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Space Science

NPR Talks Skyhooks 328

Posted by Zonk from the beyond-the-clouds dept.
David writes "NPR's Talk of the Nation this past week featured Brad Edwards, President of Carbon Designs Inc., to talk about their plans to develop an elevator that would lift people to an object orbiting in outer space. The project's homepage details their plans and ambitions. The discussion expands on callers' concerns about such problems as commercial airliners running into the super long cable or if it would act as a conduit for lightning."
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NPR Talks Skyhooks More

NPR Talks Skyhooks

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  • Skyhooks? (Score:4, Funny)

    by imroy ( 755 ) <imroykun@gmail.com> on Sunday June 05, 2005 @05:40PM (#12731089) Homepage Journal
    Does the audio program mention the word "skyhook"?
    Why bring up the Aussie 70's supergroup [wikipedia.org]?
    • Does the audio program mention the word "skyhook"?
      If I recall correctly, the glass elevator in Willy Wonka and the Great Glass Elevator was powered by or held up by skyhooks.

      I suspect you already know this, but figured somebody else might not get the reference.

    • Re:Skyhooks? (Score:2, Funny)

      by pintomp3 ( 882811 )
      what does space have to do with kareem abdul jabbar?

      *reference may be lost on /.*

  • wrong concerns (Score:3, Insightful)

    by cryptoz ( 878581 ) <jns@jacobsheehy.com> on Sunday June 05, 2005 @05:41PM (#12731093) Homepage Journal
    Wow, our society has changed. The concept of airliners being uninformed of the location of these cables or whatever they are is just plain stupid. Of course they will know that they're there. Not to mention, even if they didn't know, the chance of a collision is fabulously small.

    People should be more worried about if this is the best way to spend money or not. Personally, I think it's a pretty sweet idea and I'd be totally for supporting it. Looks quite awesome, actually!
    • Not to mention, even if they didn't know, the chance of a collision is fabulously small.

      Unless the pilot is a crazed Saudi with a taste for Flight Simulator...

      • Re:wrong concerns (Score:5, Insightful)

        by bobetov ( 448774 ) on Sunday June 05, 2005 @06:02PM (#12731189) Homepage
        Please. Stopping the construction of fabulous new projects because they could be terrorist targets is defeatist at best.

        Besides, the very first use of the very first skyhook should be to build the *second* one. It only gets easier the more we do it, and boy, does taking an elevator beat strapping an explosion to your butt.

        Here's to audacity and dreaming big dreams.

      • Re:wrong concerns (Score:2, Insightful)

        by Jeremi ( 14640 )
        Unless the pilot is a crazed Saudi with a taste for Flight Simulator...


        And what if he is? The elevator is in the middle of a frickin' 4000 square mile no-fly zone. They'd see him coming for several hours before he got there. There would be loads of time to, um, dissuade him from his course.

        • How would a 4000 square mile no-fly zone give HOURS of advanced notice? 4000 square miles is only about 62 miles by 62 miles. You'd be 31 miles from no-fly to space elevator.

          Not that I am holding my breath on a space elevator or terrorists attacking it.

      • Re:wrong concerns (Score:3, Informative)

        by 1u3hr ( 530656 )
        Unless the pilot is a crazed Saudi with a taste for Flight Simulator...

        Sorry, this isn't "insightful". Need I say RTFA? Perhaps I do.

        • the elevator cable is a few mm wide, and thus invisible from any distance (though the climbers will be larger, but only a few times a day). Not an easy target
        • the base will be a platform on the equator in the open sea. It'll be well out of any normal flight paths, anything approaching will be very obvious a long time before it gets close.
        • it'll surely have air defence

  • The next x-prize (Score:5, Interesting)

    by maelstrom ( 638 ) on Sunday June 05, 2005 @05:41PM (#12731098) Homepage Journal
    Here is some money that NASA could "invest" in another x-prize like compitition. Get some innovation back into the space game. Maybe once China starts blasting some people towards Mars the US will get off its ass again.

  • Answer (Score:5, Funny)

    by Rosco P. Coltrane ( 209368 ) on Sunday June 05, 2005 @05:42PM (#12731101)
    From TFA:

    We firmly believe that the set of technologies that underlie the infinite promise of the Space Elevator can be demonstrated, or proven infeasible, within a 5 year time-frame. And hence our name. Elevator:2010. we promise to get an answer for you by then.

    Message 5 years from now:

    42

  • I just have to ask... (Score:4, Funny)

    by NotQuiteReal ( 608241 ) on Sunday June 05, 2005 @05:51PM (#12731136) Journal
    When the space elevator is built, just what kind of elevator music will it have?

    The longest song in my MP3 collection is 22:43 (Autobahn by Kraftwerk - even on topic, sort of...) Is that long enough for the ride up? How many quarters do I need to put in the slot?

