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I'd post this here because it is a way of getting us out into space, even as a sort of interplanetary propulsion.
I saw this article
http://www.yomiuri.co.jp/dy/features/sc … Y02006.htm
an article about some more nanotube work that increased nantube purity by like 97 percent! And! They can already roll out nanotube sheets meters long, so, I decided to go look for some of the latest news on space elevators; the link given shows some pretty good stuff including an entertaining countdown meter!
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Interesting... but how perfect and well alligned are these tubes I wonder?
Sounds too good to be true.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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i'm affraid I don't know all the latest results on nanotubes well enough to exactly say where they are in making bulk nanotube materials, even if I put in 'nanotube alignment' or something like that in yahoo or google; i'd say ask Liftport! They probably monitor the state of the art much more closelly than I there.
But! As I've mentioned, I remember seeing video of some kind of nanotube sheet maker that spat out about two or three meters of plastic sheet looking nanotube material in a few minutes time(this seems almost years ago now), so, they have the nanotube alignment problem down to some pretty good degree.
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The Space Show recently interviewed Michael Laine, CEO of LiftPort, he discusses the current state of art and his future plans.
Bottom line: the elevator ribbon needs to be about 100 GPa, currently available materials are about 6 GPa, some way to go.
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well, 97 percent increase in nanotube purity got to put a pretty good dent in the materials problem for space elevators.
As for the statistical calculation that space elevators will be impossible to build, I just saw a spacedaily article about genetic algorithms being used on nuclear propulsion; certainly, advanced computing can be used on controlling the making of the space elevator ribon; if it turns out to need that much computing, what a technological marvel the space elevator will turn out to be!(yes, i view technologies as precious and the more marvelous the better! I have my own rationality about it all, but it seems to be all my own!)
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Just as long as it is CaLV that lifts Liftport--I'm happy.
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Bad news for the space elevator.
Pugno's calculations show that inevitable defects in the nanotubes mean that such a cable simply wouldn't be strong enough.
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Bad news for the space elevator.
Pugno's calculations show that inevitable defects in the nanotubes mean that such a cable simply wouldn't be strong enough.
Well why are the defects inevitable? And even if we don’t reach 60 GPA why can’t the cable be tapered?
Dig into the [url=http://child-civilization.blogspot.com/2006/12/political-grab-bag.html]political grab bag[/url] at [url=http://child-civilization.blogspot.com/]Child Civilization[/url]
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Well why are the defects inevitable? And even if we don’t reach 60 GPA why can’t the cable be tapered?
The cable will have to be tapered anyways. The problem is if you don't reach 60 GPA the amount of taper you need at the top cannot be large enough to support the bottom. Remember that mass scales with the cube while strength only scales with the square.
However I'm not sure that these pessimistc observations mean the end. New methods of creating nano-tubes may be discovered that have lower defect rates. New methods of creating mass bundles of long nano-tubes need to be developed in anycase. OR new quality control methods may be developed that can eliminate the defects may be discovered. OR it may turn out that the rate of defects is low enough that sufficent amount of the nano-tubes strength may be transfered to the bundel at large making the defects irrelevent. His studies seems to indicate that this will not be the case, but I am sceptical, and would have to read the paper to be convinced. OTOH, this is not my area of specialty and it evidently is his.
He who refuses to do arithmetic is doomed to talk nonsense.
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Abstract and full text of Pugno's paper here
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Carbon nano tubes have a density of 1300 kg per m^2 which is somewhere between the gold and green line on figure 2 on:
http://www.liftport.com/papers/2005Nov_ … n_Mass.pdf
From the graph it appears that a carbon nanotube cable with 60 gpa strength, a factor of safety of 2 and a one ton lifting capacity would way in total 300 tons. Now if the elevator could lift that 1 ton of mass up and down the elevator more then 30 times a year (or about 3 times a month) it wouldn’t be too long before the cost of mass to orbit would fall to the marginal operating cost of the elevator.
Dig into the [url=http://child-civilization.blogspot.com/2006/12/political-grab-bag.html]political grab bag[/url] at [url=http://child-civilization.blogspot.com/]Child Civilization[/url]
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usually, when a theoretical crisis like this is presented, an innovative solution is found which speeds the whole development;
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With the most recent discoveries and attempts to use the buckball as a storage medium of hydrogen I began to wonder if there were other ball structures that could be made to create the elevator as well.
Buckyballs Make Room For Gilded Cages of gold (Au) it requires many fewer--16, 17 and 18 atoms, in triangular configurations more gem-like than soccer ball than carbon c60.
