Posted on 09/28/2005 1:16:19 PM PDT by saganite
Space may still be the final frontier, but getting there could soon be almost as simple as stepping into the office lift at the start of the day.
The race is on to build the first "space elevator' - long dismissed as science fiction - to carry people and materials into orbit along a cable thousands of miles long.
In a significant step, American aviation regulators have just given permission for the opening trials of a prototype, while a competition to be launched next month follows in the wake of the $10 million (£5.6 million) "X Prize'', which led to the first privately developed craft leaving the Earth's atmosphere, briefly, last year.
Supporters of the elevator concept promise a future in space that is both cheap and accessible, and contrast it to Nasa's announcement last week that it will be relying on 40-year-old technology from the Apollo programme for its $105 billion plan to return to the Moon by 2018. The companies behind the space elevator say they will be able to lift material into orbit for as little as $400 a pound, compared with $20,000 a pound using existing rockets.
That would open up the possibility of tourists visiting a sky hotel in stationary orbit 22,000 miles above the Earth, with a view previously enjoyed only by astronauts.
It would also allow for far cheaper travel to the Moon and other planets within the solar system, since most of the energy required by rockets is used simply to escape Earth's gravity.
Russian scientists first envisaged a fixed link to space, and the idea was popularised by the British sci-fi writer and vision-ary, Arthur C Clarke, in his 1978 novel, The Fountains of Paradise.
The theory behind the space elevator is deceptively simple. With a base station on Earth and an orbiting satellite, solar-powered "climbers'', each carrying up to 20 tons, would crawl up a single cable into space over several days. The cable would be held up by the rotation of a 600-ton satellite counter-weight, much like a heavy object at the end of a spinning rope.
Until recently, the concept seemed doomed by the technology available, not least finding a material strong enough to make such a long cable, able to withstand extreme temperatures.
Scientists now believe that a material known as carbon nanotubes could be bound together to make a ribbon, rather than a cable, three-feet across but just half the width of a pencil.
Nanotubes, which are microscopic cylinders of carbon, are currently being developed by a number of companies, including GE and IBM. In one experiment, a sheet of nanotubes one-thousandth the thickness of a human hair could support 50,000 times its own mass.
"Elevator 2010'', which is to be launched on October 21 in California, will offer an annual first prize of $50,000 for the best design for both a tether - or ribbon - and a lightweight climber. It is being run by the Spaceward Foundation, which promotes space exploration, and has the backing of Nasa, which has given $400,000 in prize money. At least 10 teams will take part in the first contest.
Brad Edwards, a board member of the foundation, says the initial development could be ready "in the next couple of years", with the elevator itself being built in another decade.
"We are talking about getting this up in about 15 years,'' Dr Edwards predicted.
A rival design is being produced in Seattle by the LiftPort Group, which is counting down to a first voyage into space on April 12, 2018. The Federal Aviation Authority last week cleared an experiment by LiftPort that would use a mile-long tether attached to a balloon, something the company calls: "A critical step.''
Fears that an aircraft would crash into the elevator ribbon is just one concern. Space debris and terrorism are others.
Developers propose a floating base station near the equator, more than 400 miles from the nearest flight path.
Should the 800-ton ribbon break, it would either fly into space or fall back to the ground in fragments that would, in theory, hit no harder than a sheet of paper
Space may still be the final frontier, but getting there could soon be almost as simple as stepping into the office lift at the start of the day.
The race is on to build the first "space elevator' - long dismissed as science fiction - to carry people and materials into orbit along a cable thousands of miles long.
In a significant step, American aviation regulators have just given permission for the opening trials of a prototype, while a competition to be launched next month follows in the wake of the $10 million (£5.6 million) "X Prize'', which led to the first privately developed craft leaving the Earth's atmosphere, briefly, last year.
Supporters of the elevator concept promise a future in space that is both cheap and accessible, and contrast it to Nasa's announcement last week that it will be relying on 40-year-old technology from the Apollo programme for its $105 billion plan to return to the Moon by 2018. The companies behind the space elevator say they will be able to lift material into orbit for as little as $400 a pound, compared with $20,000 a pound using existing rockets.
That would open up the possibility of tourists visiting a sky hotel in stationary orbit 22,000 miles above the Earth, with a view previously enjoyed only by astronauts.
It would also allow for far cheaper travel to the Moon and other planets within the solar system, since most of the energy required by rockets is used simply to escape Earth's gravity.
Russian scientists first envisaged a fixed link to space, and the idea was popularised by the British sci-fi writer and vision-ary, Arthur C Clarke, in his 1978 novel, The Fountains of Paradise.
