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Space Science

Space Elevators Going Up 473

MikShapi writes "CBC is running a new piece on the Space Elevator. Nothing dramatically new, as we're all still waiting for one of the many Carbon Nanotube research centers to announce they reached the famous 100GPa red line from page 10 of the NIAC Phase 2 Report, thus obtaining 'unobtainium' [pun intended], the material necessary to build the Elevator. The report predicts this will happen during the course of the next two years or so. It's then that the fun really starts - A REAL all-out space race, open to everyone with will and a national budget, winner probably getting to own space [read last paragraph]. In the meanwhile, we can all spread the word, discuss, debate and brainstorm every nook and cranny of the program here on Slashdot, and give Edwards a shoulder by giving the program every bit of mass-exposure we can."
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Space Elevators Going Up

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  • Top floor.. (Score:5, Funny)

    by Anonymous Coward on Friday February 27, 2004 @10:17PM (#8414178)
    Weightlesness, radiation, and hard vacuum.
  • by Anonymous Coward on Friday February 27, 2004 @10:17PM (#8414179)
    Will they have emergency override controls on the cargo deck? Watch 'Aliens' if you don't understand why this is necessary.
  • Doubtfull (Score:5, Insightful)

    by Smitedogg ( 527493 ) on Friday February 27, 2004 @10:18PM (#8414186) Homepage

    A REAL all-out space race, open to everyone with will and a national budget, winner probably getting to own space

    I predict that there will not be a space race, because the cost-benefit isn't acceptable yet. If this technology is only 2 years away (doubtful again), then there would be massive funding to accelerate the program if there was enough interest. Lack of interest now means that there is probably not going to be much interest when the nanotubes arrive.

    Dogg
    • Re:Doubtfull (Score:5, Insightful)

      by houstonbofh ( 602064 ) on Friday February 27, 2004 @10:27PM (#8414224)
      There will be funding just as soon as it looks like someone else could make it. No one will want to be the president who "Lost space to the Chinese." Embarrassment is a powerful motivator.
    • Re:Doubtfull (Score:5, Informative)

      by stealth.c ( 724419 ) on Friday February 27, 2004 @10:34PM (#8414263)
      Not two years away. More like fourteen. According to the article, it would be two years away once research has produced the proper technique for creating a cable, and once someone produces 650 tons of the stuff. Earlier in the article he mused that they were 12 years away from such a thing.
      • Re:Doubtfull (Score:4, Insightful)

        by AndroidCat ( 229562 ) on Friday February 27, 2004 @11:17PM (#8414428) Homepage
        And it would be nice to do a few trials first. Make a bridge out of it, put a few miles of it up in space. See how the stuff lasts over a couple years under various loads and conditions. A space elevator is a very messy thing to have an "oops" with.
      • by Anonymous Coward on Friday February 27, 2004 @11:40PM (#8414525)
        I can see the headlines in 2018 already:

        OPENING OF NEW SPACE ELEVATOR ENDS IN FIASCO
        During the official opening of the first space elevator
        a tragedy happened when the president was asked
        to "cut the ribbon". This prematurely destroyed the
        twenty billion dollar project, sending a rock with a
        100,000 km long ribbon attached to it into space.
        Read more on pages 2, 3, 4, 6 and 8.
        • Re:Doubtfull (Score:4, Informative)

          by linoleo ( 718385 ) on Saturday February 28, 2004 @05:38AM (#8415711) Journal
          sending a rock with a 100,000 km long ribbon attached to it into space.

          I do appreciate the joke, but if you were to actually cut that ribbon at ground level, all that happens is that the space elevator goes into a slighly elliptical orbit: the cut end of the ribbon ascends a few miles into the atmosphere only to come back down 12 hours later to pretty much the same location, where it can be snagged and re-anchored (same procedure as when the elevator is first lowered from orbit). A mishap for sure, but nothing more.
          • Re:Doubtfull (Score:5, Insightful)

            by jafiwam ( 310805 ) on Saturday February 28, 2004 @10:00AM (#8416376) Homepage Journal
            If you mean "pretty much in the same place" as in "on the equator" then sure.

            Though the orbit is geosynch, it isn't because of the distance of the center of mass of the thing. It's the distance of the center of mass of the thing while tied to the ground.

            Let it go, and it gets an elipitcal orbit that is NOT geosynch, and the thing comes back from it's elipical orbit somewhere else on the same latitude.

            Next, you are also assuming the thing does not have any "springyness" and bunch up on itself.

            Not a trivial problem.

            I bet you a taco dinner that if the cable gets cut on the ground it never comes back in a way that can be used.
    • Re:Doubtfull (Score:5, Interesting)

      by Jeff DeMaagd ( 2015 ) on Friday February 27, 2004 @10:55PM (#8414346) Homepage Journal
      One thing I really question is the claim that there will be or can be only one final winner in "owning" space. I'm sure there will eventually be wars and such but dominance by one group doesn't mean exclusion of another. There are times where one group in a particular realm is the "king of the hill" but often there is room for other players too, without the help of that "king".
      • Re:Doubtfull (Score:5, Insightful)

        by Jerf ( 17166 ) on Friday February 27, 2004 @11:42PM (#8414532) Journal
        If exponential growth predictions hold true, and the "first entity" locked out others from use, then the "first entity" would be a "winner" simply due to taking off too rapidly for others to feasibly catch up. That doesn't make the other entities "losers", except in relative terms; they may always be four years behind but that four years may represent a factor of, oh, as long as we're being fanciful let's say 50.