Are there other formations, that only in time will lead to a lowering of cost to access space? One can only hope that it can be so.
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Just as long as it is CaLV that lifts Liftport--I'm happy.
We were excitedly watching the SpaceX progress in hopes that they'll lower our launch costs. The likelyhood of the US government being cost competitive with other countries or private industry seems unlikely based on their current and past performance.
Elon Musk, however, didn't seem to think about the fact that we may be a very large potential customer. In a recent interview by PC Magazine,
When asked about another possible way to get into space, the space elevator, [Chris Farnetta and Elon Musk] were dismissive. "The main component is made out of Unobtainium," joked Farnetta. Musk agreed. "We want to see a carbon nanotube footbridge," he warned, "before we see one 60,000 miles long."
That's not quite the attitude I would take with a potential buyer of between 6 and 9 Falcon 9 S9 launches.
As for Pugno's article, there's as many academics that disagree with him as agree with him. We are going to continue plugging along with the expectation that we will be able to build it. In the process, we're developing several new technologies that are becoming marketable products in the near term.
[url=http://www.liftport.com/store][color=#DD3333]If you have questions about the LiftPort Space Elevator, consider buying our book, [i]LiftPort: Opening Space To Everyone[/i].[/color][/url]
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Just as long as it is CaLV that lifts Liftport--I'm happy.
We were excitedly watching the SpaceX progress in hopes that they'll lower our launch costs. The likelyhood of the US government being cost competitive with other countries or private industry seems unlikely based on their current and past performance.
Elon Musk, however, didn't seem to think about the fact that we may be a very large potential customer. In a recent interview by PC Magazine,
When asked about another possible way to get into space, the space elevator, [Chris Farnetta and Elon Musk] were dismissive. "The main component is made out of Unobtainium," joked Farnetta. Musk agreed. "We want to see a carbon nanotube footbridge," he warned, "before we see one 60,000 miles long."
That's not quite the attitude I would take with a potential buyer of between 6 and 9 Falcon 9 S9 launches.
As for Pugno's article, there's as many academics that disagree with him as agree with him. We are going to continue plugging along with the expectation that we will be able to build it. In the process, we're developing several new technologies that are becoming marketable products in the near term.
Welcome to New Mars Joe!
We all expect great things of LiftPort and its elevator(s) as the the only real alternative on the horizon to chemical ascent from this gravity well.
Be wary of communicating via third party media reports, they do have a way of spinning what was said out of context merely to make headlines (never let the truth get iin the way of a good story)
It would be very helpful to know the academic rebuttal to Pugno's thesis about defects limiting the absolute strength of carbon nanotube ribbons.
BTW wouldn't the 120+ mT lift capacity of the CaLV be a better solution than messing about with several F9-S9 launches?
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
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It certainly would be. ISS proved the folly of piecemeal 20 ton at a time assembly.
I like the Mega-module approach--the one that was bashed by that know-nothing Ed Wright of the NASCAR rocket race scheme. The mega-module approach could have had ISS done in five flights--not five hundred, so to speak.
Bigger modules and less assembly. Not smaller modules and a whole bunch of headaches.
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Hmm.. I posted a nice long eloquent reply to cIclops but it looks like it never made it.
Our desire is to get the starter ribbon up in as few launches as possible balanced with as few dollars as possible in the timeframe we've set aside. Unless the government decides to subsidize our launches, it seems likely that private industry will be more able to satisfy our requirements. That doesn't, of course, rule out the possibility of using NASA.
If NASA can complete a project, the HLLV/CaLV might be a better option. The ISS, X-33, X-34, etc. don't give me a lot of confidence that the political spectrum won't change and scrap the entire project, however.
The goal of the HLLV design project is to build the next launch vehicle for the return to the moon (RtM). The RtM project was mandated by George Bush, the president with such an incredibly low approval rating that whoever follows him is going to have to disassociate himself (or herself) with any project they can poke fun at. There's enough diviciveness in the field of human space exploration that it seems as likely as not that the new president will cancel the RtM project and take NASA in a completely different direction. I hope that doesn't happen, but in a government administration, it's more about control and power than it is about science or desire.
Newt Gingrich has already spoken out against NASA's involvement in taking humans to space, and has instead proposed a series of prizes to continue to encourage private enterprise to take over the fulfillment of that need.
We will, of course, keep our options open and not burn any bridges. Our goal is to build the LiftPort Space Elevator, and as Michael Laine likes to say, "We don't even have all the questions yet, let alone all the answers."
