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I've seen this stuff... somewhere, and it looks just like black string.

There are some pictures of real carbon nanotubes in plexiglass containers available here, taken with my crappy digital camera at LiftPort.

Cool story: at one point some of this material, which looks more or less like soot, spilled onto the flat, seemingly smooth table top. After wiping it off, there was a permanent black smudge left on the table top that no amount of scrubbing would remove... some of the nano-scale CNTs had slipped down into the microscopic grooves and divots on the table surface!

A few days ago here on Slashdot there was a link to an interview that The Onion AV Club was running with Arthur C. Clarke. I found it intruiging that (1) Clarke says that Fountains of Paradise is still his personal favourite of his published works, and (2) that he's hoping for it to be made into a film shortly.

Here's Fountains on Amazon (no affiliation) if you want to check out the reviews.

While there is a difference between achieving 100 GPa over very short lengths and over 100,000 kilometers, it's not as much as you might think.

The longest individual nanotubes we can reliably produce are on the order of a couple of centimeters. But once we have nanotubes on the order of a meter long, they will probably be sufficient to produce a long ribbon with sufficient loading on the nanotubes themselves.

The limiting factor is not the length of the nanotubes in a composite (beyond a certain point, anyway), but rather how effectively the nanotubes themselves can be made to bear the load. Nanotube exteriors are slippery, like graphite, so the challenge is being able to stick them together in a substrate the transfers load effectively between them.

For this, a process known as "functionalization" comes into play. This basically means adding small appendages to the nanotubes so that they have more traction within the substrate.

LiftWatch.org carries regular space-elavator news items. Here are some recent articles on CNT advances:

• Rice produces pure, macro-scale nanotube fibers
• Kettering Researchers Discover New Way to Produce Nanotubes
• New CNT production technique for strength and conductivity
• UC Davis team develops durable CNT composite
• Zyvex gets research grant from NASA

While there is a difference between achieving 100 GPa over very short lengths and over 100,000 kilometers, it's not as much as you might think.

The longest individual nanotubes we can reliably produce are on the order of a couple of centimeters. But once we have nanotubes on the order of a meter long, they will probably be sufficient to produce a long ribbon with sufficient loading on the nanotubes themselves.

The limiting factor is not the length of the nanotubes in a composite (beyond a certain point, anyway), but rather how effectively the nanotubes themselves can be made to bear the load. Nanotube exteriors are slippery, like graphite, so the challenge is being able to stick them together in a substrate the transfers load effectively between them.

For this, a process known as "functionalization" comes into play. This basically means adding small appendages to the nanotubes so that they have more traction within the substrate.

LiftWatch.org carries regular space-elavator news items. Here are some recent articles on CNT advances:

• Rice produces pure, macro-scale nanotube fibers
• Kettering Researchers Discover New Way to Produce Nanotubes
• New CNT production technique for strength and conductivity
• UC Davis team develops durable CNT composite
• Zyvex gets research grant from NASA

While there is a difference between achieving 100 GPa over very short lengths and over 100,000 kilometers, it's not as much as you might think.

The longest individual nanotubes we can reliably produce are on the order of a couple of centimeters. But once we have nanotubes on the order of a meter long, they will probably be sufficient to produce a long ribbon with sufficient loading on the nanotubes themselves.

The limiting factor is not the length of the nanotubes in a composite (beyond a certain point, anyway), but rather how effectively the nanotubes themselves can be made to bear the load. Nanotube exteriors are slippery, like graphite, so the challenge is being able to stick them together in a substrate the transfers load effectively between them.

For this, a process known as "functionalization" comes into play. This basically means adding small appendages to the nanotubes so that they have more traction within the substrate.

LiftWatch.org carries regular space-elavator news items. Here are some recent articles on CNT advances:

• Rice produces pure, macro-scale nanotube fibers
• Kettering Researchers Discover New Way to Produce Nanotubes
• New CNT production technique for strength and conductivity
• UC Davis team develops durable CNT composite
• Zyvex gets research grant from NASA

While there is a difference between achieving 100 GPa over very short lengths and over 100,000 kilometers, it's not as much as you might think.

