Space Elevator Low Down

Mike Nowak  10.24.05

With the flick of a switch, a searchlight beam illuminated a photovoltaic array, and a prototype space elevator called Snow Star One lifted off the ground. As the humble assemblage of solar cells, metal braces and off-the-shelf rollers rose slowly from the launch pad and up a long blue tether, a small crowd of spectators let out a boisterous cheer.

The contraption, designed by University of British Columbia undergrads Steve Jones and Damir Hot, didn't get very far -- it managed to wriggle its way just 15 feet up the 200-foot-long tether before stalling out. But as the first competitor in the inaugural Space Elevator Games, even that modest performance was enough to cause a quite stir in the still-embryonic space elevator community.

The games, sponsored by the nonprofit Spaceward Foundation, were held over the weekend at the NASA Ames Research Center in Mountain View, California. Teams competed in one of two events: a light-beam-powered robot climbing competition and a tether-strength contest.

According to many engineers, within a couple of decades it will be both possible and cost-effective to construct a fixed line from the Earth's equator to a satellite 60,000 miles out in space. The tether would likely be made of carbon nanotubes, a still-experimental material with the potential to be 300 times stronger than steel. According to current imaginings, elevator cars weighing up to 20 tons would go up and down, powered by high-intensity earthbound lasers aimed at photovoltaic cells on their undersides.

But with both nanotubes and beam power still a long way off, NASA has decided to try to speed things up by offering prizes to innovators who reach key development milestones in the next few years.

On the beam-power side, the challenge at the games was to use a 10,000-watt light source to send a robot 50 meters up the ribbon in under 50 seconds. For the tether competition, the goal was to construct a 2-gram tether that would be tougher than a 3-gram band made from a high-strength material called Zylon. The best-performing robot and tether, had they beaten those figures, would have earned their owners $50,000 each.

At the climbing competition, however, it wasn't just Jones and Hot that had trouble making it all the way to the top. A contingent of engineering students from the University of Saskatchewan did manage to send their climber 40 feet in the air. But none of the five other teams was able to corral enough power from the searchlight even to get off the launch gantry.

Despite the lackluster performance, however, most participants were upbeat about the proceedings. Hot, for one, was ecstatic. "It's the first beam-powered climber ever," he said. "So we're very proud. In fact, we're beaming."

Entrants in the tether-strength competition had a bit more luck, with one group narrowly missing the prize with a tether made out of Spectra, a material often used in body armor.

But despite this near-victory, Spaceward Foundation rep Marc Schwager claimed that real advancements in tether strength won't be possible until carbon nanotubes arrive on the scene -- something he hopes will happen as soon as next year's games.

Schwager, however, was sanguine about the outcome of the games as a whole. "I would have loved to see somebody win the prize," he said. "But what we're about is bringing attention and focus in this area, and that was successful. And pretty much all the contestants want to come back next year."

Spaceward board member Michael Laine, president of a Bremerton, Washington-based company called LiftPort that is seeking to commercialize space-elevator technology, noted that next year's games will up the ante considerably. While the already daunting thresholds will be set even higher, there will also be more money to entice competitors -- $100,000 for first prize, $40,000 for second and $10,000 for third.

"I think that next year is going to be big," Laine said. "It's going to be harder, but I think there's going to be lots of people that rise to the challenge. We're at the beginning of something really great."