The theory behind the space elevator is deceptively simple. With a base station on Earth and an orbiting satellite, solar-powered "climbers'', each carrying up to 20 tons, would crawl up a single cable into space over several days. The cable would be held up by the rotation of a 600-ton satellite counter-weight, much like a heavy object at the end of a spinning rope.
Until recently, the concept seemed doomed by the technology available, not least finding a material strong enough to make such a long cable, able to withstand extreme temperatures.
Scientists now believe that a material known as carbon nanotubes could be bound together to make a ribbon, rather than a cable, three-feet across but just half the width of a pencil.
Nanotubes, which are microscopic cylinders of carbon, are currently being developed by a number of companies, including GE and IBM. In one experiment, a sheet of nanotubes one-thousandth the thickness of a human hair could support 50,000 times its own mass.
"Elevator 2010'', which is to be launched on October 21 in California, will offer an annual first prize of $50,000 for the best design for both a tether - or ribbon - and a lightweight climber. It is being run by the Spaceward Foundation, which promotes space exploration, and has the backing of Nasa, which has given $400,000 in prize money. At least 10 teams will take part in the first contest.
Brad Edwards, a board member of the foundation, says the initial development could be ready "in the next couple of years", with the elevator itself being built in another decade.
"We are talking about getting this up in about 15 years,'' Dr Edwards predicted.
A rival design is being produced in Seattle by the LiftPort Group, which is counting down to a first voyage into space on April 12, 2018. The Federal Aviation Authority last week cleared an experiment by LiftPort that would use a mile-long tether attached to a balloon, something the company calls: "A critical step.''
Fears that an aircraft would crash into the elevator ribbon is just one concern. Space debris and terrorism are others.
ping
wait, wait, wait...
The Moon orbits the Earth. Are they proposing a static elevator between the two? I see this ending poorly, yet expensively at the same time.
sorry duplicate post: http://www.freerepublic.com/focus/f-news/1491158/posts
Just beam me up Scotty.
Better solution:
Just beam me up Scotty.
-----
Wonkavision
No, no, no...
Sattelites are already routinely placed in a "geosynchronous orbit." Sattelites stay in orbit because their inertia (improperly called, "centrifugal force") cancels out gravity. The closer to the earth they are, the faster they spin relative to the earth. So there is a point, hundreds of miles high, where the speed they are travelling matches the rotational velocity of the earth. This allows a satellite placed on the equator to stay precisely over the same point of land.
The idea would be to balance a ribbon stretching downward with extra mass above the orbital plane so that the mean mass of the satellite (including the ribbon) remains at the level of a geosynchronous orbit, but yet the ribbon reaches all the way to the earth. Then you can create a dumb waiter to lift small loads from the earth to the sattelite, where gravity is much, much weaker.
The problem with space flight is that nearly all your fuel is burnt just getting you to a low orbital level. Worse, the mroe fuel you carry, the heavier your ship is, so you have diminishing returns severly limiting the ability to travel into space. (Hence, massive rockets were needed to carry a lunar module scarcely bigger than a pickup truck.) If you can get as a high as a space elevator, the rest is a snap.
A more efficient method would be to wrap the cable around the moon. This way, there would be a second cable returning to earth, creating an up as well as down elevator of sorts. By installing little cable cars, just about anyone could visit the moon. I hope they consider this as I would like to visit several relatives who live there.
Perhaps all we need is a large rubber band...
Indeed.
That suggests no counterweight. Solar power is going to be tricky.
Hmm. Guess you're right. Guess that's why you're RightWhale!
If you're in a space hotel at 22,000 miles, and the cord breaks, what happens? You should just hover there until you can be recovered, right? Or would you be thrown out into space?
The article mentions a 600 ton satellite in synchronous orbit. What's the heaviest thing that's been put in a synchronous orbit to date?
But, having a fiber that has the tensile strength to do this at all is a big step. That was the stopper.
Doesn't this whole space elevator episode end with aliens and a 'cookbook'??? LOL!
I think I saw you posting on a recent thread here about a major breakthrough in production of carbon nanotube sheets that can be used to construct this thing. If not, I can provide a link.
Not in this lifetime. I'm just a space elevator fan. I think it's gonna work and we'll all wonder why we are building these big rockets for $100 billion.
Wouldn't it be great if a privately funded space elevator obsoleted all those govt funded rockets? Of course, we'd still need some heavy lift to get that 600 ton satellite up there!
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