The longest individual nanotubes we can reliably produce are on the order of a couple of centimeters. But once we have nanotubes on the order of a meter long, they will probably be sufficient to produce a long ribbon with sufficient loading on the nanotubes themselves.

The limiting factor is not the length of the nanotubes in a composite (beyond a certain point, anyway), but rather how effectively the nanotubes themselves can be made to bear the load. Nanotube exteriors are slippery, like graphite, so the challenge is being able to stick them together in a substrate the transfers load effectively between them.

For this, a process known as "functionalization" comes into play. This basically means adding small appendages to the nanotubes so that they have more traction within the substrate.

LiftWatch.org carries regular space-elavator news items. Here are some recent articles on CNT advances:

• Rice produces pure, macro-scale nanotube fibers
• Kettering Researchers Discover New Way to Produce Nanotubes
• New CNT production technique for strength and conductivity
• UC Davis team develops durable CNT composite
• Zyvex gets research grant from NASA

While there is a difference between achieving 100 GPa over very short lengths and over 100,000 kilometers, it's not as much as you might think.

The longest individual nanotubes we can reliably produce are on the order of a couple of centimeters. But once we have nanotubes on the order of a meter long, they will probably be sufficient to produce a long ribbon with sufficient loading on the nanotubes themselves.

The limiting factor is not the length of the nanotubes in a composite (beyond a certain point, anyway), but rather how effectively the nanotubes themselves can be made to bear the load. Nanotube exteriors are slippery, like graphite, so the challenge is being able to stick them together in a substrate the transfers load effectively between them.

For this, a process known as "functionalization" comes into play. This basically means adding small appendages to the nanotubes so that they have more traction within the substrate.

LiftWatch.org carries regular space-elavator news items. Here are some recent articles on CNT advances:

• Rice produces pure, macro-scale nanotube fibers
• Kettering Researchers Discover New Way to Produce Nanotubes
• New CNT production technique for strength and conductivity
• UC Davis team develops durable CNT composite
• Zyvex gets research grant from NASA

While there is a difference between achieving 100 GPa over very short lengths and over 100,000 kilometers, it's not as much as you might think.

The longest individual nanotubes we can reliably produce are on the order of a couple of centimeters. But once we have nanotubes on the order of a meter long, they will probably be sufficient to produce a long ribbon with sufficient loading on the nanotubes themselves.

The limiting factor is not the length of the nanotubes in a composite (beyond a certain point, anyway), but rather how effectively the nanotubes themselves can be made to bear the load. Nanotube exteriors are slippery, like graphite, so the challenge is being able to stick them together in a substrate the transfers load effectively between them.

For this, a process known as "functionalization" comes into play. This basically means adding small appendages to the nanotubes so that they have more traction within the substrate.

LiftWatch.org carries regular space-elavator news items. Here are some recent articles on CNT advances:

• Rice produces pure, macro-scale nanotube fibers
• Kettering Researchers Discover New Way to Produce Nanotubes
• New CNT production technique for strength and conductivity
• UC Davis team develops durable CNT composite
• Zyvex gets research grant from NASA

I was particularly interested in the last couple of paragraphs, regarding a possible film adaptation of Fountains of Paradise, and the fact that Clarke considers that his best/favourite novel.

Fountains was the first novel to incorporate the modern concept of a space elevator.

Anyone heard anything else about this news item?

Personally, I'm hoping for Steven Spielberg. He did a terrific job on Minority Report. Between that, AI, and Taken, he's definitely on a sci-fi roll lately.

A space elevator is totally infeasible at the moment. It is absolutely safe to predict that none of us will see such an installation realized in her or his lifetime.

Um, moderators... please take a moment to reconsider why you thought the parent comment deserved a +5, Informative. To me, it just reads like a troll.

Such predictions are never absolutely safe. In the case of a space elevator, you must be aware of recent feasibility studies commissioned by NASA. Although some advances in CNT (carbon nanotube) composite strength are still needed, there is every possibility that these will occur in the next couple of decades, if not sooner.

See What is a Space Elevator? for more...

A space elevator is totally infeasible at the moment. It is absolutely safe to predict that none of us will see such an installation realized in her or his lifetime.

Um, moderators... please take a moment to reconsider why you thought the parent comment deserved a +5, Informative. To me, it just reads like a troll.