        However, I think there's a majorly false claim in there, which is that the first owner will lock out everyone else. Obviously, the first order of business when you have a space elevator is to put up more of them, and for a while they may indeed have a monopoly. But given the resources still available on Earth, someone will eventually tender an offer for a fully-completed cable that the first entity can't refuse; no matter how valuable the cable, it is possible to pay the owner off today with $X dollars, which the first entity will (correctly) perceive is more valuable to have it in liquid form, available to then invest back into other things. That price may be sky-high, pun semi-intended, but there are people on Earth who will be able to afford it.

        By buying a completed cable, they can jump-start themselves up, and as more and more entities do this, it'll start looking more even. While the first mover will have a true advantage that may last a very long time, I don't see a situation where they maintain a 20x advantage over everybody in perpetuity; the value proposition of liquidating one of the cables is just too appealing.

        This assumes a capitalistic owner of the first tether, and if the US gets there, the world can for once be glad that we see everything in terms of dollars, sooner or later, because that means that we will indeed have our price (though in the truest capitalistic tradition, it will be all the traffic can bear!). If it's not the US, well, it depends on who gets there first, but even so, it would take a very strong government to turn down the offers it would get... some of which are quite likely to be of the "offer you can't refuse" variety. ("Dear China: We still have nukes. Sincerely, All Nuclear-Capable Countries.") I still can't imagine a plausible long-term scenario where somebody maintains a massive, multiplicitave lead indefinately, though again, serious short- and medium-term advantage do accrue to them. (If nothing else, they'll need to draw on international capital to invest in space itself.)
        • Re:Doubtfull (Score:4, Interesting)

          by znu ( 31198 ) <znu.public@gmail.com> on Saturday February 28, 2004 @12:34AM (#8414755)
          From the other side, the idea that exponential growth will begin immediately after an elevator is constructed is probably total nonsense. There simply won't be that much demand. In a world where cheap access to space doesn't exist, nobody invests in things that demand cheap access to space. Once cheap access to space becomes possible, investment in such things will explode (probably to bubble-like proportions), but it will take years of R&D before the new stuff that will be created will actually be ready to load on an elevator. It takes time to build entire new industries up from essentially nothing.

          In any case, regardless of the economics, there are several countries which will want to have their own space elevators, simply for reasons of national security or prestige. The US would not be at all happy with the idea that China could cut of its reasonably-priced access to space, for instance. So, don't expect anyone to have an elevator monopoly for long.
          • Re:Doubtfull (Score:4, Interesting)

            by linoleo ( 718385 ) on Saturday February 28, 2004 @06:03AM (#8415755) Journal
            the idea that exponential growth will begin immediately after an elevator is constructed is probably total nonsense.

            That's correct, because the exponential growth will begin several years *before* the space elevator is operational, as soon as it looks like the project might actually succeed. Do you know how airplanes, satellite launches, RAM, and other items dependent on scarce, expensive manufacturing capabilities are procured? Companies purchase options for these things decades before they actually need them. In fact, much of the manufacturing capacity is *financed* through such options. Why would the space elevator be any different?

            nobody invests in things [that don't exist yet]

            *Investment* is by definition in things that don't exist yet. Otherwise it's called a *purchase*. Investors are very well capable of looking years ahead and weighting risk vs. profit.

            it will take years of R&D before the new stuff that will be created will actually be ready to load on an elevator.

            A communications satellite that goes to GEO by space elevator differs from one that goes to GEO by rocket only insofar as the former has to suffer far less g-forces on ascent and can therefore be built more cheaply.

            The US would not be at all happy with the idea that China could cut of its reasonably-priced access to space, for instance.

            Like they're not at all happy that China could cut off its reasonably-priced access to clothes, shoes, and electronics, for instance?
  • by zeux ( 129034 ) * on Friday February 27, 2004 @10:19PM (#8414190)
    Getting 100 GPa for carbon nanotubes composite is one thing. Getting 100 GPa on a 100000 kilometers carbon nanotube composite is another.

    I'm more interested in the length of the nanotubes than in their strengh since increasing the strengh is quite easy (basically all we need is to increase the fraction of carbon nanotubes in the composite) compared to increasing the length of the composite.
    • by liftwatch ( 731474 ) * on Saturday February 28, 2004 @02:13AM (#8415166) Homepage

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

  • Fwoosh! (Score:5, Funny)

    by Faust7 ( 314817 ) on Friday February 27, 2004 @10:21PM (#8414197) Homepage
    "If the whole thing fell somehow like you cut it at the counterweight, cut it way up at the counterweight, it would wrap around the Earth a couple of times," Laubscher says.