    • The longest song in my MP3 collection is 22:43 (Autobahn by Kraftwerk - even on topic, sort of...) Is that long enough for the ride up?

      I think you're looking at something like Wagner's Ring Cycle instead. 18 hours sounds about right for a space elevator ride.

      How many quarters do I need to put in the slot?

      What the hell elevator do you ride that requires you to pay to get musak?? Personally, I'd pay to silence the damn thing...

    • Autobahn by Kraftwerk - even on topic, sort of...

      Hope they have enough barf bags ...

      Sex Objekt [progarchives.com] is much better Kraftwerk. Autobahn is just ... 22.72 minutes of boredom. (I've got that vinyl somewhere. ..)

      I may need to pull it out and hook up the turntable just to remind myself how bad it is, 31 years later. (It's from 1974, right?)

    • Thick as a brick by Jethro Tull. Not sure how long it is, but it fills both sides of a 12" LP
    • When the space elevator is built, just what kind of elevator music will it have?

      It's a Small World After All?

      *cringe*

  • Muzak (Score:3, Funny)

    by Anonymous Coward on Sunday June 05, 2005 @05:54PM (#12731150)
    According to the website, the elevator will move at 200 mph. Considering that our atmosphere is roughly 380 miles, I'm going to have to listen to Kenny G for almost 2 hours!
    • According to the website, the elevator will move at 200 mph. Considering that our atmosphere is roughly 380 miles, I'm going to have to listen to Kenny G for almost 2 hours!

      You're going to eat a lot more Kenny G. than that, since the endpoint would have to be in geosynchronous orbit, in order for the cable to stay taut and the station not to fall back on Earth.

      • Re:Muzak (Score:2, Informative)

        by evil_mojo_jojo ( 554131 )
        The endpoint is way past geosynchronous orbit, but the counterweight is less than the cable. It's a win because if you put the endpoint out far, you get greater centripidal force for an extra-orbital launch.
      • No. The end of the cable has to be in GSO, but your destination doesn't. You could go part way up, debark, transfer to a low-G shuttle and go visit something that is in LEO. There is no reason to be in GSO unless the station / satellite / destination has to hang over one point on earth all the time (and it'd be considerably less boring if a "space hotel" wasn't in GSO anyway.)

        Certainly the end of the cable has to be in GSO, but really, other than communications and weather/observation satellites, what els

  • kiddies beware... (Score:5, Funny)

    by moviepig.com ( 745183 ) on Sunday June 05, 2005 @06:01PM (#12731181)
    I guess the old prank of jumping onto a crowded car and pushing all the buttons would be a no-no...

  • Protection is a non-issue (Score:4, Insightful)

    by Profane MuthaFucka ( 574406 ) * <busheatskok@gmail.com> on Sunday June 05, 2005 @06:01PM (#12731183) Homepage Journal
    It always comes up, but protecting a space elevator is really
    simple to solve. Put the base in the ocean, and stick a carrier task force there to protect it.

    We already have an example to follow. Fort Knox has a tank combat training ground there, and plenty of tanks stationed there permanently. Good luck trying to raid the place.

    Terrorist attacks are dangerous because they could happen anywhere, but that doesn't mean that we can't make a single known place extremely secure from that sort of thing. If it is decided that no aircraft will approach within 100 miles of a space elevator, a single carrier task group could enforce that easily. Revenues from the space elevator would easily pay for the security force too, and it'll still be the cheapest way to get something into space.

    • Too true. Airliners can only go up to 50000 feet or so, well within the range of surface-to-air missiles. You don't even need a carrier, just a ring or two of cheap platforms with SAMs. Bad as it sounds, an investment on the scale of a space elevator would be worth killing a few hundred people over.
    • Of course, the same problem that Fort Knox would have still applies here, and more so - bring a car (suitcase) with a home-built nuke over, park it moderately close (close enough to be close, far enough away to not arouse suspicion), set timer for 24 hours, catch Greyhound bus (escape boat) to a location a few states away. Boomy. I suspect it would be harder on the elevator, but it also sounds more vulnerable to large-scale explosives than Fort Knox.

      Not like there's anything we can do about that.
    • It's easier than that. One space elevator is precious. Two are less so and the progression is geometric. Build a bunch OF them and your target problem is by and large solved.

      Once it's in service for a while, the 'new' factor is gone and it's just another large structure, less suited for a terrorist target than most. No one really sweats a terr attack at Johnson Space Center after all.

    • better yet (Score:4, Interesting)

      by tjw ( 27390 ) on Sunday June 05, 2005 @08:16PM (#12731916) Homepage
      > Put the base in the ocean, and stick a carrier task force there to protect it.

      Better yet, put it on Nauru.
      http://www.cia.gov/cia/publications/factbook/geos/ nr.html [cia.gov]

      With the phosphates gone, the international money laundering (er banking) industry dismantled, and nothing else on the horizon, this could be just what this island nation needs.

