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Well it really does depend on the market, and how popular things get. I mean, we're extracting oil from tar sand in frigid northern Canada.

But the magic is in development for a space elevator to be built. Powering the climber is another challenge, but with something to hang onto, the cost of getting into space could drop by a factor of 10 to 100.

And for twice the length, you can get slinged into deep space. Mining the moon or mars have that gravity well to deal with, while the asteroids are just kinda floating around. Push them towards Earth and they'll get there eventually.

It's, you know, an "out there" idea. But if you want people to leave, they need a reason. If you want people to invest cash into the possibility, then they're going to have to have some sort of return.

maintaining geosynchronous orbit while tethered to the ground is not a good idea.

Sorry dude but that is the whole idea that makes it work.

there are so many factors that could turn a space elevator into a complete disaster. a cat-4 or 5 hurricane could potentially put so much drag onto the cable that the whole thing tumbles to earth.

Since you have it in GEO, it is tethered at the equator. Tropical cyclones(of which a hurricane/typhoon/cyclone is the extreme case) generally can't form within 5 degrees (300mi) of the equator. They require the coriolis force to initiate rotation and that's what gets the heat engine going. There are storms in the Intertropical Convergence Zone, but they are relatively small and a mobile sea platform should be able to avoid the worst of them. In addition, the equatorial zone's wet season is very short. In addition to that, there are very well known areas in the Pacific that see almost no storm activity at all.

an earthquake could yank it out of orbit.

Not if it's on a mobile sea platform. Even were it land-based, what's a couple feet of horizontal displacement on a 22,000 mile tether? As for tsunami, mid-ocean, they're only a couple cm tall and very long wavelength.

tidal pulls from the moon could rip it from the ground.

The tidal influence of the moon is very small 1/9,000,000 compared to earth's gravity. It doesn't pull the water away from the earth so much as drag it around in a heap like dirt swept before a broom. Other geostationary satellites don't get pulled out of orbit, why would the space counterweight?

lightning damage.

I don't have an answer for that one. Liftport does, however. Basically, they say, they'll stay out of the way just as with objects in orbit. In addition, they say that current materials could be used, but the mass required would make the thing financially infeasible.

i'd love to see this become a reality, but i just dont think that will happen.

I have more faith in materials science.

What the fuck is web 2.0 anyway? Everyone seems to have their own definition. There are eerie similarities between this web 2.0 nonsense and the Liftport space elevator vaporware : http://www.liftport.com/

What research do you base this statement on?

The NASA feasibility study from the mid-90's.

This is completely ridiculous. If that's true, why don't we already use wireless power?

Because doing a whole house like that would take a lot of power, cause a lot of RF interference, and probably react badly with pacemakers. In any case, we're not looking at powering a bunch of light bulbs over an area, but rather beaming power to a specific target. A later study (PDF link) discusses using a laser for this purpose. Microwaves are also possible.

Our response to the Pugno paper is here - in turn linking to an older Forum post - is here - http://www.liftport.com/progress/wp/?p=839

I can just imagine the PHB at Dilbert's cube announcing that he's come up with plans for a space elevator.

From their Wiki page:

Our goal is a significant return on investment - whether or not - the Space Elevator is ultimately successful. We do this by concentrating on 2 things: generating profits through spin-off technologies, and learning what we need to learn, in order to achieve our long-term goals.

The Four Pillars dictate how the rest of the world interacts with us; while the Five-C's are examples of how we interact with the world. Collectively these are referred to as The Nine and are used when considering the action matrix for building our elevator to space."

Four Pillars? Five Cs? The Nine?

Who are these kids, and how did they get access to enough money in the first place that now some government entity finds them worth investigating?

Looking through page after page of their gallery section, I ask myself what photograph after photograph of empty rooms and open spaces across a very large piece of real estate says about how they're handling money. Take a look through yourself. (Try not to stumble over the poor grammar and poorly written comments.)

Honestly ... if you had a fledgling company focusing on an extremely fledging idea, would you put your money into renting or buying buildings like that? Or would you perhaps start of with something smaller, like Bill Hewlett and Dave Packard?