We'll just have to wait and see.
[url=http://www.liftport.com/store][color=#DD3333]If you have questions about the LiftPort Space Elevator, consider buying our book, [i]LiftPort: Opening Space To Everyone[/i].[/color][/url]
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Newt Gingrich has already spoken out against NASA's involvement in taking humans to space, and has instead proposed a series of prizes to continue to encourage private enterprise to take over the fulfillment of that need.
Please--not that rot again. Griffin is an engineer--so where does that politico get off telling him his business? If you split money a thousand different ways you get a thousand different failures. Enough with the alt.space movement.
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Griffin is an engineer--so where does that politico get off telling him his business?
If he gets elected, the same way any boeing engineer gets told when to ship wing manufacture overseas - by the boss.
btw... I'm not pushing his agenda, nor have I followed usenet since the early 90s. His point-of-view, however, seems to oppose that of the President and that's probably good political posturing.
[url=http://www.liftport.com/store][color=#DD3333]If you have questions about the LiftPort Space Elevator, consider buying our book, [i]LiftPort: Opening Space To Everyone[/i].[/color][/url]
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It certainly would be. ISS proved the folly of piecemeal 20 ton at a time assembly.
I like the Mega-module approach--the one that was bashed by that know-nothing Ed Wright of the NASCAR rocket race scheme. The mega-module approach could have had ISS done in five flights--not five hundred, so to speak.
Bigger modules and less assembly. Not smaller modules and a whole bunch of headaches.
Ever read about the Sea Dragon rocket proposal? 550 tons to LEO. I think Truax had the design.
Sure people dream about space travel. There's nothing wrong with that. Everything humankind has made, was once but a dream.
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Hmm.. I posted a nice long eloquent reply to cIclops but it looks like it never made it.
Our desire is to get the starter ribbon up in as few launches as possible balanced with as few dollars as possible in the timeframe we've set aside. Unless the government decides to subsidize our launches, it seems likely that private industry will be more able to satisfy our requirements. That doesn't, of course, rule out the possibility of using NASA.
If NASA can complete a project, the HLLV/CaLV might be a better option. The ISS, X-33, X-34, etc. don't give me a lot of confidence that the political spectrum won't change and scrap the entire project, however.
Good to see you found the "Submit" button again
Besides overcoming technical problems, the elevator also has to prove its feasibity to attract funding. Other than the challenge competitions how do you intend to literally bridge the gap to a working demonstration? What would be the minimum size elevator?
<Off the wall idea> the first test flight of the CaLV might be an ideal low cost option to hang something up there .... 125 mT is a lot of ribbon
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
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Its got to go all the way to GEO though, so it will be a bit less then that. Probably in the 70-80MT region.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Our desire is to get the starter ribbon up in as few launches as possible balanced with as few dollars as possible in the timeframe we've set aside. Unless the government decides to subsidize our launches, it seems likely that private industry will be more able to satisfy our requirements. That doesn't, of course, rule out the possibility of using NASA.
Talking about timeframe, the guys from liftport mention on their website to get the first cable working by 2018. I find it hard to believe that finding a sufficiently strong cnt-composite-material and an efficient method for its production and building the infrastructure (factories, ocean platform, laser-systems etc.) can be accomplished in only 10 years. Timeframes of past space projects of comparable mass dimensions teach you that it will take much longer than that. So, Joe_LiftPort, how do you plan on getting the cable up and working by 2018?
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Hi Kaladasa: I'm inclined to agree, the 2018 date will likely slip eventually, but over optimism has it's rewards. We don't want people thinking they have lots of time to perfect the lifter or the anchor ship nor the big lasers, nor the 840 nanometer photovoltaic panel.
I'm urging a not very useful short slow rotovator of very thin tapered kevar ribbon with a thin coat of not very good CNT and a climber. This will test the laser and climber at LEO, and the transcients generated on the rotovator will give at least a clue about transient which are likely on the 100,000 kilometer ribbon. The climber can lay an almost worthless thread of CNT just to be sure the thread can be attached as expected. Neil
PS: I have absolutely no authority at Liftport, but I do post on their forum frequently. Neil
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Space Elevator Games to take place at the 2006 X PRIZE Cup in New Mexico
More than 20 teams are expected to compete for $400,000 at the Las Cruces International Airport on October 20-21, 2006.
"We are very excited to welcome the Elevator Games to the X PRIZE Cup," said X PRIZE Founder and Chairman Dr. Peter H. Diamandis.
Way to go X PRIZE Foundation ... its a start..
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