    Well, that's fine. Calculate the length of that sucker just right and you've got a quick, exhilarating way to travel from one point on Earth to another.
  • Huh??? (Score:5, Funny)

    by builderbob_nz ( 728755 ) on Friday February 27, 2004 @10:22PM (#8414207)
    thus obtaining 'unobtainium'

    OK for someone who can hardly remember a thing about High Scool Chemistry, Unobtainium, what's that? A new term for good karma?
  • by Faust7 ( 314817 ) on Friday February 27, 2004 @10:26PM (#8414221) Homepage
    In the post-9/11 world, the first space elevator, built by the United States, would be a tempting target for terrorism.

    Not if our brand-new Department of Homespace Security has anything to say about it!

    Imagine, if you will, a solid 3D column of security, with an outer edge in the shape of the U.S., starting at the U.S. and extending infinitely into space. I think if we tried, we could even make it glow the whole way. Put a scare into some of those E.T.'s.
  • by Anonymous Coward on Friday February 27, 2004 @10:26PM (#8414222)
    Almost exactly on the equator and above a lot of the weather.
    • If this is soon to become a reality (a large if, see my post below), than every nation on Earth is going to want to host it. Would Equador have enough standing on the world stage to pull this off?
      • by Anonymous Coward on Friday February 27, 2004 @10:51PM (#8414333)
        As far as countries on the equator go, Ecuador's competition consists of Colombia, Brazil, Sao Tome & Principe, Gabon, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya, Somalia, Maldives, Indonesia and Kiribati. I reckon they've got a shot!
    • by brandido ( 612020 ) on Saturday February 28, 2004 @02:28AM (#8415231) Homepage Journal
      I think one of the places that they are currently considering is just off Perth Australia. I am ont sure about Cayambe, Equador, but they are looking for an Ocean based anchor point for the elevator so that the base can easily be moved to help it dodge satellites and debris. Additionally, it needs to be in a region of low lightning activity and low hurricane/intense winds, as intense weather activity could threaten the elevator, particularly during early phases of it's construction. For some of the criteria that would be used to find a anchor location, check out Edwards report.
  • by ImTwoSlick ( 723185 ) on Friday February 27, 2004 @10:27PM (#8414229)
    It's nice that we're on our way to creating the materials needed for a space elevator, but where are we going to find a big enough rock to attach to the other end?
    • by Jeremi ( 14640 ) on Friday February 27, 2004 @11:38PM (#8414510) Homepage
      where are we going to find a big enough rock to attach to the other end?

      According to the book, the plan is to send up a rocket with the smallest possible cable. The cable gets lowered to Earth and secured (cable also gets spooled out in the opposite direction, in order to keep the spacecraft in orbit). Then they send up a series of progressively larger robots along the ribbon. Each robot adds more material to the ribbon as it climbs, and when it gets to the top of the ribbon, it stays there to add to the mass of the counterweight. So basically we bootstrap our way up.
  • by ThomasFlip ( 669988 ) on Friday February 27, 2004 @10:28PM (#8414231)
    When this technology finally comes into fruition, would it not basically put the ISS out of buisness ? You could basically do all of the things the space station does but also be able to lift and unload new cargo without launching rockets. And if this technology is only 2-3 years away, won't this be ready before the station is even built ?
    • When this technology finally comes into fruition, would it not basically put the ISS out of buisness ?

      One should hope so, shouldn't one?

    • by Honor ( 695145 ) on Friday February 27, 2004 @11:30PM (#8414482)
      The station is not only intended for putting things in orbit or for cargo purposes, but also for experimentation. The space elevator can only get the stuff/people up into space, but without a place to put them they arn't much use. Therefore, the ISS is still just as important as it was before, maybe more so. With the ability to more cheaply and easily get experimentation materials to the station, experimentation in space will become cheaper and more widely available. Perhaps with this new space elevator students can even go beyond the "vomit comet" and actually go into space. One easily accesible space station will inevidabley lead to others, soon.
      With the competition that all of this new technology is/will be producing, a commom point like the ISS is important to unite the major countries.
      • by ColaMan ( 37550 ) on Saturday February 28, 2004 @12:12AM (#8414643) Homepage Journal
        Except of course that the cable is stationary from the surface of the earth all the way up past geosync orbit (30,000k's).

        The ISS however, is moving at about 6-7km/s, in a different orbital inclination, barely a few hundred k's up. Getting material from the elevator to the ISS is going to be rather tricky.

        I hope they've done all the sums involved with regards to moving the base of the cable around a bit, wouldn't want it to get severed by a LEO satellite.
    • by Keith McClary ( 14340 ) on Friday February 27, 2004 @11:56PM (#8414565)
      You could basically do all of the things the space station does

      What does the Space Station do?
  • by TheKidWho ( 705796 ) on Friday February 27, 2004 @10:28PM (#8414232)
    Second Floor Scottie!!
  • by ObviousGuy ( 578567 ) <ObviousGuy@hotmail.com> on Friday February 27, 2004 @10:29PM (#8414236) Homepage Journal
    Whenever a space story is brought up, some person always brings up the argument that perhaps we should spend money on the poor instead of a useless space elevator (or whatever the space story du jour is). I don't think they are arguing correctly. Space is just as important to human advancement as feeding the hungry, curing chronic diseases, and providing a livable environment is. I don't think you can order these in importance, they are all important.