      Finally something that severe isolation is good for.

  • I find this technology very intriguing. But it took me a long time to realise that they are serious. First time I heard about this I had to check if it was April first.

    Anyway, the most interesting thing I heard in this interview was that they said that if you let the elevator go up really far, close to the counter weight, and let go of an object there, it would fly faster than with conventional rockets because of the centrifugal motion.

    So that could be used to fling stuff from earth really fast. And since
    • I find this technology very intriguing. But it took me a long time to realise that they are serious. First time I heard about this I had to check if it was April first.

      They're serious, and poised to succeed just as well as the dozens of people and companies who have been studying the problem for decades.

      The space elevator won't happen in your lifetime. Just like the permanent moon base, the SDI and hundreds of such grandiose and vaporous projects. The only one I've seen completed that I didn't think woul
      • The space elevator won't happen in your lifetime. Just like the permanent moon base, the SDI and hundreds of such grandiose and vaporous projects.

        The moon base, SDI, and all the other grandiose projects would all be made possible by the space elevator. The reason they haven't happened so far is because lifting large amounts of mass into orbit is just too expensive with rockets. Once you can lift entire buildings into orbit on a weekly basis, a moon base is almost trivial.

        As for the space elevator n

    • Re:Going to the moon (Score:3, Interesting)

      by HiThere ( 15173 ) *
      Remember: Net momentum change up and down must equalize, or the weight changes it's orbit. And you need a heavy weight to provide enough ballast.

      That said, there are larger problems, and this is probably an overly ambitious approach. I think that it would be better to start with pinwheels rather than a space elevator. You get about half the advantages, at a considerably reduced construction cost. And one pinwheel serves many locations on the earth. (You may well need to wait several hours for one to c

  • *NIX and no Real (Score:2, Informative)

    by zp ( 68133 )
    % mplayer -ao pcm:file=20050603_totn_03.wav 'rtsp://real.npr.na-central.speedera.net:80/real.n pr.na-central/totn/20050603_totn_03.rm'

    Should work if one has mplayer but does not have realplayer.

  • Interesting interview (Score:3, Informative)

    by drgath159 ( 821707 ) on Sunday June 05, 2005 @06:20PM (#12731277)
    Covered a lot of the questions that have popped into my head while reading the previous 947 Slashdot/Space-elevator articles.

    Highlights
    - Location? Straight south of California near the equator.
    - Timeframe? 15+ years
    - What if an airliner flew into it? Pretty much screwed. But the location is 400 miles from any air route so shouldn't be a problem.
    - How long would it take to get up? A few hours.
    - Wouldn't it be a huge lightning rod? Yeah, but that area of the world does not have lightning, so shouldn't be a problem.
    - Wouldn't the car that goes up the cable just pull it down and not crawl up it? Yes, but the car is only a few tons and the weight of the cable and weight on the other end was something like a couple thousand tons. So shouldn't be a problem.

    There are a lot of "shouldn't be a problem"'s in there that one of them will be a problem. Exciting technology though.

    • Re:Interesting interview (Score:5, Interesting)

      by MrResistor ( 120588 ) <peterahoff.gmail@com> on Sunday June 05, 2005 @07:38PM (#12731709) Homepage
      There is no such thing as a place in the world that doesn't have lightning. That's just stupid.

      Besides, there doesn't need to be lighting for electricity to be an issue. You can generate electricity by moving a conductor through a magnetic field. I would think 62k miles of carbon nanotube ribbon running through the magnetic field of the earth would make a pretty good generator.

      IIRC, they already have to deal with this when tethering satalites to the space shuttle. I remember hearing that every material they've tried has some length at which it generates enough power to burn itself up (though that length might be several miles).

      • There is no such thing as a place in the world that doesn't have lightning. That's just stupid

        What's stupid is making a blind assertion like the above, without any facts or knowledge to back it up. Apparently there are places without lightning, and this is one of them. If you have some knowledge to the contrary, let's hear it.

        You can generate electricity by moving a conductor through a magnetic field. I would think 62k miles of carbon nanotube ribbon running through the magnetic field of the earth

  • Have you ever run up a flight or two of stairs? Just getting going isn't good enough. You need a sustained input of energy to keep going.

    This elevator will propel its payload straight up at 200 mile/h, using solar power? Those are mighty powerful solar panels.

    In a nutshell, you have to supply escape-velocity energy to any mass you drag up the thing. No two ways about it.

    • Re:No free lunch (Score:3, Informative)

      by yotto ( 590067 )
      Sorry, but you're wrong.

      The current solution to the problem you outlined is to shoot the thing with a laser (a big frickin' laser) on the ground. Keep the laser trained on the elevator car, and on the car convert that light to the electricity you need to crawl up the line.