But whatever ... I just wish *I* had an action matrix!

I can just imagine the PHB at Dilbert's cube announcing that he's come up with plans for a space elevator.

From their Wiki page:

Our goal is a significant return on investment - whether or not - the Space Elevator is ultimately successful. We do this by concentrating on 2 things: generating profits through spin-off technologies, and learning what we need to learn, in order to achieve our long-term goals.

The Four Pillars dictate how the rest of the world interacts with us; while the Five-C's are examples of how we interact with the world. Collectively these are referred to as The Nine and are used when considering the action matrix for building our elevator to space."

Four Pillars? Five Cs? The Nine?

Who are these kids, and how did they get access to enough money in the first place that now some government entity finds them worth investigating?

Looking through page after page of their gallery section, I ask myself what photograph after photograph of empty rooms and open spaces across a very large piece of real estate says about how they're handling money. Take a look through yourself. (Try not to stumble over the poor grammar and poorly written comments.)

Honestly ... if you had a fledgling company focusing on an extremely fledging idea, would you put your money into renting or buying buildings like that? Or would you perhaps start of with something smaller, like Bill Hewlett and Dave Packard?

But whatever ... I just wish *I* had an action matrix!

http://www.liftport.com/papers/SE_Roadmap_v1beta.p df page 3 in the credits. Your source is helping the competition...

I posted a 'cousin comment' to this about Liftport. Their plan is that each upbound launch grows the current cable a little bit. When the cable grows wide enough they split it into two elevators. However, because it is still much cheaper to let gravity bring something down, they plan to use the 2nd elevator to simply double their uplift capability (as well as provide redundancy in case one of the elevators fail).

I recently attended a presentation by the guys at Liftport. I am just repeating what they said. Different companies may have different plans.

Stuff goes up the elevator slowly compared to a rocket. To get any sort of use out of a cable, multiple payloads must be sent up at the same time. I do not know the exact figures, but you can imagine a payload travelling up the cable on every few miles of the cable. Bringing something down means you cannot put anything up. It is much easier and cheaper to drop something from space and have it land intact than it is to put something into space. It makes much more economic sense to only use the expensive elevator to put stuff into space and use cheap gravity to bring stuff down.

Most of the energy of a rocket is used to lift the fuel for the rocket. An elevator is much cheaper since you only have to lift the cargo and vehicle. The ability to reclaim this energy does not offset the lost opportunity cost of the multiple payloads that could be lifted while something decends the cable.

I'm kind of surprised that the forward-thinking, technically-oriented, mensa-qualified slashdot crowd would be so negative about this (not universally, I realize.) I would have thought you would have taken a "we can solve this, go for it" approach instead of screaming it can't be done. For a positive approach, see: http://www.liftport.com/ Buy the book. Read the stories. Check out what's been done so far. It's just a matter of time. Naysayers will be left on earth.

I have been following this for some time... Here are a few links for ya.
http://www.isr.us/Downloads/niac_pdf/contents.html Study
LiftPort Group. Company wants to beat NASA.
Reference Site



Place a curse on the RIAA/MPAA

Phantom (nee Infinium) meet LiftPort

Indeed, you are quite right that nanotubes have countless possible applications. These might (will) include highly efficient power transmission lines, more resilient and greatly strengthened materials, molecule-thin conductive sheets, neural interfaces, breaking moore's law by many magnitudes in processor development, and so on, but these possibilities are hardly exclusive. Such applications will immensely valuable in the future, and the various industries represented by that list are very much attuned to new developments. For example, a power transmission publication featured CNTs as its cover story just recently. ..As soon as big industry takes notice and demand increases, so will the quantity and quality of nanotube manufacture, and price will drop like a stone.

The tech is barely past a decade since its inception, so as you might imagine it is still in its infancy. Yet, there are actually quite a few groups working on manufacturing and marketing CNTs right at this very moment. In fact, the organization behind most of the recent space elevator press is Liftport. While looking to the skies, they are no starry-eyed optomists, and they recognize the great deal of work required to get to the level of materials technology capable of supporting the elevator.