    But they go hand in hand with each other. Unless we truly believe Matthew 5:5, that the weak will inherit the Earth, it will take a worldwide view of humanity to move us to the next stage of human advancement which is the eventual separation of humans from the Earth and into the galaxy. We can go this alone, leaving the world's poor to their own devices, while the space superpowers leave them behind. However, when the day comes that certain small groups of humanity take to the heavens leaving this world and venturing off into the depths of space, how will history treat those of us living now who failed to hold the hands of those unable to stand with us as we raised humanity to new heights?

    The space elevator is a great achievement. Hopefully we will begin to have a true space-based space program that is not dependent upon sending rockets to the space station. This would be the largest step in the path to Earth separation since the first manned space programs.

    However, taking steps only with our strongest leg means we are still limping. We must strengthen all our limbs as members of the human family, IMO.
    • by homerjfong ( 709647 ) on Friday February 27, 2004 @10:48PM (#8414313)
      Warren Buffet often argues that since he is more productive than average, it's better for him to put his money to work than donate it to the needy. Once he dies, the argument goes, the money (a greater sum due to compounding) can be distributed. Take any discovery expedition - Columbus, Cortez, Polo - figure the aggregate value gained vs. the actual cost. This is the principle of investment.
    • Although I agree that the poor and hungry should be helped, humananity doesn't seem mature enough to help them yet. It's too bad really.

      Think of all the fuss made about the outsourcing of jobs. These jobs are a perfect way for Indians to earn money and rise above poverty. That is way people should be helped: give them an oppurtunity. Instead, people (such as prospective presidents) are trying to eliminate this! *sigh*

      Then there is this War on Terror business. Although many people will argue that it w
    • Actually, common English translations of Matthew 5:5 state that the MEEK shall inherit the Earth. Additionally, the evolution of the english word "meek" since the time of translation makes it an unfit word for the intended meaning.

      A more accurate interpretation suggests that those who inherit the earth are exactly the opposite of weak. Instead, the "meek" originally intended was a word to describe a ready and willing warrior. My university's Bible professor likened it unto the steed of a knight. Eager for
      • by parc ( 25467 ) on Friday February 27, 2004 @11:24PM (#8414459)
        Instead, the "meek" originally intended was a word to describe a ready and willing warrior.

        Can you give me a reference for this? The OED has no mention of this inversion of meaning. The closest it gets is the primary obsolete meaning, "Gentle, courteous, kind. Of a social superior: merciful, compassionate, indulgent." (see http://dictionary.oed.com, subscription required).
      • by Valdrax ( 32670 ) on Saturday February 28, 2004 @12:26AM (#8414716)
        According to Strong's Concordance, the word in the original Greek is "praus" (latinized spelling) which means mildness of disposition, gentleness of spirit, or meekness. [blueletterbible.org] If this page doesn't load, go here [eliyah.com], type "meek" into the first line, submit, find Matthew 5:5 and click on the number 4239. This word is close to the modern Greek "praos" which also means "meek."

        In other words, Jesus was saying that the humble and mild-mannered will inherit the Earth. You can find this same word commonly translated as meek in 1st Peter 3:4. Also, if you look at the context of Matthew 5:1-13, the opening of one of Jesus's sermons, it's quite clear that he's saying that rewards await the humble and downtrodden. They "are the salt of the Earth" and there is not an aggressive or angry group among "the poor in spirit," "those who mourn," "the meek," "those who hunger for righteousness," "the merciful," "the pure of heart," or "the peacemakers."

        I'd be very surprised if Strong's Concordance was wrong on the issue given the context and the modern descendant of the word. I'd love to see some evidence for your professor's claims.
    • by 1u3hr ( 530656 ) on Friday February 27, 2004 @11:13PM (#8414410)
      Whenever a space story is brought up, some person always brings up the argument that perhaps we should spend money on the poor instead of a useless space elevator

      I'm sure that more is spent on any one of: cosmetics, fizzy drinks, cigarettes, SUVs, cocaine. If you're just talking about govt expenditure; at least 100 times as much is spent on the military.

      If access to space is much cheaper, the benefits to the world will be immense; though it'll take a few decades. Even back in the 70s when O'Neill advocated space colonies in the L5 orbits it was possible to make a case. With a much cheaper launch method it becomes compelling.

    • by Goldsmith ( 561202 ) on Friday February 27, 2004 @11:20PM (#8414443)
      Every stage of major social advancement throughout history has come as a result of increasing opportunity.

      Were it not for exploration and technological advancement, we would almost certainly still be living as serfs to some fuedal lord.

      When the US was founded as a large republic, many people thought it would never make it. The success of representative government has improved the lot of many people, and arguably, the poor of the entire world.

      Now, we are all at a standstill. There is no place for people to go who seek to try something new. There are no experimental governments anymore, and there are no nation-wide experimental social systems. Individuals or small groups fight to improve the world, but there's nothing to be done against the inertia of the status quo. Things will improve, but slowly.

