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Highlift Systems' Space Elevator In The News Again
Kris_J writes "Highlift Systems may have found a second location for the anchor of their space elevator -- Perth, Western Australia. Apparently we have the calm waters and international airport that it needs, amongst other things. Slashdot has covered this company's efforts before: Oct 9, 2002 and, earlier, August 13, 2002, but it's worth discussing again since '[recent funding] has been given momentum by the Columbia shuttle disaster.'"
Willy Wonka would love this!
http://www.howstuffworks.com/space-elevator.htm
Centrifugal force. I have the .pdf file, the examination on the plausability of this working. The cable would be 60,000 miles long. At this length the force of the Earth spinning would hold the end of the cable outwards in a straight line.
The first cable would be 1 micron thick, and taper from 5cm wide at Earth to 11.5cm in space. This would be added to each climb. By the 107th addition it would be capable of holding a climber of 22tons with a 14 ton payload.
Of course it would be made of Carbon nanotubes (the only thing that could possibly be strong enough and light enough).
Now I'm not saying I believe it can or will be done. I'm only quoting Bradley C. Edward's paper.
See the world is round and Australia is at the bottom of it. So by putting it in Australia it can just kinda dangle off of earth into space (being that Australia is down under and all).
I hope the clears it all up (or down as the case may be) for you.
man
No manual entry for
"But with a start-up cost of $17 billion, the idea needs strong US and Australian government support."
Lyle Lanley: Well, sir, there's nothing on earth
Like a genuine,
Bona fide,
Electrified,
Six-car
Monorail!
What'd I say?
Ned Flanders: Monorail!
Lyle Lanley: What's it called?
Patty+Selma: Monorail!
Lyle Lanley: That's right! Monorail!
It's not a stupid question. Get a ball on a string and whirl it round. The ball doesn't lag does it? The outward pull of the ball keeps the string taut. The exact same effect will be used by the elevator. Locally, in the atmosphere, the cable will be stationary, so it will have to resist wind loads, but they have worked those out. There is also some drag due to space debris and solar wind, but again they have accounted or that.
Good article, nice website, fantastic project. As Arthur C Clarke said (I think, loosely), we'll be using a space elevator about twenty years after everyone stops laughing at the idea.
I think they will have to choose the music for this elevator VERY carefully. I mean, how long will it take to get up there? You don't want people to go insane and stuff.
:)
Although, it would make for a REALLY good tv-movie.
First of all, theres no way that the structure could be supported solely from the ground, the bottom is anchored, but thats not why its rotates with the earth. Rather, the top is anchored to some heavy object (read asteroid or the like) that is (somehow) placed into a geosync orbit. The structure merely provides a way to efficiently travel from earth to the other object (as you have a solid medium to push against and facilitate the change in grav. potential).
P.S. Yes, technically the orbit of the top of the elevator/upper anchor is not geosync, but rather slightly above geosync to allow for the center of mass of the contraption to be geosync in its orbit, (and the bottom anchor then serves to maintain the proper orientation).
**AA: a bunch of mindless jerks who'll be the first against the wall when the revolution comes
What happened to Sri Lanka? I thought the goal was to get as close to the equator as practical.
No, Sri Lanka was to get it as close to Arthur C. Clarke as possible.
Eve Fairbanks says I drive a hybrid!LOL
There is NO SUCH THING as "centrifugal force". "Centrifugal force" is the effect of tension in a cable against the center of rotation caused by CENTRIPETAL force accelerating the swung object towards the center.
It's like this...a car pulls a trailer. The car is pulling the trailer! There is a force acting backwards on the trailer hitch on the car, but it is actually the car pulling the trailer, not the other way around. The anchor is not pulled by the swung object, the anchor PULLS the swung object.
If the string is cut, the object does not accelerate away from the anchor because of some centrifugal force; the object will STOP accelerating and continue along in a straight tangential line.
Centripetal force is real, centrifugal force is apparent.
For technical reasons this only works when the bottom of the elevator ribbon is suspended a few feet about a small wicker basket; however, the idea is sound.
This also alludes to the second problem in keeping the elevator vertical - once the material strength issues are solved, you still need to find someone who can play the flute indefinitely without stopping. The Perth placement is partly designed to take advantage of the circular breathing techniques developed and perfected by the local didgeridoo players.
The above post makes an excellent point, there is currently no material that can sustain the enormous stress that would be required to construct a space elevator.
While there is no current material that yields the necessary strength/mass required in order to built a space elevator, realistic possibilities are on the horizon. Quite simply, with the advent of nanotechnology, we are nearing the technological feasibility of creating a material composed of intertwined nanotubes. This is theoretically the strongest material that can ever be created. Carbon-Carbon bonds are extremely strong and would be extremely densely packed in a nanotube pole. It would be an order of magnitude stronger than steel, as well as significantly lighter.