Such predictions are never absolutely safe. In the case of a space elevator, you must be aware of recent feasibility studies commissioned by NASA. Although some advances in CNT (carbon nanotube) composite strength are still needed, there is every possibility that these will occur in the next couple of decades, if not sooner.

See What is a Space Elevator? for more...

Space Elevator R&D fits perfectly with the national space strategy. An enduring, heavy-lift system, with low amortized cost would of course be ideal. But regardless of whether one actually gets built or whether the concept even works, research dollars in that direction would be very well spent because of the great potential for spin-off products and materials.

This is a perfect opportunity to put a bug in their ear about the space elevator concept, as one /. poster has already done.

See this related story on LiftWatch.org.

I haven't seen any good ideas for something that will cheaply [make it above LEO].

That UPI article is actually a 3-parter. Here are all three parts at spaceref.com:

• Part 1
• Part 2
• Part 3 (the one linked in the story)

Also, here's the LiftWatch.org story.

I don't see that kind of strength-to-weight ratio being produced any time in the near future.

Pure carbon nanotubes have the required strength-to-weight ratio. The only question is how long before we can develop a composite that binds CNTs together into a material that retains enough of the strength of pure CNTs. Steady progress is being made. Keep an eye on LiftWatch.org for regular updates on this and related techs.

...this neglects the fact that you need to go to geosync orbit rather than LEO, and also that you need to grab an asteroid for the counterweight, and that you need to do on-orbit fabrication of a material barely out of the laboratory right now...

You need to read about more recent deployment plans for the space elevator. Start here.

Things you got wrong:

• There are viable deployment plans wherein we only need to launch 100-200 tons to GEO... and these can be divided between several payloads.
• No in-orbit fabrication of anything is required. The ribbon is manufactured on Earth.
• An asteroid is not required for a couterweight. The initial counterweight will be on the order of perhaps 100 tons, which is feasible to launch, as you point out.

--
LiftWatch.org - Space Elevator News

...this neglects the fact that you need to go to geosync orbit rather than LEO, and also that you need to grab an asteroid for the counterweight, and that you need to do on-orbit fabrication of a material barely out of the laboratory right now...

You need to read about more recent deployment plans for the space elevator. Start here.

Things you got wrong:

• There are viable deployment plans wherein we only need to launch 100-200 tons to GEO... and these can be divided between several payloads.
• No in-orbit fabrication of anything is required. The ribbon is manufactured on Earth.
• An asteroid is not required for a couterweight. The initial counterweight will be on the order of perhaps 100 tons, which is feasible to launch, as you point out.

--
LiftWatch.org - Space Elevator News

Unless they plan on catching everything they launch again, then we will slowly be slowing the earth down.

True, but very misleading. We will be slowing the Earth down by a NEGLIGIBLE amount.

You know, when you drive a heavy truck East, you are actually slowing the Earth's rotation by a small amount due to the same law of conservation of (angular) momentum.

The Earth is VERY heavy, however. 6.6x10^21 tons. So you would have to move many billions of tons of mass in order to have a measurable effect on the Earth's rotation.

Not to worry.

--
LiftWatch.org - Space Elevator News

I think you need to have a look at Liftwatch. There are a lot of announcements such as these. There are nanotube advancements almost every month, and a whole bunch of universities and corporations worldwide are throwing rather large sums at putting it under heavy research. A 1km cable with 2% CN loading was already constructed a while ago. Smaller stretches were already made with 5% loading at the time the NIAC phase II was written, and was mentioned in said paper.

You neither need to grow a 35000km buckytube, nor do you need to reach a 100% CN-loaded ribbon.
Composites will be made with a higher and higher CN loading, and once a certain percentage is reached (feel free to check the NIAC 2 paper which draws this line quite clearly), you'll have elevator-worthy material. At the rate CN loading in composites has been increasing in the past decade or so, we should [hopefully] have elevator-worthy material in about 2 years.

Cheers.

I think you need to have a look at Liftwatch. There are a lot of announcements such as these. There are nanotube advancements almost every month, and a whole bunch of universities and corporations worldwide are throwing rather large sums at putting it under heavy research. A 1km cable with 2% CN loading was already constructed a while ago. Smaller stretches were already made with 5% loading at the time the NIAC phase II was written, and was mentioned in said paper.