As such, they are doing the R&D and capitalizing on the results. See this page for the beginning of what will soon be a booming industry.

This has already been addressed by Liftport, the company actually doing the work here:

I've discussed the article with a couple of CNT researchers, and they say that they're not convinced by the paper. My attitude is that we have to wait and see what really happens, because there's a lot about carbon nanotubes that we don't know yet.

Despite anyone's predictions, we won't know what the material will be like until it's made. There's a LOT of other work that needs to be done on SE development regardless of what the material winds up being. And in the "worst" case, you can still build a space elevator on the moon with near-term materials.

One thing to remember is that, even if bulk CNT were limited to 30 GPa, we could still build the space elevator. It would just become limited by finances. That's because, with a density of 1300kg/m^3 and a strength of 30GPa, the mass of a seed ribbon (using the same assumptions as in my November article - safety factor of 2, and 1,000kg capacity) would be roughly 3,440 tonnes (i.e., 3.44*10^6 kg), or roughly 170 rocket launches (using current medium-lift rockets) to loft it (i.e., ~80 times as massive as in the 2002 NIAC report). The expense and logistics of creating a seed ribbon at that point (assuming you're launching from Earth) becomes much more daunting, but not impossible.

and for people raising other concerns, which I see in several places here:

Breaking is a minor issue. Most of it would fall up. The base station doesn't support the elevator, it holds it down. The Earth's rotation keeps it up. People tend to forget the scale we're dealing with here. The bits that fall down would burn up, land as ash.

Space debris is well mapped. We can avoid it, for the most part. Small adjustments made from either end of the elevator can be used to shift the bulk of the thing. Remember, serious plans for it call for building it on a floating platform, which can move, and rockets can be used to adjust the space end of things.

Storms, well, like I said, we can move the thing. Also bear in mind that storms only affect the part of it in the lower atmosphere. Resonance is an issue which is being seriously considered, as well as induced current.

Any more problems you'd like to raise? Read the wikipedia article.

Not necessarily so. http://www.liftport.com/

I believe that a space elevator is going to be the best method to get lots of mass into orbit, or out to a space station, quickly and cheaply.

A few groups are already testing and/or holding competitions to expedite innovations:

Lift Port:
http://www.liftport.com/index.php?site=news&news_i d=3

Elevator2010.org:
http://www.elevator2010.org/site/index.html

You only get *realistic* taper factors at over 100GPa.

Incidentally, here is a paper from the research director at LiftPort regarding minimum tensile strength. Taper for a 50 GPa cable is ~10. A 50 GPa cable is very heavy - ~450 tonnes - but it's absolutely not unreasonable. Especially for a government.

50 GPa is still much stronger than current materials, absolutely. But it's far more reasonable than 100 GPa.

If they were doing work with the carbon nanotubes, I'd be much more impressed.

From the LiftPort web site:

Our 15,000 sq. ft. Nanotube facility is gearing up to produce large quantities of mid-grade multi-walled carbon nanotubes for commercial and research use. We're entertaining partners interested in co-development, or leasing space in our facility to further development of CNT composites with glass, plastics, and certain metals.

Located in Millville, NJ, LiftPort Nanotechnology is ideally located for composite research. The region has a long history of composite and glass development with an excellent skilled labor pool. The local city and county governments are very motivated to help develop new technologies and have capital investment programs available.

I love LiftPort forums.

This pretty much summarizes a lot of what I said, more cleanly.

People are not recognizing the difficulty in building a climber like this. It's just insulting.

The challenges of a space elevator aren't in the climber; they're in the cable.

C'mon. That's not true. The main reason it seems like this is because you think you know how to build the climber, but you have no idea how to build the cable. Ask a materials scientist who's working on carbon nanotubes, and they might disagree with you.

Plus, you do not need a 100 GPa cable. You need a 100 GPa cable for a small taper. At 50 GPa the taper becomes ... well, large, but not unreasonably large. It would just cost a lot more.

