Space Elevator: NASA Challange

While a lot of attention is being paid to nanomanufacturing and biology breakthroughs, somehow the revolution in materials sciences has lost popular attention. Carbon nanotubes, one of the most significant materials inventions ever is quickly making its way out of laboratories and into production environments. This article illustrates the degree to which carbon nanotubes could change our lives. Consider: A Space Elevator. The stuff of sci-fi. But as we've seen many times, a sci-fi idea frequently leads to real inventions. The carbon nanotube "cable" or "ribbon" from Earth to space needs to be over 37,000 miles long. How massive is that! How strong? Now it may be more than a few years until space elevators show up (and they certainly will due to the peculiarities and economics of the space launch business), but you'll see carbon nanotubes (and similar materials) much sooner in everyday products.

Original Online Reference

"LAS CRUCES, N.M. On a windy expanse of the Chihuahua Desert, the gangly 22-pound contraption began to climb up a thin carbon-fiber belt hung from a crane.

Directed toward the craft from the ground was an array of 135 mirrors to concentrate the blinding New Mexico sunlight to an intensity equal to 300 suns. The beam shined on the climber's high-efficiency solar cells. With a muffled whirring, it rose 35 feet.

Only 37,500 miles to go.

The Space Elevator Reference

"Climbers ascend a ribbon, 100,000 km long, strung between an anchor on Earth and a counterweight in space. Connecting Earth and space in a way never before possible, the space elevator will enable us to inexpensively and completely expand our society into space."

This site is a good spot to find ideas on the scientific, engineering, economic and policy challenges inherent in constructing a space elevator. Sounds exotic and farfetched, doesn't it? Yes it is. However, there are two major points to keep in mind:

The difficulty and cost to lift a significant amount of mass from the surface of the Earth to orbit is a major expense for space missions. All spacecraft designs are fundamentally limited by the amount of mass that can be lifted (by a given rocket) as well as the need to fit the spacecraft within the "fairing" (shell) of the "launcher's" (rocket) payload area. A space elevator or one of its variants (e.g., "space hook") could dramatically lower the cost of "Earth to orbit" as well as open up the constraints on spacecraft design.

Secondly, with the invention of carbon nano-tubes and the recent demonstration of the ability to make significant, long cables of carbon nano-tubes, one of the major engineering challenges is coming within reach of a solution: making a strong enough cable. Space "tethers", kilometers in length (but made of other materials) have already been test-deployed in space.


Bottom line: The economic necessity is there. The technology is coming of age. Building a space elevator will be an enormously difficult effort, with substantial risk. When the technology is more mature, I think we'll see good return on investment arguments from commercial, national, and international interests.

http://www.spaceelevator.com/