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."

Comments

Skyhooks?

[imroy]

Does the audio program mention the word "skyhook"?
Why bring up the Aussie 70's supergroup?

wrong concerns

[cryptoz]

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!

Re:wrong concerns

[bobetov]

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

[GameMaster]

The planes used in the 9/11 attack were 4 planes flying in an airspace occupied by so many other commercial aircraft that the FAA has a hard time tracking them all. The number of flights flying around the Northeastern United States is insane. Also, there was no reason for the military to think those planes were necessarily going to be used as weapons so they probably didn't think there was a need to break the regulations that stop them from going too fast over populated areas.

This proposed space elevator is supposedly around 400 miles from any commercial air lanes. Long before a plane actually enters a no-fly zone it can be intercepted and questioned as to why it's even getting close to the elevator. Also, if an aircraft carrier were stationed close to the elevator they would:

a) have nothing better to do than watch for planes getting close
b) they would always have it in the back of their minds that a plane could be used to attack the ribbon
c) they would have no other distractions in the airspace for hundreds of miles

There is no reason to think that, under these circumstances, highly trained fighter pilots flying heavily armed modern fighter craft would be unable to shoot down any civilian aircraft that strayed too close and couldn't be convinced to peacefully leave. For that matter, there is no reason to think, now that we have seen them used as weapons, that the US Airforce couldn't do the same thing in the continental US should another situation like 9/11 occur again.

-GameMaster

The next x-prize

[maelstrom]

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.

Re:The next x-prize

[drwho]

Any such competition would likely come with "strings attached". ;)

Answer

[Rosco P. Coltrane]

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

Re:Cripes

[Rei]

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.

I just have to ask...

[NotQuiteReal]

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?

Muzak

[Anonymous Coward]

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!

kiddies beware...

[moviepig.com]

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

[Profane MuthaFucka]

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.

Interesting interview

[drgath159]

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

[MrResistor]

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).

Really informative video

[drgath159]

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.

NPR talks skyhooks.

[lgroner]

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.

better yet

[tjw]

> 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

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.

My standard space elevator comment...

[Goonie]

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.