There are a lot of issues with the climber design. A lot. Speed, reliability, weight, and power. Reliability in particular will take a lot of time to nail down. It makes sense to tackle that one first, because it can be done in parallel with the cable design, and in addition, the third major challenge (power delivery) can't really be done until the climber design is finalized.

So you've got three difficult tasks - the cable, the climber, and the power delivery system. The last two are coupled. What makes sense is having two separate tasks, one of which handles the cable, the other the climber, and then the power delivery system. Oh look! That's exactly what they're doing.

Given our lack of experience in building cheap vehicles that can travel 100,000 km with zero failures (with low power, in vacuum) I think it's safe to say that all parts of the elevator are difficult.

The company (liftport) has some pictures and videos on their site.

Here's some concept art

Ok, the simple response to that is, "then why is there already so much junk in orbit?" but that seems to be addressed more in a previous thread, so let's think about the space ladder, or space elevator (which has had to slow its progress due to worries of what would happen if space debris collided with the tether).

From this LiftPort's website (http://liftport.com/research2.php) "According to several NASA studies, a space elevator would dramatically reduce the cost of sending payloads into space. The same studies estimate that the cost of sending payloads into space could be reduced from $20,000 per pound down to $400 per pound." Yes, this is a commercial site explaining the benefits of its proposed product, but I've also read about the cost difference in Wired and heard it other places.
You make a good point in that expensive things are rarely wasted, but all that changes when those things stop being expensive, and something tells me that "true colonization of space" will probably happen once the cost comes down, not before it does.

I disagree - we see an increase in attention (one metric is people signing up to our maillist at http://www.liftport.com/lists.php) every time 'space elevators' are in an entry. Granted none of these folks are customers and we're not generating revenue so YMMV.

Sorry 'bout that. It's: http://www.liftport.com/faq.php

I'm sure I don't know, but the folks at LiftPort Group have a FAQ which they provide their answers to many, if not all, of the points you make.

Granted, they are in the business of selling the Space Elevator concept, but they can do math too.

To paraphrase Richard Nixon, I am not a Dickhead! though I have read most of his novels.

But the "discussion" is about space elevators/sky hooks. And the one remaining technological hurdle is coming up with a material that will support the elevator and will not snap, and the only thing available, as far as I can tell, is carbon-nanotube-based fiber. That is why LiftPort (http://www.liftport.com/) is building their plant at Millville for the specific purpose of providing the technical and financial support for a space elevator they plan to build by 2018. As for the tenor of my post, it was in response to a single instance of a multitude of responses whose basis in fact is what the posters perceive to be true and not what is readily accessible on the web. And my complaint is that there has been a flurry of such offtopic threads of late that focus on some tiny little bit of a factoid that has nothing to do with the actual story, the main reason for which seems to have something to do with the attitude that the posters are smarter than the expert because they know more about xyz than he does. I would, actually, rather read a discussion of the details of the story, if that isn't asking too much.

Since there is many basic questions and confusion what stage is space elevator program in I recommend checking out this (warning, pdf): http://www.liftport.com/files/521Edwards.pdf

Yes, it was a serious interview. The idea of a space elevator has been bandied around in scientific and science fields for a number of years, but the strength of the cable needed to hold it up was always a sticking factor. With the discovery of Carbon-60 (Buckyballs and Buckytubes) the strength factor is theoretically within reach.
The basic idea is an elevator with its center of gravity at geosyncronous orbit, making the elevator stay in one spot over the earth. It would allow for much larger space lift capacities and much lower costs per pound.
Read more at:
Wikipedia
The Space Elevator Reference
Liftport Group, a consortium of companies working on space elevator tech
Also, for a good sci-fi treatment of space elevators, read Kim Stanley-Robinson's Red-Gree-Blue Mars Trilogy

Without doing the math

That explains a lot. Now, I admit my numbers might be slightly, or even quite far off. Still, even if I'm off by several orders of magnitude, I believe I can put your mind at ease somewhat.

A quick search on Wikipedia provides some numbers for the asteroid impact believed to be responsible for wiping out the dinosaurs (link). Let us say it was approx. 10 km in diameter, and roughly spherical. Let us further assume it was composed of porous rock with a density of around 1500 kg/m^3. That gives us an estimate of around 900,000,000,000,000kg for its mass, or around 9*10^11 metric tons.