You neither need to grow a 35000km buckytube, nor do you need to reach a 100% CN-loaded ribbon.
Composites will be made with a higher and higher CN loading, and once a certain percentage is reached (feel free to check the NIAC 2 paper which draws this line quite clearly), you'll have elevator-worthy material. At the rate CN loading in composites has been increasing in the past decade or so, we should [hopefully] have elevator-worthy material in about 2 years.

Cheers.

I think you need to have a look at Liftwatch. There are a lot of announcements such as these. There are nanotube advancements almost every month, and a whole bunch of universities and corporations worldwide are throwing rather large sums at putting it under heavy research. A 1km cable with 2% CN loading was already constructed a while ago. Smaller stretches were already made with 5% loading at the time the NIAC phase II was written, and was mentioned in said paper.

You neither need to grow a 35000km buckytube, nor do you need to reach a 100% CN-loaded ribbon.
Composites will be made with a higher and higher CN loading, and once a certain percentage is reached (feel free to check the NIAC 2 paper which draws this line quite clearly), you'll have elevator-worthy material. At the rate CN loading in composites has been increasing in the past decade or so, we should [hopefully] have elevator-worthy material in about 2 years.

Cheers.

I think you need to have a look at Liftwatch. There are a lot of announcements such as these. There are nanotube advancements almost every month, and a whole bunch of universities and corporations worldwide are throwing rather large sums at putting it under heavy research. A 1km cable with 2% CN loading was already constructed a while ago. Smaller stretches were already made with 5% loading at the time the NIAC phase II was written, and was mentioned in said paper.

You neither need to grow a 35000km buckytube, nor do you need to reach a 100% CN-loaded ribbon.
Composites will be made with a higher and higher CN loading, and once a certain percentage is reached (feel free to check the NIAC 2 paper which draws this line quite clearly), you'll have elevator-worthy material. At the rate CN loading in composites has been increasing in the past decade or so, we should [hopefully] have elevator-worthy material in about 2 years.

Cheers.

LiftWatch.org - regular news updates, links directory, etc. All about space elevators and related techs.

Also, building the space elevator involves moving insane amounts of mass around.... There's no reasonable way to build a space elevator without nuclear propulsion.

We're not talking thousands of tons to launch a space elevator.

We're talking 100-200 tons. And it could be divided into several payloads.

I'm not trying to argue against the idea of nuclear powered rockets here... but they would not be REQUIRED in order to raise a space elevator because the amounts of mass we're talking about are really not 'insane'.

--
LiftWatch.org - Space Elevator News

A shockwave that destroys significant amounts of life on Earth isn't impossible.

Sorry to disappont the Kim Stanley Robinson fans, but this simply isn't the case.

Even if the SE breaks at halfway, we're not going to get a catastrophic shockwave. You have to consider the material to know how it's going to behave. First, this thing is VERY light weight. It's also VERY thin. Not much displacement means not much shockwave. Not much weight means it will be easily dampened by the atmostphere.

After a break, yes, the end near the break will start off at a pretty high velocity because of the tension that it was under. But -- and this is part of the design -- carbon is combustible and will BURN UP in the atmosphere if it's travelling too fast.

There is NO WAY that a falling CNT ribbon will be catastrophic, even to those right underneath it.

You'd be better advised to worry about payloads that might fall off it. But even these would be engineered to have re-entry systems for just such an eventuality.

--
LiftWatch.org - Space Elevator News

I'm glad to see so many space elevator stories on Slashdot lately. I think the actual feasibility of this idea is important to impress upon people. SE research has a considerable amount of NASA funding, the fruits of which where the Phase I & II NIAC reports mentioned in the parent post.

LiftWatch.org is a news/portal site dedicated to following this and other developments in space elevators and related technologies. Besides the main front page news, here are some handy links for the SE afficianado:

• What is a "Space Elevator"?
• Links directory
• Concept artwork

I've been trying to get Slashdot to add LiftWatch headlines as an RSS feed. If you find the site interesting, please let the /. editors know so that there can be a LiftWatch.org slashbox.

