193 - Space Elevator 2010 Contest -
http://www.msnbc.msn.com/id/5792719/
" ‘Elevator:2010’ aimed
at encouraging
technology development
One of the marquee events in a proposed space elevator competition would be a climber race, shown in this artist's conception. The mechanical climbers would be required to lift a payload up a 60-meter cable, with power provided by an intense light beam shining on photoelectric cells.
The project, spearheaded by the California-based Spaceward Foundation, would focus on innovations in fields that could open the way for payloads to be lifted into space by light-powered platforms. Such platforms, also known as climbers, would move up and down superstrong ribbons rising as high as 62,000 miles (100,000 kilometers) above Earth's surface.
If space elevators could actually be built, the cost of sending payloads into space could be reduced from $10,000 or more per pound (455 grams) to $100 or less — opening up a revolutionary route to the final frontier. Like the X Prize for private spaceflight, Elevator:2010 is aimed at jump-starting the revolution
"We firmly believe that the set of technologies that underlie the infinite promise of the space elevator can be demonstrated, or proven infeasible, within a five-year time frame," the Web site for the competition declares. "And hence our name. Elevator:2010. We promise to get an answer for you by then.""
In order to work, the elevator's ribbons would have to be made of materials stronger than any that exist today; carbon nanotube composites are the current favorites. Conventional rockets would launch components of the elevator, which would be anchored to an Earth station to form a bridge to outer space.
Most of the current schemes call for the climbers to be powered by sunlight and/or intense artificial light focused onto photoelectric cells. The climbers would ride on the ribbons like rail cars."
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NOT ROCKETS !!!! ROCKETS ARE NOT FOR COMMERCE !!!
Usually, there is a maximum equatorial ground track distance that falls within an acceptable margin from the desired sub-point. Since geosync satellites tend to drift in one direction, station-keeping usually means using a thruster of some kind to position it at the "uphill end" and let it drift to the "bottom end", re-firing the thruster "pushing" the satellite back to the "up hill" and letting it drift once again over and over for the life of the vehicle. The cross-track drift ends up looking like a figure eight plotted against the ground. This figure eight gets bigger with age as the drift grows. Again, Delta-Vs can keep your bird on station for the life of the satellite.
OTOH, with a Space Elevator, you don't have these luxuries. You must not induce a vibration (or standing wave) in this structure. Remember the Tacoma Narrows Bridge? Even if your structure is strong enough to span the "gap", (23,000 miles in one heck of a gap) you must take into account vibrational stress.
The other issue is the electrical potential that will be present between the top of the elevator and the bottom. How do we discharge/ground that safely?
I know I am sounding like a wet blanket here, but like the Orion project, IMHO, the Space Elevator (although intriguing), will remain a "paper" project.
NOT ROCKETS !!!! ROCKETS ARE NOT FOR COMMERCE !!!
We are using rockets for commerce as we speak. Someone is making money for getting all those satellites up there.
BTW, Look for part two (and possibly a part three) to my previous post tonight and tomorrow, should there be a part three.