A University of Saskatchewan-built laser-powered robot climber scaled a 100-metre tether in less than a minute, but failed to beat the time required to claim a $500,000 US NASA-sponsored prize.

For the third year in a row the University of Saskatchewan Space Design Team (USST) had the fastest vehicle in their competition at the 2007 Spaceward Games, a competition that wrapped up Monday in Salt Lake City, Utah. And for the third year in a row they fell just short of the prize money.

According to the rules of the 2007 Spaceward Games Beam Power Challenge competition, the robot climber had to scale 100 metres with an average speed of two metres per second. The USST's robot climbed the tether in 54 seconds.

Ted Semon, a spokesman for the Spaceward Foundation, the group sponsoring the competition, said the university's efforts were another step forward in advancing the technology.

"Unfortunately, the results were like last year — USST was just a few seconds too slow to claim the prize," wrote Semon in the non-profit organization's blog.

"But they greatly increased their speed over last year [approximately double] and are fulfilling NASA's and Spaceward's goal of advancing the state of the art."

The Saskatchewan team's entry was unique because it was powered from the ground by a laser.

"It's like trying to point a laser pointer at a target 200 feet away and keep it steady," team leader Clayton Ruszkowski told CBC News earlier this summer.

To claim the prize money, the winning team must come up with the best design that also passes a stringent set of requirements — which are increased each year of the contest. Last year University of Saskatchewan team's entry was 0.04 metres per second too slow to win the prize.

Teams from Kingston, Ont.-based Queen's University, University of British Columbia, Montreal-based McGill University and the University of Alberta also competed in the competition, with the team from UBC making it to the final eight teams along with Saskatchewan's team.

The contest is divided into two competitions, each with a $500,000 US prize provided by NASA. The more visible challenge is the attempt to build the best possible space elevator climber prototype, which is where the Canadian teams competed.

The other challenge was to develop the material that makes up the tether on which the elevator rides. A team from the Massachusetts Institute of Technology entered a tether made up of carbon nanotubes, but the tether failed to hold up when pressure was applied. They were one of two teams that entered the competition; the other team withdrew during the competition.

The prize money for both competitions will be rolled into next year's prize. NASA began sponsoring the Spaceward Games in 2005 to spur breakthroughs in material science, building cables for the elevators.

Not rocket science

A space elevator doesn't use rocket propulsion. It's basically a physically stationary tether between the ground and an object in space, and a set of vehicles that can travel to space and back, moving on the tether using electric motors. Spaceward Foundation, which sponsors the event, says on its website that the term "elevator" is a bit misleading, since it's better described as a much larger gondola-type ski lift that moves vertically.

The idea of a space elevator, popularized by science fiction writer Arthur C. Clarke in the 1970s, was first proposed by Russian scientist Konstantin Tsiolkovsky. It has been championed as a way to bring space ships into orbit without the cost or risk associated with launching a rocket.

In theory, a space elevator would convey people or cargo along a 100,000-kilometre-long cable or ribbon anchored to the ground at one end and an orbiting space station at the other.