Posted on 06/25/2004 2:21:35 PM PDT by Junior
WASHINGTON - President Bush (news - web sites) wants to return to the moon and put a man on Mars. But scientist Bradley C. Edwards has an idea that's really out of this world: an elevator that climbs 62,000 miles into space.
Edwards thinks an initial version could be operating in 15 years, a year earlier than Bush's 2020 timetable for a return to the moon. He pegs the cost at $10 billion, a pittance compared with other space endeavors.
"It's not new physics — nothing new has to be discovered, nothing new has to be invented from scratch," he says. "If there are delays in budget or delays in whatever, it could stretch, but 15 years is a realistic estimate for when we could have one up."
Edwards is not just some guy with an idea. He's head of the space elevator project at the Institute for Scientific Research in Fairmont, W.Va. NASA (news - web sites) already has given it more than $500,000 to study the idea, and Congress has earmarked $2.5 million more.
"A lot of people at NASA are excited about the idea," said Robert Casanova, director of the NASA Institute of Advanced Concepts in Atlanta.
Edwards believes a space elevator offers a cheaper, safer form of space travel that eventually could be used to carry explorers to the planets.
Edwards' elevator would climb on a cable made of nanotubes — tiny bundles of carbon atoms many times stronger than steel. The cable would be about three feet wide and thinner than a piece of paper, but capable of supporting a payload up to 13 tons.
The cable would be attached to a platform on the equator, off the Pacific coast of South America where winds are calm, weather is good and commercial airplane flights are few. The platform would be mobile so the cable could be moved to get out of the path of orbiting satellites.
David Brin, a science-fiction writer who formerly taught physics at San Diego State University, believes the concept is solid but doubts such an elevator could be operating by 2019.
"I have no doubt that our great-grandchildren will routinely use space elevators," he said. "But it will take another generation to gather the technologies needed."
Edwards' institute is holding a third annual conference on space elevators in Washington starting Monday. A keynote speaker at the three-day meeting will be John Mankins, NASA's manager of human and robotics technology. Organizers say it will discuss technical challenges and solutions and the economic feasibility of the elevator proposal.
The space elevator is not a new idea. A Russian scientist, Konstantin Tsiolkovsky, envisioned it a century ago. And Arthur C. Clarke's novel "The Foundations of Paradise," published in 1979, talks of a space elevator 24,000 miles high, and permanent colonies on the moon, Mercury and Mars.
The difference now, Edwards said, is "we have a material that we can use to actually build it."
He envisions launching sections of cable into space on rockets. A "climber" — his version of an elevator car — would then be attached to the cable and used to add more lengths of cable until eventually it stretches down to the Earth. A counterweight would be attached to the end in space.
Edwards likens the design to "spinning a ball on a string around your head." The string is the cable and the ball on the end is a counterweight. The Earth's rotation would keep the cable taut.
The elevator would be powered by photo cells that convert light into electricity. A laser attached to the platform could be aimed at the elevator to deliver the light, Edwards said.
Edwards said he probably needs about two more years of development on the carbon nanotubes to obtain the strength needed. After that, he believes work on the project can begin.
"The major obstacle is probably just politics or funding and those two are the same thing," he said. "The technical, I don't think that's really an issue anymore."
ah, the infamous "sky hook" makes a comeback wearing a bit
of a disguise.
I hadn't seen that, thanks for the link. Yup, welfare -- and welfare mentality -- both on the open-mouthed baby-bird going cheep-cheeep-feeeeeed-me level, and, on the scumbag effendi making "good money" dropping my money into that bottomless maw.
Good point, too, further down in the article: "In general, I don't know when inspiration will pop up." Yup, it sucks. I try to jot ideas down (I've got nearly a book's worth of ideas that I pick from) while the fire's still in my belly, so to speak. (I'm attempting to make the break from technical writing to writing SF. With any luck I'll find out some time this year whether I can make it or not. I do have a "my next book" contract option, but that particular publisher doesn't do SF, so it'll be interesting seeing how they reject it. My hope is that they don't take my sweet time "deciding" whether to exercise their option. Argh...)
People usually snap to their senses when the threat looms large enough. The key will be whether they snap to their senses before it's too late or if they will wait until nothing can be done about it before noticing the problem.
I don't know that I'm quite that optimistic. Rather than, "People usually snap to their senses when the threat looms large enough," I see it as, "When people snap to their senses, it's when the threat looms large enough."
I'm thinking "The Postman" may end up being a "wouldn't it have been nice if things were only that bad" scenario.
Hmmm, I never knew that. I had read that Kubrick was still editing 2001 up until the last minute. Perhaps the extra time did some good. Also, Kubrick had to change a line in Dr. Strangelove because of JFK's assassination. Speaking of Kubrick and historical events. Did you ever see the article drawing the similarities between the Excavation pit at the WTC with the excavation pit at TMA1?