Now, let us assume that for the past century, we had launched 1000 tons per day into orbit. In truth, we are many orders of magnitude below that. Assume it all remained in orbit, so did not fall back to Earth or go elsewhere in the solar system. That would mean there would now be around 3.7*10^7 metric tons in orbit, or less than 0.005% of the mass of the above asteroid.

Simply put, we do not have the ability to launch something that could cause that much damage into orbit. Not even close. A more likely scenario is that a few fragments of extremely light carbon ribbon would splash down into the ocean with about as much force as a falling leaf, with most of the ribbon burning up on re-entry into the atmosphere. Or, to put it another way:

it's perfectly safe. Nothing to worry about.

For more information, I would suggest reading the entry on that LiftPort has published in their FAQ. If that is too biased for you, there are plenty of other sources that come to the same conclusion.

I have been following the progress of research concerning space-elevator for some time now. The LiftPort Group of companies working towards a space-elevator are making a great deal of progress. See here and here for more LiftPort specific information. Slashdot reported on the faa approval of their high altitude tests several days ago -- refer to that thread for some interesting discussion. Check here and here here for several reports concerning the viability of the elevator -- be sure to check the NIAC pdf. Also, Blaise Gassend has a great collection of information. Finally, though carbon nanotubes are still in their infancy (its been a little over 12 years since they were discovered) - their theoretical tensile strengths are perfect for use in the construction of a space elevator tether. This recent development spells a rosy future, and many innovations yet to come.

I have been following the progress of research concerning space-elevator for some time now. The LiftPort Group of companies working towards a space-elevator are making a great deal of progress. See here and here for more LiftPort specific information. Slashdot reported on the faa approval of their high altitude tests several days ago -- refer to that thread for some interesting discussion. Check here and here here for several reports concerning the viability of the elevator -- be sure to check the NIAC pdf. Also, Blaise Gassend has a great collection of information. Finally, though carbon nanotubes are still in their infancy (its been a little over 12 years since they were discovered) - their theoretical tensile strengths are perfect for use in the construction of a space elevator tether. This recent development spells a rosy future, and many innovations yet to come.

It's kinda annoying to see every space elevator article attract a swag of ill-informed comments that get modded as insightful. Please go read question 4 of the FAQ.

the ribbon recovers for the same reason that it stays up in the first place. Centripetal acceleration is acting on the counterweight pulling it outward, and the lost angular momentum is replaced very quickly (essentially as fast as it is lost). The ribbon will never lose enough angular momentum to even deflect a single degree, let alone fall. The extra angular momentum is stolen from the Earth's rotation; we will have to worry about this effect slowing down the Earth and making the day longer if we ever decide to ship Australia into space.

First off, CN is cyanide; please use proper terms
Sheesh, what are you, the Acronym Police? I'll use whatever I please. It's not that hard to tell when I mean cyanide vs Carbon Nanotubes, unless you're an idiot.

Current designs call for half what you claim they need.

http://science.nasa.gov/headlines/y2000/ast07sep_1 .htm

"The desired strength for the space elevator is about 62 GPa. Carbon nanotubes... appear to have a theoretical strength far above the desired range for space elevator structures."

Second, that is a false statement. Even individual tubes aren't that strong.

http://www.liftport.com/faq.php

What are some frequent Space Elevator misconceptions?

"Nothing is strong enough to make a Space Elevator."

Carbon nanotubes (CNT), discovered in 1991, are almost certainly strong enough. Theory says that they are 3-5 times as strong as we need them to be, and laboratory measurements of their strength, though very difficult to do and not yet definitive, have shown more than half the strength we need.

The longest nanotubes thus far are measured in centimeters, not kilometers, and certainly not 100,000 km.