      Space offers that opportunity we need. Naive people see space as a playground for the rich. If we're going to have a playground, we're going to need to build it. The first people who will go permanantly up in a space elevator will be construction workers and engineers.

      When you take into account the resources available, and what it means for an end to mining and power production on earth, you have a pretty powerfull vision.

      It's remarkably short sighted to argue against taking ALL of humanity a step foward because we're not all on equal footing. We NEED to take this step foward, DESPERATELY, in order to help solve poverty, exploitation and many other ills in the world.
      • by NoData ( 9132 ) <_NoData_.yahoo@com> on Saturday February 28, 2004 @03:25AM (#8415416)
        We NEED to take this step foward, DESPERATELY, in order to help solve poverty, exploitation and many other ills in the world.

        With all due respect, I call bullshit. Your arguments and the parent post's arguments are simply so much sentimental claptrap.

        There's so much clamor for 'intellectual honesty' in the current political climate, let's start here.

        Let's call a spade a spade. Space exploration is worthwhile because we, as a society, have decided that the enrichment of human knowledge is a virtue per se. Knowledge for the sake of knowledge. Human endeavor. It needs no other rationalization.

        To say that space exploration is worthwhile because of unrealized, indeterminate side effects that are not the goal or intention of the pursuit, but held up, nevertheless, as some sort of social promisory note is just sophistic rhetoric. Tomorrow, I'll go tell the homeless guy down the street the good news: "Worry not, dear poor person, for we are building a space elevator that will elevate the dignity of all humankind, and so too shall your station rise!" Yes, and then I'll go tell the patients in the oncology ward that we shall cure cancer by building flying cars, for surely some modicum of the technology needed to build a flying car will make cancer fly from the body as well.

        Here's the thing: Multiple fronts. Society proceeds on multiple fronts. We don't stop space exploration because we have sick and poor people. We don't stop researching epilepsy because we have diabetes, stop researching diabetes because we have AIDS, stop researching AIDS because we have cancer, stop researching cancer because middle aged men have erectile dysfunction. What we DO do (giggle) is engage in a torturous debate in resource allocation. In terms of real life application, space exploration is an incredibly expensive, high risk investment with a possibly high payoff potential on a very far time horizon. But in the short term, we learn a lot about how the world works. This does improve the human condition in some abstract sense, but to say that it is a necessary step to curing some of our pressing social ills is disingenuous. The way to address our pressing social ills is to, you know, address our pressing social ills. We just have to figure out how to do that in a responsible way and still leave enough money over for the purer, less immediately tangible pursuits that we collectively value. Doing this factor analysis well is the hallmark of good government.

  • Two books... (Score:5, Informative)

    by Aardpig ( 622459 ) on Friday February 27, 2004 @10:29PM (#8414238)

    The Fountains of Paradise by Arthur C Clarke and Red/Green/Blue Mars by Kim Stanley Robinson. Both discuss the politics and sociology surrounding the construction and use of a space elevator. Good books, well worth a read.

  • by MajorDick ( 735308 ) on Friday February 27, 2004 @10:29PM (#8414240)
    Look for the AFL/CIO to get in on the act, Can you imagine how much money you could hide/steal/launder on a construction project of this size !
  • by jabberjaw ( 683624 ) on Friday February 27, 2004 @10:30PM (#8414244)
    In the article they estimate that it would require 650 tons of material. Christ, how many kilograms have we made to date! A two year timeline is unreasonable given our current limitations. Yes, it would be nice if we did have a space elevator, however I do not see it becoming a possibility in this decade. Do we not need more expertise in manufactoring and manipulating these materials? Has anyone made any mathematical models that predict the stress etc... that an elevator would need to undergo?
    • by zeux ( 129034 ) * on Friday February 27, 2004 @11:07PM (#8414386)
      It's amazing, it reminds me of the Manhattan Project.

      At the time the scientists were looking to get enough Uranium (238) and Plutonium to build the bomb. Everything else around was ready but they were producing only grams of the required materials a week.

      In only 2 years they improved the production quality and quantity dramatically to levels they didn't even dreamed of before.

      That's when they understood that what they though was granted long before (the 'rest' of the engineering needed for the bomb) was the actual hardest part to 'build'.

      Maybe this will happen to the space elevator with the nanotubes.
    • by afidel ( 530433 ) on Friday February 27, 2004 @11:09PM (#8414399)
      Well Buckminsterfullerenes were origionally VERY rare and hard to make. Then the carbon arc method using high pressure rare gas atmosphere was developed and suddenly they were abundant. Hell I made such a device for my senior year independant study program in high scholl back in 1996-7. These would typically make a fairly high percentage Buckyballs in the soot but I don't think many buckytubes, I assume they are waiting for a similar process for making buckytubes.
  • Bouyant cables! (Score:3, Interesting)

    by t0qer ( 230538 ) on Friday February 27, 2004 @10:30PM (#8414247) Homepage Journal
    Dang, over 300,000 geeks on slashdot and i'm the first to say this!