      I wouldn't be surprised if some day some smart engineer figures out a way to use the potential energy of a down-moving car to supply some of the energy to an up-moving car (Not all, of course, gotta pay mister Entropy).
      • Where does the power from your "big frickin' laser" come from? I don't call 200 mile/h "crawling up the line."
        • Where does the power from your "big frickin' laser" come from?


          From a power generating facility. Nuclear, coal, oil, solar, wind, natural gas, whatever type you care to use.

    • What I wonder is why they don't take large pieces of space junk and just send those down toward the ground to counterweight the lifting of the mass?
    • in which case all you have to overcome is friction. (a la Traction Elevators, Paternosters, Funicular Railways, etc.)

  • skiers know... (Score:2, Interesting)

    by kencurry ( 471519 )
    What it's like to get stuck mid-air on a long lift.

    God help you if the elevator goes on the fritz in the midst of your ride!

  • What about space debris? (Score:3, Interesting)

    by d474 ( 695126 ) on Sunday June 05, 2005 @06:31PM (#12731342)
    What kind of damage can the ribbon sustain if a small meteorite or space junk impact it? No big deal or total failure?
    • It's not completely clear. However the potential tensile energy of the cable under normal loading is entirely comparable to a high explosive per kg of cable.

      Basically, it has been suggested that if the cable breaks a 'spray' of fragments will be thrown up and down the cable, possibly causing further damage.

      Freeman Dyson is on record as saying that he doesn't think it will work for essentially this reason "but he's willing to be persuaded". This from a man who once wanted to sit on a few thousand explod

    • What kind of damage can the ribbon sustain if a small meteorite or space junk impact it? No big deal or total failure?

      It really depends on the size of the object hitting the ribbon. Whatever hits the ribbon will likely be going fast enough to drill right through it, leaving a hole where it hit in the shape of its cross-section (think Wile E. Coyote). That's one of the reasons why they propose to use a wide flat ribbon instead of a cable -- if a small object hits it, it might leave a hole and weaken the

  • Really informative video (Score:3, Interesting)

    by drgath159 ( 821707 ) on Sunday June 05, 2005 @06:31PM (#12731353)
    http://www.isr.us/video/SE-INTRO_Final-1stream-384 .wmv [www.isr.us]

    Covers the basics of the elevator, what it looks like, how it works, etc...

    The question of how this thing is powered never popped into my head before, but the video shows that they will use a lazer shot from the base station. Crazy stuff.
  • I could probably use that to find myself a life...

  • NPR talks skyhooks. (Score:3, Interesting)

    by lgroner ( 448176 ) on Sunday June 05, 2005 @06:52PM (#12731467)
    One weakness of the plan, as I see it, is the all or nothing nature of the plan. A less risky plan that could be a stepping stone to a space elevator is to start with a much smaller rotating tether in orbit.

    Imagine a thousand mile long tether in orbit with its center of gravity 600 above the earths surface. In addition to orbiting the earth The tether would rotate about its center of gravity at a rotation speed such that its speed relative to the earths surface at its ends closent approch would be zero.

    A rocket would have to ascend to 100 miles up and rondezvous with a a tether end that, for the moment, is stationary. It would remain atteached to the tether while the tether rotated 180 degrees about its center of gravity. At tht point the rocket would be 1100 miles above the earth and traveling at about twice orbital velocity. If the rocket detatched at this point would would be well above escape velocity.

    Longer tethers would reduce G forces and avoid the need for the first 100 mile step. The ultime version of the tether would have a CG in geosynchronous orbit and aon end on the ground.
  • One of the issues that I keep reading about a space elevator is how the cart will be provided energy to move up. Well, how about a space goldola instead of a space elevator. Why not have the orbiting mass have a pulley connected to two pulleys on the ground with each at a seperate ground (or ocean) station seperated by several kilometers. The accute triangle that this system would create would allow a space gondola to ride up a moving cable without getting entangled. The cable, of course, being moved by th

  • Solution to problems: space fountain (Score:3, Interesting)

    by Oniros ( 53181 ) on Sunday June 05, 2005 @07:27PM (#12731639)
    I thought space elevators with cables were out (due to the tensil strength the cable should have) and space fountain were in (since easier to build, not just buildable on the equator, etc.)

    http://en.wikipedia.org/wiki/Space_fountain [wikipedia.org]
  • Why build a skyhook? You know Dash Rendar's just going to fly by and blow it up...
  • I always love it in SciFi novels when their space elevators snap because of a terrorist attack or one failed component in an insanely long chain of parts.

    Fantastic.
  • Seeing it hasn't been brought up yet, no material strong enough to build the elevator yet exists. It is not yet clear whether it is even possible to do so. Carbon nanotubes may be strong enough, but nobody has yet been able to assemble them together into a "ribbon" of the strength required yet.

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