We don't need and are not counting on individual carbon nanotube molecules running the entire length of the space elevator or any significant fraction thereof. The individual fibers in a string or rope are only a few millimeters long, yet the rope has a large fraction of the theoretical strength of the fibers. This is even more the case with MOLECULES, several orders of magnitude smaller than a fiber. A diamond is said to be the "hardest substance in the world" because of the strength of the carbon bonds that make it up, but a diamond is not a single molecule. Likewise an SE could be made with CNTs just a few centimeters or millimeters long. (In fact, a CNT several centimeters long is a wonder; they're single molecules!)

Please see:

http://www.isr.us/Downloads/niac_pdf/contents.html

Phase I NIAC Paper

http://www.liftport.com/faq.php

Frequently Asked Questions regarding the SE endeavour, from LiftPort Group

Sorry for the repost, some of the stuff got cut off before due to my Slashdot noobness. Feel free to mod my other post out of existence.

I still see a lot of comments from naysayers that are based on outdated technology and SE specs. A lot has happened in the last year or two, guys. White papers dealing with everything from cable design (a ribbon seems to be the answer) to weather to electrical charge have been published.

There are still technical problems, some of which we probably don't even know about yet. But there is a design for a cable of 40 - 60% CN that should be strong enough. CN mass production facilities are being built. NASA is taking the concept seriously enough that their guys are writing white papers.

It ain't pixie dust anymore.

Detailed info and links below. http://science.nasa.gov/headlines/y2000/ast07sep_1 .htm

"The desired strength for the space elevator is about 62 GPa. Carbon nanotubes... appear to have a theoretical strength far above the desired range for space elevator structures."

http://www.space.com/businesstechnology/technology /space_elevator_020327-2.html

"The hurdle to date, Edwards said, has been the commercial fabrication of carbon nanotubes. Both U.S. and Japanese firms, among others, are ramping up production of carbon nanotubes, with tons of this now exotic matter soon to be available. "That quantity of material is going to be around well before five years time. It's not going to take long," he said."

http://www.liftport.com/faq.php

Frequently Asked Questions regarding the SE endeavour, from LiftPort Group

(a LOT of very good info here, here's a couple regarding points I've seen here)

What are some frequent Space Elevator misconceptions?

"Nothing is strong enough to make a Space Elevator."

Carbon nanotubes (CNT), discovered in 1991, are almost certainly strong enough. Theory says that they are 3-5 times as strong as we need them to be, and laboratory measurements of their strength, though very difficult to do and not yet definitive, have shown more than half the strength we need.

The longest nanotubes thus far are measured in centimeters, not kilometers, and certainly not 100,000 km.

We don't need and are not counting on individual carbon nanotube molecules running the entire length of the space elevator or any significant fraction thereof. The individual fibers in a string or rope are only a few millimeters long, yet the rope has a large fraction of the theoretical strength of the fibers. This is even more the case with MOLECULES, several orders of magnitude smaller than a fiber. A diamond is said to be the "hardest substance in the world" because of the strength of the carbon bonds that make it up, but a diamond is not a single molecule. Likewise an SE could be made with CNTs just a few centimeters or millimeters long. (In fact, a CNT several centimeters long is a wonder; they're single molecules!)

"The elevator would be susceptible to a terrorist attack. "

First of all, it's important to point out that there will be more than one Space Elevator. We plan to build a second one immediately (using the first to make it much cheaper) and expect that the second will immediately be used to build a third, fourth, etc. An attack on any one ribbon is unlikely because of the anchor stations' isolation and the relatively small number of casualties that would result. Terrorists are unlikely to be able to break the elevator anywhere higher than 15 km or so; it can then be simply flown back down to the anchor by moving some of the counterweight mass a bit further out and will be back in operation in a couple of days.

The first anchor will be located in the equatoria

I see a lot of comments from naysayers that are based on outdated technology and SE specs. A lot has happened in the last year or two, guys. White papers dealing with everything from cable design (a ribbon seems to be the answer) to weather to electrical charge have been published.

There are still technical problems, some of which we probably don't even know about yet. But there is a design for a cable of 40 - 60% CN that should be strong enough. CN mass production facilities are being built. NASA is taking the concept seriously enough that their guys are writing white papers.