Yes. But not at "tens of thousands of miles per hour". My calculations show geosynchronous orbit to be 6900 miles per hour, which isn't even a single "ten of thousands".
Well, that sideways velocity has to go somewhere -- and the only place to put it is to sink it into the "elevator" ribbon.
Right again. However, that's not the problem you make it out to be. You're right about the basic physics, but wrong in your intuition about how big an effect that will have. Try running the numbers before you opine on it.
Someone suggested that if you move it slow enough, it won't matter.
And they are correct.
I got a chuckle out of that, because all the pictures I've seen of proposed "elevators" show things moving pretty darned fast. The NASA page linked above in this thread shows what looks like a rocket -- a very streamlined "shuttle"-looking cab. I can't picture that thang slowly inching along the ribbon.
"Fast" and "slow" are relative. At 1000mph vertical velocity, that's "pretty darned fast", but it's slow enough that it'd take over 22 hours to make a one-way trip -- and that allows 22 hours for the horizontal velocity to be transfered to the cable from the car (or vice versa), which is a very slow, gentle transfer of energy.
A piece of lead weighing only a few grains will wreak havoc if it hits something made of meat (or wood, or metal, or...) at a few thousand feet per second.
If it hits it and has to transfer all that energy *all at once*, yes. That's not the case for the space elevator. Likewise, the Space Shuttle would vaporise if it had to go from orbital velocity to a landing instantaneously, but since it actual deorbits and slows down for a landing over most of an hour, no problem.
Visualize the forces involved in sinking the energy carried in a mass of a few tons, traveling at miles per second.
You mean like the Space Shuttle? Gradually enough, no problem.
Forget I said anything, OK?
If you insist.
Help me here -- what's the advantage to using "software programming at a distance" for the purpose of designing a telescope on the moon?
I mean, why not simply design it here, and then -- *blurp* -- a few seconds later, there it is, the data arrives on the moon?
Now, I realize that by asking you this question, I run the risk of you frothing into another fit, insulting me for my endless stupidity, cupidity, straw-horsery, and inability to grasp the Deeper Things that you've read dozens of articles about, but hey, here I go anyway. :)
That's a common misconception. It can do no such thing, however. What quantum entanglement produces is long distance correlations, and as statisticians say, correlation is not causality.
It doesn't transmit information. Correlation at the far end is information. The change of spin at the source particle could represent a binary 1 or 0 at the distant particle.
Leinster's landing grid! :)
Yikes.......interestinng idea, but how long would it take to get up there.....days?
Actually, all the satellites (and debris) in the Clarke belt are "motionless" with respect to each other, and thus won't "cross paths". The whole *point* of that orbit is that things "don't move", they stay in the same fixed spot over the Earth.
That's similar to how it could be done (and if I recall correctly that is the intention) with building the space elevator ribbon. Once the first ribbon is up they have a minimal strength elevator. Then a small, light weight elevator would be lowered down to lash together the individual strands. Each time making the ribbon X amount stronger.
"Fish-tape to the stars!" :)
(Now where'd I leave that galactic stud-finder?)
"phrase of the day" winner right here
I am very familiar with the procedure, having participated. So, just what size rope do you recommend to attach to pull the rope in Normandy, France to the rope in New York City?
Either you're being facetious or you don't understand the similarity is not, nor was, meant to be exactly the same operation. Though similar enough to to be analogous.
Get over yourself, kid.
We had an FR discussion of the distinction between geostationary and geosynchronous a while back. Then we took that 2 week course in etiquette.
Um, how do you propose getting that remote particle to its location across that "vast distance"?
See Wired April 2003 for more detail
http://www.wired.com/wired/archive/11.04/nanotech.html
See Wired 02:00 AM Feb. 04, 2003 for more detail
http://www.wired.com/news/technology/0,1282,57536,00.html
See pic
http://www.wired.com/wired/archive/11.04/images/sp_nanotech_2.gif
I'd be a little surprised if JIMO actually 'got off the ground,' as the saying goes. I have heard, though haven't been able to confirm, that JIMO is intending to use an actual reactor, which strikes me as trouble, both technically and politically. As you're no doubt aware, most previous heritage nuclear-powered spacecraft use radio-thermal generators (RTGs) - no moving parts, and sub-critical radioactive elements. A full on reactor would be trouble politically (for the record, I think it'd be cool, but given the current political environment, I'm pessimistic), but also for a couple of other reasons. One of the interesting problems for the Europa Orbiter (since cancelled) a few years ago was that it was necessary to demonstrate that the RTG (or individual elements of the RTG) would not penetrate the surface of Europa in the case of spacecraft impact (to reduce the chance for biological contamination). I suspect that that would be much harder to demonstrate for a real reactor. Plus, the expense of the mission is a bit high, given that your operational spacecraft life at Europa's orbit 'round Jupiter is measured in weeks if you're optimistic... Not insurmountable, but difficult and expensive.
-SV
Actually, Geo satellites "like" to drift intrack into known gravity wells.
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