    Why not create a chain of bouyant cables [slashdot.org] instead of focusing on strong and light ones made from carbon nanotubes??
    • Re:Bouyant cables! (Score:4, Insightful)

      by Anonymous Coward on Friday February 27, 2004 @10:42PM (#8414293)
      Bouyant cables, even in the best case, can't get you out of the atmosphere, so maybe 1000 km on the top side. The space cable has to reach geostationary orbit, some 35,785 km out. You lose :)
  • by Gavin Scott ( 15916 ) * on Friday February 27, 2004 @10:32PM (#8414255)
    I was at that NIAC conference a couple years ago when Brad Edwards presented his Phase 2 results and I have to say this was one of the most inspiring things I've ever seen.

    Listening to him go through all the numbers and technical details you're left not only with the amazing scope of the thing but the feeling that, ya know, we might just be able to build this thing!

    G.

  • by cmason ( 53054 ) on Friday February 27, 2004 @10:33PM (#8414259) Homepage
    Just when you think all the great ideas have been thought of, scientists dream up a concept so radical, and so innovative, that you wonder if they've been smoking reefers the size of Yule logs.

    Such is the case with a group of scientists from the National Research Laboratory in Los Alamos, N.M. (''Los Alamos'' is Spanish for ''More than One Alamo''). According to an Associated Press story that I am not making up, these scientists are proposing to build an elevator that would be 62,000 miles high. That's right: 62,000 MILES, which is 32 million stories. At the top would be a revolving restaurant serving what the scientists promise will be ''really mediocre food.''

    - Dave Barry [miami.com]

  • test planet (Score:4, Funny)

    by way2trivial ( 601132 ) on Friday February 27, 2004 @10:34PM (#8414264) Homepage Journal
    would a mars elevator require a longer or shorter ribbon?

    build one there first maybe?

  • by blcamp ( 211756 ) on Friday February 27, 2004 @10:34PM (#8414265) Homepage

    Can you imagine making love in THAT elevator?

    Talk about Mile High Club...

  • don't be so quick... (Score:5, Informative)

    by Goldsmith ( 561202 ) on Friday February 27, 2004 @10:36PM (#8414271)
    I'm a physicist, and I work with carbon nanotubes. In October's Macromolecules, there was a paper put out called "Phase Behavior and Rheology of SWNTs in Superacids". It was done by a huge group of people (for a nanotech paper), including Nobel winner Richard Smalley. A press release about it was posted here somewhere.

    To make a long story short:
    They did it.

    By finding a way to dissolve nanotubes, then slowly concentrating the solutions, they formed a liquid crystal of nanotubes. By extruding this through a syringe, they formed an aligned, macroscopic, nanotube rope.

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

    What's left?
    They used tubes grown by high pressure carbon monoxide, which leads to a lot of defects. If they switch to methane, the defects will largely be gone, but the yeild drops.

    They probably need to chemically connect the tubes. You can do that with an electron beam, but that would be a pain industrially. I'm sure there's a way around it.

    I'm sure that same group of people has already figured out many more problems and solutions than I can think of. I havn't seen anything out about the mechanical properties of these ropes yet, but I would expect something within a few months, and I would be surprised if it wasn't amazing.

    I used to be a skeptic when it came to a space elevator, but now...
  • by MajorDick ( 735308 ) on Friday February 27, 2004 @10:43PM (#8414297)
    2 Things, Here in Akron Ohio, the Now home of Televangelist Earnest Angley, the building he now offupies was televangelist Rex Humbards previously, Rex started to build a HUGE Rotating restraunt on a pillar, something along the lines of the "space" needles, He ran out of Money before he could finish, so now at one of the highest points of town, a large white tower stands with no purpose, everyone here calls it Rex's Erection

    A second note that almost killed me with laughter was , well let me start with I used to be in the building trades, one day while at a supply house, a New blue truck pulled up, the sign on the side ? "Short STEEL Erection" I was dying, they specailzed in Steel reinforced concrete. I always love that one I think they were out of Canton OH
  • by Jartan ( 219704 ) on Friday February 27, 2004 @10:46PM (#8414307)
    Im constantly amazed how optimistic some people get about a space elevator. The main post and a lot of things other people are saying make it seem like they think technology is the deciding factor in whether or not one will get built. The only reason nobody has really spoken out against the idea is the average person thinks the scientists are smoking some good crack on this one.

    This isn't a harmless piece of cable we're talking about. The real barrier is going to be whether or not it'd be dangerous if it breaks or if it's cut. If it'll burn up and IF the burnt nanotubes aren't dangerous then maybe there will be a snowballs chance in *$#@ that the public will ok such a project. You can be guaranteed that if it's dangerous though that everyone will just assume that it will break or be broken intentionally.
    • The real barrier is going to be whether or not it'd be dangerous if it breaks or if it's cut.

      I remember reading about this concern somewhere. The idea was that the carbon nanotubes would be stretched almost as thin as paper. Should the ribbon break all that would happen is the ribbion would float back to Earth like paper and no one would get hurt.
  • by Anonymous Coward on Friday February 27, 2004 @10:46PM (#8414308)
    the top floor would move much faster than the bottom. Don't remember all my freshman physics, but it seems reasonable that to get to the top you have to undergo some serious lateral acceleration.

