Six teams are vying for a share of the $1 million in prize money up for grabs at the NASA-sponsored 2007 Space Elevator Games taking place this weekend in Farmington, near Salt Lake City, Utah, US.
Now in its third year, the competition aims to spur innovation in technologies that might one day be used to build a space elevator – a cable anchored to the Earth and stretching all the way into space, together with a vehicle able to climb it to carry things into orbit.
Building a cable strong enough for a space elevator is beyond current technology. So one of the two challenges that make up the Games involves designing and building a cable stronger than anything commercially available today.
Two teams qualified for the tether challenge - Astroaraneae, made up largely of Aerojet employees, and a team from MIT. The teams' tethers will be stretched on a machine until one breaks. The winning tether will then be pitted against the "house tether", made of off-the-shelf material and weighing 3 grams. The challenger is limited to a weight of 2 grams, and will have to prove itself at least 50% stronger than the house tether, which survived more than 1600 pounds of force last year.
It is a small field of competitors for this part of the competition. "That says something about the difficulty level and the challenge for sure," says Michael Remington of Astroaraneae. "But it's something that's got to be worked on or else it will never happen, and you've got to start somewhere."
The tether challenge is set to begin at 5 pm MDT on Saturday (2300 GMT).
The other contest, called the beam power challenge, is to build a vehicle that can climb a cable without the burden of an onboard power source. Like a future space elevator, it has to rely on power transmitted below in the form of laser light, microwaves, or some other type of "beamed power".
On Thursday, several teams attempted to qualify for the beamed power competition. The teams that qualified are the Kansas City Space Pirates (click on the image below to watch a video taken from a camera on their climber during their successful qualification attempt); the Technology Tycoons; a team from the University of British Columbia; and one from the University of Saskatchewan.
The University of Saskatchewan's vehicle was the top performer in the 2005 and 2006 competitions, but failed to climb fast and high enough to win the prize money. They are expected to put in a strong showing again this year with their design, which uses a 9 kilowatt infrared laser for power.
On Friday, the crane was set up, and the Kansas City Space Pirates wanted to make their run for the beam power prize. Their vehicle uses solar power cells, supplied with sunlight from an array of 19 mirrors on the ground. But the winds proved too strong, which is dangerous for the vehicles, as Ted Semon of the Spaceward Foundation, and writer of the Space Elevator Blog.
The wind shakes the cable and the climber vehicles, he says: "We had one minor disaster on Monday," when some teams were doing practice runs. One vehicle "started shaking so bad some of the solar cells fell off".
That was not the biggest disaster of this year's competition. A truck hit a trailer carrying equipment for a team from McGill University, which planned to use microwaves to power their climber. The accident smashed a lot of their parts, and even though they tried to rebuild them, they were unable to qualify.
Rain is expected on Saturday, and cloudy weather on Sunday, which could prevent the beam power challenge from going forward, since three of the four qualifying teams rely on solar power. There has been talk of extending the competition another day to Monday, but many of the teams cannot stay, so it is unclear whether this will be possible.
On another note, I've heard some grumbling here about the way the games are being handled. The registration fee has gone up to $2500 from $500 last year, they say, which is a big deal for a competition in which many of the teams are bankrolled with funds from team members' personal bank accounts. Another beef is that the rules are unclear and frequently changing.
On Friday, I wandered around and visited some of the teams and I'm impressed by the enthusiasm and ingenuity on display here. I hope the weather holds up so that we can see the beam power vehicles in action on Saturday or Sunday, but that's up to the vagaries of Mother Nature.
http://www.newscientist.com/blog/space/ ... begin.html
Just don't tug on the wire, unless you want a megatonne space station falling on your head
) this conception would not only need to support it's own weight (the total mass of it from the ground up to 0g altitude multiplied by an average of gravitational force, that's f=m(1g->0g)*g/2) but also have some system in place to account for any additional weight when it would operate. To put it in a different perspective: atomic bonds of the material used for the tether should be strong enough to hold the tether itself together. Perhaps they've just fallen hard on their heads and think since there's 0g where one end of it will be stationed, that will somehow magically negate any gravitational forces on that part that's not in 0g and affected by Earth's gravity 
Obviously, some active system (rockets, whatever) to negate that effect should be set-up on the upper (0g) station. Only one problem there... that'd put even more strain on the tether, wouldn't it? And unless they're in possession of some to me unknown material that fell out of the Enterprise last time they were here saving the whales, that would be quite impossible IMO, whatever the target tether thickness. Also, one should not forget that Earth rotates. So that upper station would have to not only negate all the dead weight that's in Earths gravitational field plus any freight weight while it's affected by gravity too, but would also have to keep a geostationary orbit (that's essential to keep the dead weight to minimum and the tether as short as possible). I guess they could do it using some sort of centrifugal movement system, but again one little detail... centrifugal has "center" in and the ground level isn't the center of the Earth. So additional active systems would have to be used on the upper station to negate for that fact. And you have to build it, meaning you'd have to send all that weight up there in the first place. Then, presumably, it would be expected that thing would be able to function for at least a few months, burning precious fuel while it maintains its position... blah, blah,... sorry folks, I just don't see this thing ever happening. It's an interesting concept though, just not practical enough for Earth based systems or until we start manufacturing cheap anti-gravity engines. And we all know that research is going on rather well 
