Friday, October 3, 2008

'Space elevator' to take mankind into orbit

LONDON, England (CNN) -- A new space race is officially underway, and this one should have the sci-fi geeks salivating.

The project is a "space elevator," and some experts now believe the concept is well within the bounds of possibility -- maybe even within our lifetimes.

A conference discussing developments in space elevator concepts is being held in Japan in November and hundreds of engineers and scientists from Asia, Europe and the Americas are working to design the only lift that will take you directly to the one hundred-thousandth floor.

Despite these developments, you could be excused for thinking it all sounds a little far-fetched.

Indeed, if successfully built, the space elevator would be an unprecedented feat of human engineering.
A cable anchored to the Earth's surface, reaching tens of thousands of kilometers into space balanced with a counterweight attached at the other end is the basic design for the elevator.

It is thought inertia (the physics theory stating that matter retains its velocity along a straight line so long as it is not acted upon by an external force) will cause the cable to stay stretched taut, allowing the elevator to sit in geostationary orbit.
The cable would extend into the sky eventually reaching a satellite docking station orbiting in space.

It is hoped the elevator will transport people and objects into space, and there have even been suggestions that it could be used to dispose of nuclear waste. Another proposed idea is to use the elevator to place solar panels in space to provide power for homes on Earth.
If it sounds like the stuff of fiction, maybe that's because it once was.

In 1979, Arthur C. Clarke's novel "The Fountains of Paradise" first brought the idea of a space elevator to a mass audience. Charles Sheffield's "The Web Between the Worlds" also featured the building of a space elevator.

But, jump out of the story books, fast-forward nearly three decades and Japanese scientists at the Japan Space Elevator Association (JSEA) are working seriously on the space elevator project.

JSEA spokesman Akira Tsuchida told CNN his organization was working with U.S.-based Spaceward Foundation and a European organization based in Luxembourg, to develop an elevator design.
The Liftport Group in the U.S. is also working on developing a design, and in total it's believed over 300 scientists and engineers are engaged in such work around the globe.

NASA is also holding a $4 million Space Elevator Challenge, to encourage designs for a space elevator than can work.

Tsuchida said the technology driving the race to build the first space elevator is the quickly developing material carbon nanotube.
It is lightweight and has a tensile strength 180 times stronger than steel cable. Currently, it is the only material with the potential to be strong enough to use to manufacture elevator cable, according to Tsuchida.

"At present we have a tether which is made of carbon nanotube, and has one third or one quarter of the strength required to make a space elevator. We expect that we will have strong enough cable in the 2020s or 2030s," Tsuchida said.

He said the most likely method of powering the elevator would be through the carbon nanotube cable.
So, what are the major logistical issues keeping the space elevator from being anything more than a dream at present?

Massachusetts Institute of Technology (MIT) Aeronautics and Astronautics Professor, Jeff Hoffman, said designing the carbon nanotube appeared to be the biggest obstacle.

"We are now on the verge of having material that has the strength to span the 30,000 km ... but we don't have the ability to make long cable out of the carbon nanotubes at the moment.

"Although, I'm confident that within a reasonable amount of time we will be able to do this," he said. Do you believe mankind could become a space faring species in your lifetime?
Tsuchida said one of the biggest issues is acquiring funding to move the projects forward. At present there is no financial backing for the space elevator project and all of JSEA's 100-plus members maintain other jobs to earn a living.

"Because we don't have a material which has enough strength to construct space elevator yet, it is difficult to change people's mind so they believe that it can be real."

Hoffman feels international dialogue needs to be encouaraged on the issue. He said there would be a number of legal considerations that would have to be taken into account.

"This is not something one nation or one company can do. There needs to be a worldwide approach."

Other difficulties for space elevator projects include how to build the base for the elevator, how to design it, and where to set up the operation.

Tsuchida said some possible locations for an elevator include the South China Sea, western Australia, and the Galapagos Islands in the Pacific Ocean. He said all of those locations usually avoided typhoons, which could pose a threat to the safety of an elevator.

"As the base of space elevator will be located on geosynchronous orbit, space elevator ground (earth port) station should be located near the Equator," he said.

While JSEA has set a time frame of the 2030s to get a space elevator under construction -- and developments are moving quickly -- Hoffman acknowledges it could be a little further away than that.

"I don't know if it's going to be in our lifetime or if it's 100 or 200 years away, but it's near enough that we can contemplate how it will work."

But, the space elevator is a matter of when not if, and will herald a major new period in human history, says Hoffman.

"It will be revolutionary for human technology, and not just for space travel. That's why so many people are pursuing it. This is what it will take to turn humans into a space bearing species."

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