    You'd also have a hard time interacting with any orbiting satellites (except those in a geo-stationary orbit) because they'd be flying by at 13,000 mph.

    "We have to fix the satellite. Here it comes, I'll grab it with my giant catcher's mitt... WHOA! That almost took my head off! Well, at least it won't come around again for 90 minutes."
  • by GarbanzoBean ( 695162 ) on Friday February 27, 2004 @10:48PM (#8414318)
    The strength of the material is controlled by defects. In a petri dish, the carbon nanotubes have no defects, but there is no way they can make a cable that is more than a few cm long without defects. This will make the strength of carbon nano-tube much smaller. In real materials, the reductions is 3 orders of magnitude. So instead of a meter wide cable, they would need a kilometer wide cable.
  • by Anonymous Coward on Friday February 27, 2004 @10:59PM (#8414357)
    ...the 100 GPa number sounds ridiculous.

    For context: the most common type of structural steel currently used has a yield strength of 350 Mpa. 100 GPa is 285 times stronger. And stronger isn't enough, it has to be dependable and resistant to cyclicle loading and fatigue, which isn't easy to quantify, especially under such unusual conditions.

    To suggest that this can be achieved in a couple of years sounds silly to me, considering whatever material used would a lengthy term of testing and a proven track record before sinking billions of dollars into it.
    • by Goonie ( 8651 ) * <<gro.arbmaneb> <ta> <lekrem.trebor>> on Friday February 27, 2004 @11:40PM (#8414526) Homepage
      the 100 GPa number sounds ridiculous.

      For context: the most common type of structural steel currently used has a yield strength of 350 Mpa. 100 GPa is 285 times stronger.

      Yes, it sounds outrageous, but it's theoretically possible to do this with nanotubes, apparently. As I understand it, nobody has actually demonstrated a macroscopic piece of nanotube composite with this kind of strength though.

      To suggest that this can be achieved in a couple of years sounds silly to me, considering whatever material used would a lengthy term of testing and a proven track record before sinking billions of dollars into it.

      True, but the things made possible with such a material would surely attract billions of dollars worth of R&D. Can you imagine what it could do for things like aircraft design?

  • My prediction (Score:4, Interesting)

    by Mantorp ( 142371 ) <mantorp 'funny A' gmail.com> on Friday February 27, 2004 @11:02PM (#8414374) Homepage Journal
    It'll be at least a century before one of these things actually do anything useful.
    • Re:My prediction (Score:5, Insightful)

      by mcrbids ( 148650 ) on Saturday February 28, 2004 @01:11AM (#8414910) Journal
      It'll be at least a century before one of these things actually do anything useful.

      What's sad is that it may well take that long.

      However, the best thing we could do to promote the sky elevator is to develop and build nonotube-based structures here on Earth.

      For example, if you were to rebuild the Golden-gate bridge in San Fransisco with nano-tube cables instead of steel cables, would they even be visible from the shore?

      An impressive, previously infeasible structure, such as a bridge spanning the entrance to the Mediteranean, or across the English Channel would do much to get everybody used to the idea that something like this could, in fact, be done.

      Also, projects like this would give us opportunities to answer questions about its durability, relability and safety in a large number of circumstances.

      Building a space elevator with nanotubes as the first project is fundamentally stupid. Build something more reasonable first!
  • Hmm (Score:5, Insightful)

    by ShooterNeo ( 555040 ) on Friday February 27, 2004 @11:13PM (#8414414)
    One question : the basic plan involves transmitting power through microwaves or laser light, enough electric power to provide the kinetic energy difference to actually put a vehicle in orbit. Why not skip the development of unobtainium and skip trying to put a super long and heavy cable in orbit? Just build the power laser facility 10 times over, and build spacecraft that use a block of inert propellant, heated to millions of degrees celcius from pulses from the laser and pulsed such that the shockwave is a planer wave coming away from the spacecraft. So no nozzles, no rocket engines, no pumps, no chemicals, no fuel, no explosives...all the stuff that make spacecraft expensive and dangerous. Just a block of cheapo rock and a spacecraft built like a cheap copy of an Apollo capsule made by the Russians. Would be safer as well, since in-orbit is pretty safe (there are patches to plug small holes), launches no longer can blow up, and reentry is much simpler and less error prone that with a space shuttle. Finally, that kind of laser would make a rather fine weapon, and would help out military applications as well (so could get some of the funds from the U.S. military budget)
  • by whorfin ( 686885 ) on Friday February 27, 2004 @11:18PM (#8414433)
    1/625 possibility of 'severe damage' (aka destruction) from the 2031 Leonid Shower is a pretty damn big risk, if you ask me. I imagine that every nation that might get smacked by falling debris would have an objection to this ever going up on this basis alone.
  • Why individually? (Score:4, Insightful)

    by Alizarin Erythrosin ( 457981 ) on Friday February 27, 2004 @11:18PM (#8414434)
    Instead of each nation trying to build it in competition, why don't we try to build it all together? Maybe this is the event we need to unite as a world, Star Trek stylee...
  • by btempleton ( 149110 ) on Friday February 27, 2004 @11:23PM (#8414454) Homepage
    At least if you found yourself caught with a VC in this elevator, you would finally have time to really pitch your business plan.

