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NPR Talks Skyhooks
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."
Does the audio program mention the word "skyhook"?
Why bring up the Aussie 70's supergroup?
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!
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.
The more you know, the less you understand.
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
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
I was thinking the same thing. It's way overhyped. Although, the concerns cited in the summary aren't that major.
Commercial airliners will never get close to it; that's what no fly zones are for. Even if an airplane crashed into it, one solution successfully deals with both airline impacts and lightning: "maypoling" the skyhook as it nears the ground (i.e., splitting it into several cables, of which most, but not all, are needed for stability/strength.) As for lightning itself, most types of CNTs would be the "path of most resistance", barring heavy condensation on the cable. Plus, some sites in the world have very little lightning.
We should start dealing in those black-market beagles.
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?
This issue is a bit more complicated than you think.
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!
*Don't space elevators have to be built along the equator?
I thought this as well, but no, they don't. A rough diagram of a space elevator would be:
O--------
Where the "O" is the Earth. Imagine, right before "tying down" the base of your elevator, you drag i "up" a few dozen degrees to New York. The farther North you go, the more of an angle it will have, but it's not unstable so long as it's anchored.
The first thousand miles of the climb would be like a very steep gondola ride.
Pulp Audio Weekly - Geek News and Reviews
It isn't overhyped until there are competing groups actually building one. Furthermore, what is "overhyped on slashdot" is rarely even in the public consciousness. Live with it, love it, until it spills into the public imagination and gets warped into an evil, multi-national corporation's wet dream. THEN complain.
I agree that most of the technical objections are not-too-hard-to-overcome engineering challenges, not showstoppers. If you're reading this and think you have a fatal flaw to the whole concept, and haven't spent months on it doing some calculations and reading papers, I'll take the opportunity to laugh at your idea now.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
I guess the old prank of jumping onto a crowded car and pushing all the buttons would be a no-no...
Seeing bad movies only encourages them. Watch responsibly
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.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
% 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.
ZP
We only can learn from our mistakes.
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.
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!
sigs are for losers (except to point out that sigs are for losers)
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).
Pulp Audio Weekly - Geek News and Reviews
What kind of damage can the ribbon sustain if a small meteorite or space junk impact it? No big deal or total failure?
Authority questions you. Return the favor.
http://www.isr.us/video/SE-INTRO_Final-1stream-384 .wmv
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...
I don't think the space elevator is quite as ambitious as the tower of Babble, After all the space elevator only goes to orbit, not to Heaven.
Yes. I'm not laughing. That's an informed opinion based on knowing something about material science.
Progress has been fast with CNT materials. The promise (which is a promise not a certainty) is that we'll know if we can make a strong enough material in the next five years based on CNT technology. Investing in this sort of research is a good idea (and we nearly hired someone this year who worked in the area).
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
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.
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 come by unless more than one is built...but that's not a real problem.)
A pinwheel is several cables attached to a weight and rotating. The arms reach down into the atmosphere to pick up or release cargo. You fly up to reach them in an airplane, and the cargo is picked up or released. You want this to be high enough to have minimal friction, and you want the speed of rotation to be slow enough to give plenty of time for the transfer.
Again, momentuum change needs to average out to zero. But the pinwheel can loft you to a higher orbit, and catch you on the way back down (helping to equalize momentuum).
Pinwheels could actually be even more flexible than space elevators, as they could act as momentuum transfer devices in a way similar to slingshot orbits, but you could position them for your convenience. (That's long term, however, but they don't always need to be in orbit around a planet, the also work in solar orbit.
And pinwheels don't require the super-strong cables that space elevators require (though it would certainly make them more attractive).
I think we've pushed this "anyone can grow up to be president" thing too far.
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
Why build a skyhook? You know Dash Rendar's just going to fly by and blow it up...
#define QUESTION ((bb) || !(bb))
You confuse maypole and hoytether. A maypole is a radial structure where the cables merge at a single point and diverge thereafter. A hoytether is a regularly interconnected series of cables. Maypoles lose equal strength with every hit. Hoytethers lose less and less strength with each successive random hit. The downside to a hoytether is that your mass requirements grow greater and greater the further apart your base cables are. It's not realistic to make your whole skyhook have its component cables be far enough apart that its earth intersection would be safe from lightning/aircraft impacts.
We should start dealing in those black-market beagles.
> Put the base in the ocean, and stick a carrier task force there to protect it.
/ nr.html
Better yet, put it on Nauru.
http://www.cia.gov/cia/publications/factbook/geos
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.
XJS*C4JDBQADN1.NSBN3*2IDNEN*GTUBE-STANDARD-ANTI-U
There was a real system called "Skyhook" developed by the military. Basically it was a one man recovery system intended for use by spies, downed pilots, etc. Someone on the ground let up a balloon with a cable attached and harnessed themself to the end. A plane with a special "Y" shaped "cable catcher" on the front would then fly into the cable and eventually the "recoveree" would be winched on board. Apparently they did get it working http://www.cia.gov/csi/studies/95unclass/Leary.htm l
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.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
At the time, it was better known as Babel. It wasn't named Babble until the people could no longer understand each other.
Later of course, Babel and Mabel got together and had lots of Baby Bels. The runt of the family was nicknamed Deci Bel.
Time flies like an arrow. Fruit flies like a banana.
Like building a tower of babel is hard! I've built serveral, the secret is realising that
"ooo heavean is a place on earth"
I thankyou.
In the not too distant future, next Sunday A.D.