some definition of innocent?) Most starvation is caused by goverments not allowing the food, of which there is more than enough, to get to the people who need it. Generally they have a political gain of some sort to doing so. (you might not see it as a gain, but they do)
As for a space elevator. Well I think private eneterprize should do it, which means get NASA out of the way and loosten up the laws preventing private companies from going to space. (Okay, it isn't exactly illegal, but it is nearly impossible to get the permits) At least in the US this is a problem.
Re:Want more war like Iraq? (Score:1, Troll)
Actually, starvation is caused by modern medicine. The child, who died in an illness 50 years ago, is cured by modern medicine now. However, the environment can't support the increased population in most third world countries. It sounds crude but we should not give medicine to the third world countries and nat
Re:Benefits? (Score:2)
Re:Benefits? (Score:3, Insightful)
Remember, we can't solve everything. That's why we need to explore despite the other things we have to take care of.
Re:Benefits? (Score:1)
There are huge amounts of heavy metals in space that could be mined using a Space elevator. There is good chance that large amount of aluminum, iron, uranium and other such useful metals will exist in huge quantities (many billion of tonnes) on close to earth asteroids.
Assuming the technology required to mine such materials existed after the construction of such an elevator.. it would quickly pay for itself..
Simon.Re:Benefits? (Score:2, Interesting)
We could lift things (or people) into orbit without spending huge amounts of money on
risky attempts at rocketry, making space exploration a much more easily obtainable goal.
Imagine a fifth grade science project that's taken into orbit for $1000.00. Not $40,000.00 per
pound, but much, much cheaper. Micro-satellites could be sent up in bunches, and deployed with
decaying orbits. Truely disposable, because they are so cheap
It would be very useful (Score:5, Insightful)
Re:It would be very useful (Score:4, Insightful)
Yah, of course, you'd still have chemical rockets for course correction - it'd be silly otherwise. But those rockets would be so small that they wouldn't even be considered rockets, and the only REAL reason for them is contingency.
It may even be far more interesting than that. The whole reason you need to aerobrake at entry points is because of a velocity difference between a transfer orbit and a normal Earth orbit - that is, you're moving faster than a normal Earth orbit. However, so is the elevator. With very clever timing, you might not even need to aerobrake at all, which makes it even easier. You just time your approach so that you and the elevator are at the same point, and that you're at the height on the elevator such that your velocity is the same as the elevator's, and you just grab hold. No stress, no problems.
Re:It would be very useful (Score:2)
With very clever timing, you might not even need to aerobrake at all, which makes it even easier. You just time your approach so that you and the elevator are at the same point, and that you're at the height on the elevator such that your velocity is the same as the elevator's, and you just grab hold. No stress, no problems.
Yeah right, no stress, unfortunately, if you don't catch the tether you go off into space and
Re:It would be very useful (Score:2)
Well, the "if you don't do it right, you die" comment is true for ANY space operation. If you don't calculate the release time correctly, you miss Mars completely. Zip! Off you go!
This is why computers need to handle this sort of thing, and not rely on engineers entering in data in the correct units. It's a simple calculational problem, but the penalty for making a mistake is huge.
With enough time, and enough debuggi
Re:It would be very useful (Score:2)
Um, yeah granted, but the aerobraking window at Mars is particularly narrow- the 'atmosphere' of Mars is very tenuous. Let's put it this way: Buzz Aldrin doesn't like it at all.
Financing shouldn't be hard, though again, a government agency would likely be the one to do it.
Mommy state will help you out? Maybe, if there's votes in it.
But the point is that there's very little relative velocity between you and the elevat
Re:It would be very useful (Score:3, Interesting)
Hence the reason that a computer should be the one to do it. Computers don't have to like it. They just have to do it.
Mommy state will help you out? Maybe, if there's votes in it.
Nah, this is simple economics. If
End of the world (Score:1)
Conference notes / reports on LiftWatch (Score:2, Informative)
It sounds like the conference was a success. Critics were given some podium time, and Arthur C. Clarke updated his now famous prediction to a bolder "10 years after everybody stops laughing". (He originally said "50 years after everyone stops laughing".)
At LiftWatch [tiki-web.com] we're putting up reports by people who attended, as they become available. Blaise Gassend, one of the speakers, posted some good notes on the first two days of the conference.
Conference Preaches Double Standard (Score:5, Funny)
Despite the cost saving benifits of the elevator approach to accessing space, they are still advocating the ongoing use of shuttles as can be seen at the bottom of their about page [www.isr.us].
Re:..build it at the north pole! (Score:2, Insightful)
No tower. A ribbon extends to, and past GEO, for one. Read the report - google for NIAC final report or highlift
Re:..build it at the north pole! (Score:1)
The Earth's radius is around 6500 km, IIRC, that's around 4000 miles I guess. Since a=omega^2 * R (centrifugal force), and g=k*m*M/R^2 (gravity).... I'm too laze, you do it. Anyways, I don't expect the gravity at 100 miles be less than .9 g. The difference in gravity on the equator versus at the pole less than 2%, IIRC, and the difference in radius on the poles/equator is about 25 km (16 miles).
Re:..build it at the north pole! (Score:1)
Re:..build it at the north pole! (Score:1)
That's why the plans always are for a tower along the equator, so that the top of the tower could be placed in Geostationary orbit, i.e. it orbits the earth at the same rate it rotates. So the top of the tower has enough momentum to keep it in space with or without the tower. So lower down an extremely resiliant cable (carbon nano-tubes) h
Maybe not accessible? (Score:2)
The WTC was accessible in part because it was in the middle of a city. If this thing was built in the middle of Nellis Air Force Base (for example), just getting within sight of it would be a challenge.
Re:Maybe not accessible? (Score:2, Informative)
Re:Maybe not accessible? (Score:1)
And in that sort of positioning, you can also give the tower and lower reaches some serious firepower to keep unauthorised boats and planes away from it.
It just makes sense. (Score:5, Insightful)
The way I look at it is this. We have been shooting humans into space atop monolithic, ubelievably dangerous explosive devices. A rocket is an explosive device.
If space were a cliff and we wanted to get on top, the current way we are doing it is by laying a board over a fulcrum, sitting a guy on one end and dropping a volkswagen on the other. Boing! he flys through the air and rolls to a stop atop the cliff. How does he get down? he jumps and hopes to land on a soft spot. Lots, LOTS can go wrong, and death is almosts as likely as success.
The space elevator is the equivalent of (rather than launching someone up) throwing a rope and hook up the cliff face, securing it, and then weaving a rope ladder.
Higher success, cheaper (no volkswagen involved), and safer (though less exciting and dramatice albeit).
Re:It just makes sense. (Score:2)
J.