While nanotubes can already be readily produced (Dr. Smalley of buckyball fame operates a production facility), strong nanotubes rods have yet to be produced. This is due to a variety of technical hurdles that must still be overcome. Perhaps the foremost obstacle is getting the produced nanotubes to lie parallel to each other. The current production method has the nanotubes forming from a catalyst and then becoming intertwined in a jumbled mess. When tension is applies to the mesh, the rope breaks not within the nanotubes (which would require a great deal of energy), but between the nanotubes, unraveling them from each other. Attempts to get the nanotubes to align properly have failed. Nanotubes are not an easy molecule to work with. They have extremely strong cohesion forces and are very difficult to pull apart from one another. The obvious approach of functionalizing each nanotube in order to orient it correctly doesn't work as doing so causes the nanotube to lose much of its mechanical and electrical promising properties.
In addition, when nanotubes are put under extreme mechanical stress, the bonds within the nanotube shift. For example, I've seen simulations where the bonds separating two polygons disappears, creating what appears to be a bonding who in the nanotube. The hole then resonates through the nanotube causing significant weakening in the structure.
At a talk I attended, the most promising idea I heard discussed was a steel/nanotube alloy. The nanotubes would run vertically through the steel, reinforcing the structure in the same way steel rods are often used to reinforce concrete. This would alleviate the risk of the nanotubes becoming unraveled intermolecular while at the same time using their large intermolecular strength to reinforce the structure.
Of course, without any physical models, this is mere speculation. However, it suffices to say that a there are real possibilities of breakthroughs that would allow for the construction of such a space elevator.
I don't get it either. But as some of the other posts have mentioned, it wouldn't be orbiting, it would be getting 'swung' around by the earth.
Would a physicist please correct the following?!
I picture a tether at the equator going out at 90 degrees. If you move down to Perth, the tether will still go out at 90 degrees to the axis of rotation wouldn't it? That is, it would go out parallel to the tether at the equator. See diagram.
X
XX
XXX
XXXX
XXXX---------O equator
XXX
XX---------O perth
X
So, does that mean that it wouldn't be vertical at perth but would go out at an apparent 31 degrees?
Also, does that mean that the thing actually goes over all of the airspace between 31 degrees and just south of the equator? That is, because of the angle, would it actually go over, say, Indonesia's airspace.
Parts of Indonesia are nearly 10 degrees south. Does a line drawn vertically from Indonesia intersect with the ribbon?
I'm appalled at the lack of imagination shown by most of these posts.
First off if you read the PDF (15M) report to Nasa prepared by Bradley C. Edwards to satisfy the requirements of his $500 000 grant you will readily see that this is totally feasible.
Next check out the website - where they are calling for people to express interest in working on this project. They expect to be hiring in the next year or so. You'll also see that serious people are taking this seriously. Do you want a job?
Next understand that $17B is not very much money. Considering that BP just spent $6.7B on a oil company in Russia and has plans for more purchases.
I meantion BP because they have a plan to move beyond oil.... BP Solar is BP's attempt to become a broader energy company (check out their new sun logo) instead of an oil company. The High Lift systems news page says: -
BP Solar - a subsidiary of British Petroleum, currently doing $300M in annual sales. Our discussions have focused on BP's interest in using the SE for deployment of a solar energy satellite. Several items that came up included possible collaborative efforts, the performance of our system and the possibility of BP using our system. They are considering writing a letter of endorsement
If BP with the cash they have can throw $6.75 B at Russia they could, over 5 years, finance a large share of the Space Elevator. Who needs the Government? In fact Nasa would make sure it costs more to build than it should. Nasa is a bureaucracy, not a business, and is ill-suited to the sort of cost control required of economically viable business decision. Only communists would argue that a Space Elevator should be built and controlled by government.
What would BP Solar do? Build Power Sats....
These are High Lift's vision for the main use for the Space Elevator. Imagine a fleet of these beaming power to anywhere on earth. Every country on the planet could get cheap electricity without the huge national grid infrastructure required now. Without the huge investments in time and resources to build power stations - and without the fossil fuel use.
Use your imagination.
These ideas have been the subject of SF for decades - but the Space Elevator is now possible due to those nifty Carbon Nano-tubes.
When your imagination focussed by the reality of this thing actually being built in the near term (5 years) everything changes - and it'll change for us not our children. It'll change our careers.
Imagine this - an electric airplane that is powered by a Powersat beaming microwaves to it. No fuel to carry, super efficient travel - and at what speeds?
These guys are planning for the Space Elevator to be operational SOON - they have realistic timelines.
What I want to see here is some discussion of the uses that could realistically be made of a space elevator. We're the generation that will built it, use it and be changed by it. I like the parallel to be made with electricity, or flight, or the steam engine - in the early stages everyone probably dismissed it - and the world changed despite them.
What would you realistically (with a nod towards economic viability) do with the low launch costs they're projecting - $10/LB...
Ideas anyone?