I'm glad to see so many space elevator stories on Slashdot lately. I think the actual feasibility of this idea is important to impress upon people. SE research has a considerable amount of NASA funding, the fruits of which where the Phase I & II NIAC reports mentioned in the parent post.

LiftWatch.org is a news/portal site dedicated to following this and other developments in space elevators and related technologies. Besides the main front page news, here are some handy links for the SE afficianado:

• What is a "Space Elevator"?
• Links directory
• Concept artwork

I've been trying to get Slashdot to add LiftWatch headlines as an RSS feed. If you find the site interesting, please let the /. editors know so that there can be a LiftWatch.org slashbox.

I'm glad to see so many space elevator stories on Slashdot lately. I think the actual feasibility of this idea is important to impress upon people. SE research has a considerable amount of NASA funding, the fruits of which where the Phase I & II NIAC reports mentioned in the parent post.

LiftWatch.org is a news/portal site dedicated to following this and other developments in space elevators and related technologies. Besides the main front page news, here are some handy links for the SE afficianado:

• What is a "Space Elevator"?
• Links directory
• Concept artwork

I've been trying to get Slashdot to add LiftWatch headlines as an RSS feed. If you find the site interesting, please let the /. editors know so that there can be a LiftWatch.org slashbox.

I'm glad to see so many space elevator stories on Slashdot lately. I think the actual feasibility of this idea is important to impress upon people. SE research has a considerable amount of NASA funding, the fruits of which where the Phase I & II NIAC reports mentioned in the parent post.

LiftWatch.org is a news/portal site dedicated to following this and other developments in space elevators and related technologies. Besides the main front page news, here are some handy links for the SE afficianado:

• What is a "Space Elevator"?
• Links directory
• Concept artwork

I've been trying to get Slashdot to add LiftWatch headlines as an RSS feed. If you find the site interesting, please let the /. editors know so that there can be a LiftWatch.org slashbox.

The nanotubes are sticky and bond well with themselves. Read the article.

While this is true, for a sufficiently strong composite material we will also need the nanotubes to bond well to the substrate polymer. Although CNTs are attracted to each other, they tend to have featureless, smooth surfaces that don't bond well with other materials. The likely solution to this problem is a process called 'functionalization' which adds features -- small appendages -- to the CNTs so that there is more traction within the substrate. More work is required here, but some recent developments are encouraging.

As another poster has pointed out, you are arguing on out-dated information. Let's look at each point in turn.

Even if they could make carbon nanotube strands longer than 10 microns

Individual CNTs have been manufactured up to lengths of several centimeters at least. This article is from May of last year, and progress has been made since then. This is not thousands of kilometers, of course, but it does not need to be, since we're going to be using CNT composite materials rather than pure CNTs.

and even if they could braid them in a fashion where they wouldn't slip

We have been able to manufacture CNT composite materials on the order of meters in length with strengths on the order of several GPa's now for a couple of years. Currently, steady progress is being made to increase the strength of the composites to the required ~100 GPa.

they'd still have to launch a few thousand tons worth of stuff into geosynch orbit

Try about 100 metric tons placed in LEO. (Here's a reference for an older deployment strategy that comes in at 122,000kg.) Hubble weighs 11. Mir was more...

And then they'd have to figure out how to avoid getting the tether cut by space debris

This is the hardest problem, but not insurmountable even within a couple of decades. The ribbon will be made very resilient to micrometeorite damage. (Not saying it won't take damage... just that it will continue to work fine in spite of some damage.) For larger debris, it becomes considerably less likely to collide with the ribbon, but active avoidance will be used to move the ribbon out of the path of larger pieces of junk. Also note that once one ribbon is up, the cost of raising a second one lowers dramatically. The first order of business for SE1 will be to raise the components for SE2...

There is some serious research going on here, and it's looking very encouraging. See LiftWatch.org for regular news, links to research and companies, discussion forums, images, etc.

Carbon nanotubes and the idea of using lasers to do work both hearken to another up-and-coming scientific advancement destined to save humankind: the Space Elevator!

LiftWatch.org

I've put in a request... hopefully our headlines will be added as a slashbox here soon.