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."
"what happens if the cable is cut four feet above the ground? does it come crashing down to earth? does it fly off into space?"
It should fly off into space. The way that it works is that the ribbon is counterweighted at the far end in order to provide centrifugal force that overcomes earth's gravity. This makes the entire ribbon stable in an epic zero-sum game.
Now, what you should REALLY worry about is what happens if an asteriod knocks some of the counterweights off. Of course, the chance of that happening are extremely slim.
As cool as this sounds, I can't help but wonder: What would happen if 62,000 miles of cable fell to earth from space?
Someday. Just wish I was born after warp drive (or whatever it will be called) was invented. Or had a 500 year lifespan :) Still lots of exciting space science going on every day!
"Too Soon From The Caves, Too Far From The Stars" Title of a Ray Bradbury collection of essays.
It sounds elegent, but it also sounds like something out of an Arthur C. Clarke novel.
I grew older in Fairmont from 1950 to 1959 when I escaped; the only thing notable about that place was crooked politicians and hotdog joints.
If the tidal force doesn't destroy it, then a few space rocks definently will.
It moves into space; the big problem is if the elevator parts above the midpoint... It fall to earth at hypersonic speeds wrapping around the planet!
Assuming of course it doesn't burn up.
Sorry, I just had to say that again, especially the "escaped" part.
They've cleaned up the hot dog joints.
So, aside from working on satellites and throwing waater balloons on those looking up, what else can it be used for??
Got link? Google is coming up with not much relating to your assertion.
Bill Gates could do this.
The cost of carbon nanotubes has to come way down and AFAIK I don't think they've figured out a way to produce long strands of them yet, which will be needed. Otherwise . . . THE SOONER WE GET STARTED, THE BETTER!
I did read an article a while back that claimed a space elevator would be obsolete before it could be completed. But it seemed like that author was making a lot of iffy assumptions about how quickly alternative propulsion research would progress.
So let's do it!
"The horizontal velocity of that cab -- at geo-sync altitude -- will be staggering, and even though it's "undetectable" at altitude, when you lower the cab, it will be like trying to contain a cannonball with a spiderweb."
Actually... um...
Only delta-v over time matters - that is, acceleration. If you raise or lower the cab slowly enough, the change in velocity will not be big enough to cause problems.
First, you'd need a device strong enough to cut it.
Only as far as an Otis elevator is a perpetual motion scam. Balance the weights and the ride is free.
"Two years" translates to 10 years, at least -- he's only talking about the basic materials research, and it would probably take more than two years. After that, he's still got to find a way to create, not to mention test, 20,000 flawless miles of this stuff.
And his $10 billion is also undoubtedly way off -- probably by at least a factor of 10. It would cost a lot more than that just for the rockets to launch the material and dispenser into space (you have to drop it down from GEO; you can't put it up from the ground.)
Not to mention R&D on the enabling technology -- cable manufacturing, the dispenser bus, ground receivers, "elevator" stabilization technology, shielding, repair vehicles, figuring out how to repair the cable when it's under tension, and whatever other stuff needed to create and deploy a long, continuous cable, and so on.
It's a great idea, but there's a lot of stuff that needs to happen before this can be made to work. This guy's shading the truth, which is too bad.
"Someday. Just wish I was born after warp drive (or whatever it will be called) was invented. Or had a 500 year lifespan :) Still lots of exciting space science going on every day!"
I quit smoking and drinking. When i questioned my self as to why, the only answer i could come up with was "because i want to see what happens next". I'm only 40 years old but Ive seen some amazing things in my life.
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