    On a serious note, they predict it would be hit, if not moved, by a large space object around once a year. They think they can spot these objects and move it as needed. But what about smaller objects. How much damage will they do? How easily can they be detected? How often will they hit?

    And worse, what about deliberately launched smaller objects, radar-invisible small objects fired by a nation that doesn't want another nation to own space.
  • Economics (Score:4, Interesting)

    by bremstrong ( 523910 ) on Friday February 27, 2004 @11:45PM (#8414539)
    The only problem is that the same nanotube technology that would enable a space elevator will also enable a reusable single-stage-to-orbit spacecraft capable of putting mass into orbit at a much lower cost.

    Just to pick some numbers:

    Space elevator: $5B each, one 4 ton payload per day

    Nanotube composite rocket: $.1B each, one 8 ton payload every two days

    In other words, it will never happen.
  • A WEEK?! (Score:3, Insightful)

    by tuxedobob ( 582913 ) <tuxedobobNO@SPAMmac.com> on Friday February 27, 2004 @11:45PM (#8414540)
    Cripes, these ships are probably going to be pretty small, aren't they? And there won't be much to do? And it's going to take a week?

    I wonder if there's any chance that it could use a maglev system. Japan's at 581kph or so. If you could fly straight up at even 500kph that cuts the trip down to 3 days.
  • Cost (Score:5, Insightful)

    by Moderation abuser ( 184013 ) on Saturday February 28, 2004 @02:36AM (#8415260)
    I predict that a space elevator will make the cost of the lunar landings look like peanuts. I very much doubt it'll happen in our lifetimes.

    NASA is the reason space is expensive. Companies like Starchaser and Scaled Composites are the ones who will make space cheaper and will "own space".

  • by klic ( 739114 ) on Saturday February 28, 2004 @02:47AM (#8415311) Homepage
    I've fiddled with the math for these kinds of things for decades on an old idea called the "launch loop". The dynamics of long tapered cables are not impossible, but they are nasty. Very long cables are not like a stout rope to a fixed point nearby, they are more like reaction mass that vibrates. Think "Tacoma Narrows Bridge", which fell down because 1930's engineers did not take their differential equations up to 7th order.

    As a climber goes up, the surface anchoring system must pay out more cable to fill in the less tensioned region under the climber, faster and faster as the climber accelerates up the cable, proportional to the speed of the vehicle, total acceleration (including gravity) and inversely proportional to the mass per meter and the square of the propagation velocity of the material.

    This is continuously changing, so forces and velocities at the surface are changing also. The problem is, this is an underconstrained and essentially undamped end-terminated system - as the cable gets very long, you develop big standing wave complexes with only two points (surface and top anchor) to remove or store the energy. Keeping the standing waves from building up is difficult, but not impossible. However, it does add an additional constraint on launch rate; you have to spend a lot of time damping out the waves, even granting that these people are more clever than I am at modelling and removing this energy.

    Tapering of the cables, necessary even with magic nanotube unobtainium, makes the math even more "exciting", with the additional constraint that the through-atmosphere sections, along with the sections that dip into the atmosphere during wave motion, have to be thoroughly protected against atmospheric degradation (hint: C + O2 -> CO2 ). The portions of the system below the Van Allen belt have to be armored against atomic oxygen damage. Atomic oxygen will burn off the leading edge of ISS at rates approaching a millimeter per decade; the space elevator will be stationary in the gas field, but there are still a lot of fast moving oxygen atoms up to, and through, the radiation belt.

    All motor driven systems have limits to their power-to-weight ratio. To get to GEO, we have to add about 60MJ/kg. If we take 33 hours to do so, we need to move an average of 500 watts per kg (total climber weight) through the (photovoltaic or microwave) energy collectors, motors, rollers, etc. For comparison, a 1500 kg sports car with a 300 horsepower gasoline engine uses 150 watts per kg. However, that underestimates the problem. Most of the energy will be added at the beginning of the climb, during the first 10% of the travel distance, as the climber leaves the depths of the gravity well, so expect thousands of kilowatts per kilogram in the power train during this phase. If there are unexpected variations in the power, the change in climbing acceleration will add more ripples to the cable.

    I tried to avoid these problems with the launch loop (see URL below) by keeping the altitude under 100 km and the motors on the surface. Even over those "short" distances, cable propagation issues are problematic. Funny/bad things like lightning, ice buildup, fractally gusty winds, and jittery payload forces require special attention, and all reduce the capacity of the anchoring and stability cables. Everything above the atmosphere is exposed to a steady rain of the garbage that your launch system has accumulated in orbit (it all comes down, eventually). Reentry systems for human payloads (in case of failure) add weight. Problems, problems.

    At the end of the day, though, the killer issue is lack of demand. The launch loop, with about the price as a space elevator (+/- 3dB) and using materials and technologies we have had for two decades, can put 80 tonnes of payload into orbit *per hour*, for less than $10/kg. Unfortunately, nobody wants that much mass in orbit, even at that miniscule price. Perhaps "if you build it, they will come", or perhaps you end up with another white elephant lik

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