It ain't pixie dust anymore.

http://science.nasa.gov/headlines/y2000/ast07sep_1 .htm

"The desired strength for the space elevator is about 62 GPa. Carbon nanotubes... appear to have a theoretical strength far above the desired range for space elevator structures."

http://www.space.com/businesstechnology/technology /space_elevator_020327-2.html

"The hurdle to date, Edwards said, has been the commercial fabrication of carbon nanotubes. Both U.S. and Japanese firms, among others, are ramping up production of carbon nanotubes, with tons of this now exotic matter soon to be available. "That quantity of material is going to be around well before five years time. It's not going to take long," he said."

http://www.liftport.com/faq.php

Frequently Asked Questions regarding the SE endeavour, from LiftPort Group

(a LOT of very good info here, here's a couple regarding points I've seen here)

What are some frequent Space Elevator misconceptions?

"Nothing is strong enough to make a Space Elevator."

Carbon nanotubes (CNT), discovered in 1991, are almost certainly strong enough. Theory says that they are 3-5 times as strong as we need them to be, and laboratory measurements of their strength, though very difficult to do and not yet definitive, have shown more than half the strength we need.

The longest nanotubes thus far are measured in centimeters, not kilometers, and certainly not 100,000 km.

We don't need and are not counting on individual carbon nanotube molecules running the entire length of the space elevator or any significant fraction thereof. The individual fibers in a string or rope are only a few millimeters long, yet the rope has a large fraction of the theoretical strength of the fibers. This is even more the case with MOLECULES, several orders of magnitude smaller than a fiber. A diamond is said to be the "hardest substance in the world" because of the strength of the carbon bonds that make it up, but a diamond is not a single molecule. Likewise an SE could be made with CNTs just a few centimeters or millimeters long. (In fact, a CNT several centimeters long is a wonder; they're single molecules!)

"The elevator would be susceptible to a terrorist attack. "

First of all, it's important to point out that there will be more than one Space Elevator. We plan to build a second one immediately (using the first to make it much cheaper) and expect that the second will immediately be used to build a third, fourth, etc. An attack on any one ribbon is unlikely because of the anchor stations' isolation and the relatively small number of casualties that would result. Terrorists are unlikely to be able to break the elevator anywhere higher than 15 km or so; it can then be simply flown back down to the anchor by moving some of the counterweight mass a bit further out and will be back in operation in a couple of days.

The first anchor will be located in the equatorial Pacific 650 kilometers from any air or shipping lanes. The ribbon would also have restricted airspace around it. The ribbon and anchor would be protected like any other valuable piece

they are looking at building a space elevator in a more northern/southern position which has nice cool water on a island.
Um, actually they aren't. The plan is to have the base on a ship at sea, near the equator, a couple hundred miles from the nearest land.

http://www.liftport.com/about.php

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.

Liftport addresses this quite nicely in their FAQ:

http://liftport.com/faq2.php#science2

# What if the ribbon breaks?

* How easy would it be to break?
Very difficult. The planned position of the elevator avoids hurricanes, lightning and other extreme weather. The ribbon is engineered to be twice as strong as it needs to be to support itself and any planned cargo attached to it.

* What if it falls?
The majority, the long end out in space, gains enough speed that it burns up in the atmosphere, with the lower portion falling into the sea. It will not fall on top of anyone.

* For the portion that doesn't burn up in a fall - what effect will it have on the environment?
Honestly, it will make a little bit of a mess. But New York City tickertape parades have made bigger messes. Comparatively it will put much less dust, dirt, debris and chemicals into the environment than wildfires of the American west, any one of the large expendable rockets, or a month of natural meteors hitting Earth. The ribbon is light (7.5 kg/km) so, any pieces that fall to earth will slow down, in the air, to about the same terminal velocity as that of an open newspaper page falling. It will not have enough momentum to cause mechanical damage when it comes down. We have considered other health risks such as inhalation of very small fragments and believe this will not be a problem but we are conducting studies to make sure this isn't a problem. Since we are aware of the possible problems now we can design the elevator to avoid these issues.

