By Dean Irvine for CNN
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LONDON, England (CNN) -- Posted September 18, 2006
A radically different way to reach outer space -- the space elevator -- may finally be getting off the ground floor thanks to recent huge advances in technology.
Traveling thousands of miles into the cosmos up a length of super-strong material, it is believed that the space elevator could revolutionize space exploration by providing an affordable means of transporting satellites, space station supplies, and one day even tourists into space.
The concept of the space elevator was first mooted by Russian engineer Yuri Artsutanov in the 1960s, and until recently has remained more familiar to fans of science fiction, such as Arthur C. Clarke's1979 novel, "The Fountains of Paradise."
Previous ideas, such as lassoing one end of the elevator cable to an asteroid in geo-stationary orbit, haven't helped the concept to be accepted as a serious project.
However there is a growing recognition that what once seemed a starry idea is not merely feasible but probable.
"It's a very credible idea; there is nothing wrong with the physics of it. If enough funding is found, it's possible we could see a space elevator in about 20 years," Robert Cassanova, director of NASA's Institute for Advanced Concepts told CNN.
The basic premise involves an elevator that would travel from its base station up a cable tethered at the other end to a counterweight in geo-stationary orbit. Satellites, supplies or astronauts would be loaded onto the elevator climber at the offshore platform anchored on the equator, where risks of storms, lightning and hurricanes are minimal.
The main stumbling block in the past has been finding a material strong and light enough to reach up to 62,000 miles into space.
Space elevator expert Dr Bradley Edwards of the Spaceward Foundation is a pioneer in space elevator design. He believes that the current and ongoing developments in carbon nanotube technology holds the key to the project.
"Previously the material challenges were too great. But now we're getting close with the advances in creating carbon nanotubes and in building machines that can spin out the great lengths of material needed to create a ribbon that will stretch up into space," he told CNN.
Edwards envisions a paper-thin ribbon of approximately one meter in width composed of multiple strings of nanotubes - essentially sheets of graphite, a lattice of carbon - seamlessly rolled into long tubes that are only nanometers in diameter.
To the naked eye it would appear semi-transparent and no thicker than that width of a pencil, yet would be incredibly strong and light. Recently produced carbon nanotube fibers have been found to be over 20 times stronger than steel wire.
A deployment satellite would send up the initial string of ribbon, which would be added to by climbers carrying further lengths of carbon nanotubes until it was the required width. The ribbon would he held taut by the motion of the weight -- much like the way in which a weight on the end of a string stays taut when spun.
Edwards together with company Xtech, plus other businesses, are working to perfect the material, but he believes that the rest of the technology is already available in certain forms.
"Power beaming from lasers has been used by the space shuttle before. There are currently high-powered lasers made by Boeing that would not need too much adaptation to power the electric motors of the elevator climbers, via solar panels," he said.
Propelling the elevator at approximately 120mph, it could be an all together more serene way to enter space than being strapped to the top of a rocket.
The race is already on to develop a working prototype climber. Teams from across the world are set to compete for the $400,000 first prize in the Space Elevator Games at the X Prize Cup this October in Las Cruces, New Mexico.
Without the enormous expense of using rockets, Edwards believes the space elevator could cut the huge costs of sending space crafts and satellites into orbit.
He estimates that sending material into space on the elevator would cost approximately $100 per kilogram, compared to the shuttle costing between $10,000 and $40,000 per kilogram.
By slashing the costs, the cosmos would open up to more countries and a greater number of commercial projects.
"Solar powered satellites, which are still being developed and hugely expensive, would become viable and cost efficient. More money could be spent on the payload than the logistics of getting it into space. BP Solar has shown a strong interest," said Edwards.
"Developing countries could use solar satellites to produce clean energy or launch their own telecommunications satellites to develop their economies."
Without the brute force of chemical reactions, the shaking of lift-off and effects of G-force, entering space as a tourist on the elevator would be a more pleasant experience, as long as there wasn't any incidental muzak.
"Without too much trouble the climber could have a module that carried passengers. They would reach low earth orbit after about three hours. At that height you wouldn't have the effects of weightlessness, so you could enjoy dinner with an incredible view."
It is believed that the elevator could also act as a sling-shot to send space craft towards the moon, Mars or beyond.
NASA funded Edwards for three years, but only last year awarded $28m to companies researching the next generation of space shuttle. Why haven't they followed up their initial interest?
"We continue to offer moral support to Edwards and his space elevator project, but currently there are a number of details that we'd still like to see worked out," Cassanova told CNN.
Edwards views the future of space development as contingent on commercial application and private funding.
"NASA spends around $16bn a year on their space program, with the cost of sending up one space shuttle at about $500m. With such high costs, it is understandable that they need to use mature technology that they know works. They are naturally risk-adverse.
"Commercial development and private funding is crucial to the future of space exploration. The space elevator would make space accessible for so many more people, so we believe the funding will come once the benefits are realised. Once we've proved the technology works, we firmly believe that the project will open up space for generations to come."
Dr Edward's vision of the space elevator would travel 62,000 miles into space along a carbon nanotube ribbon
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