* How large a wave/disturbance would it generate?
The wave/disturbance would be nonexistent. As above, there just isn't enough mass, even in later, larger, ribbons, to generate such energy dispersion. There might be a small amount of light as a line in the sky as the ribbon burns up but after that it will be a few pieces of black film fluttering to Earth. Because of the size, distribution and winds, it is conceivable that only a few people would even see the event in any way and just as few would find actual pieces of the ribbon.

* How much warning would there be from the time of a break to the time it would take for the lower portion to come down?
Depending on exactly what happened it could be a few hours to weeks.

* What would happen to the surviving portion?
The ribbon that fell to Earth could be recovered for study but because of the amount and distribution it would be difficult to find many pieces. The pieces that do land would eventually degrade but not for a very long time. Keep in mind that this is mostly a stable form of carbon; it doesn't do anything. The debris would resemble long hair and would probably be broken up in interactions with animals, plants, wind, fish and waves. In fiber form it would be much too large to inhale and would probably work its way through a digestive system unaffected. The only debris we have any concern about is if it were reduced to nanotube size. This we don't understand yet so we will study this to see if there is a problem and then probably also design the ribbon to remain in larger pieces if it re-enters.

* What would happen to anything climbing the ribbon at the time it broke?
The short answer is that some payloads will fall (below the break and below 24,000 km altitude), some will enter low orbit (below the break and between 24,000 km and GEO) and some will be tossed to high Earth orbit (above GEO) depending on where the payloads are and where

That's right. Never give up. Instead, you should form a group of people with enough buzzwords and bs to attract investors, like this organization (http://www.liftport.com/about.php) has done.

Hit the PR machine really hard; if you get published in blogs and the NYTimes and speculative stories in PopSci and IEEE Spectrum, then you will attract even more investors.

Then profit, and get out of the business when enough knowledgeable people discredit your 'vaporware' technology.

You know you want to. Before you post that brilliant point about why it can't be done, go read the faq and see how the respond to the million other people who made the exact same point. Maybe you'll buy it, maybe not, but I'm tired of reading "but what about hurricanes?" every time we have a space elevator discussion.

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 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.

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.

Goto: http://www.liftport.com/donate.php

...and they are asking for donations, saying:

"Developing the space elevator will require large amounts of financial capital over the next 10-15 years. At the present, LiftPort Inc. is in the early start-up stages, and like any start-up, has strong financial needs in order to achieve our goal of building the space elevator. If you would like to help support our efforts by making a donation, please click the link below. We thank you for your support."

It makes me feel so good to know i've helped a newborn business down the path of global domination!

Hooray for groveling private enterprise!

+5 Cynical

Does anyone else think that perhaps this article should be linked to the actual source instead of a link to a link that links to another site with a quote from the original source and no link to it? I mean at what point does this become a rumor when it's so far from the original source? Oh here's the link to the companies website: http://www.liftport.com/ And here's one to their staff blog which is much more interesting reading then this quote: http://www.liftport.com/progress/wp/ And heres a link to their september newsletter posted on their forums that talks about the FAA approval among other things: http://www.liftport.com/forums/showthread.php?t=25 3

Does anyone else think that perhaps this article should be linked to the actual source instead of a link to a link that links to another site with a quote from the original source and no link to it? I mean at what point does this become a rumor when it's so far from the original source? Oh here's the link to the companies website: http://www.liftport.com/ And here's one to their staff blog which is much more interesting reading then this quote: http://www.liftport.com/progress/wp/ And heres a link to their september newsletter posted on their forums that talks about the FAA approval among other things: http://www.liftport.com/forums/showthread.php?t=25 3

Does anyone else think that perhaps this article should be linked to the actual source instead of a link to a link that links to another site with a quote from the original source and no link to it? I mean at what point does this become a rumor when it's so far from the original source? Oh here's the link to the companies website: http://www.liftport.com/ And here's one to their staff blog which is much more interesting reading then this quote: http://www.liftport.com/progress/wp/ And heres a link to their september newsletter posted on their forums that talks about the FAA approval among other things: http://www.liftport.com/forums/showthread.php?t=25 3