In a few weeks, scientists from across the world will gather in the New Mexico desert to compete for one of the strangest — and most ambitious — technological competitions ever devised.
Some researchers will unveil robots, powered by solar panels, that will climb long lengths of cable. Others will demonstrate materials so light and strong that mile-long stretches of the stuff could be hung in the air without snapping. And some will highlight their plans to launch satellites carrying sets of mini-probes tethered together, to discover how they behave in space.
All these different projects are united by one extraordinary goal: to build a stairway to heaven. Each of the groups that will gather in New Mexico is competing to win a Nasa prize set up to encourage entrepreneurs to start development work on the technology needed to create a space elevator. Such a device would involve constructing a 36 800km cable that could pull men and goods into orbit without blasting them there on top of expensive, and dangerous, rockets.
”I think there are going to be lots of people that rise to this challenge,” said Michael Laine, president of the Washington-based company LiftPort, which will take part in the competition. ”We’re at the beginning of something really great.”
The key feature of a space elevator would be the use of a satellite that will orbit almost 37 000km above Earth. At this altitude, known as geostationary orbit, the orbital period of a satellite moving around the globe matches Earth’s rotation. The craft then hovers over a single spot on the equator.
However, a space elevator would have one extra key feature: a massive cable would be lowered from it to link it to the ground where it would remain fixed, like a tube line to the stars.
It sounds like science fiction. And indeed for the past 30 years that is how most people have viewed the concept of a space elevator, after the idea — originally put forward by the Russian scientist Yuri Artsutanov in 1960 — was made famous by Arthur C Clarke in his 1978 novel The Fountains of Paradise. At the time the book’s ideas were praised for their soundness, though scientists noted that the incredibly strong materials needed to build a space elevator were well beyond the technology of the day.
But science has made enormous advances since 1978, particularly in the development of incredibly light but strong substances that could be used to construct the space-elevator cable. In particular, the development of carbon nanotubes — made of highly robust webs of carbon atoms — has raised the promise that a space elevator may one day become reality.
And for Nasa that cannot come a moment too soon. Despite decades of putting rockets into space, the agency has never managed to make any real reductions in launch costs in that time. Hence its decision to back a competition to stimulate space-elevator technology.
”With a space elevator, Nasa could build probes that they weren’t able to do before; they could do new research on different applications of the space elevator,” said Bradley Edwards, an entrepreneur who played a key role in helping to set up the space-elevator competition.
Several United States companies and groups of university researchers, plus Canadian, German and Spanish scientists, have promised to bring their devices and put them through their paces at next month’s space-elevator competition. Prizes will be worth more than $400 000 in total, including one for a robot that will have to climb a 60m cable powered only by photovoltaic cells, and another for the creation of tether lighter and stronger than those made of materials now available commercially.
It promises to be a close-run thing. As New Scientist magazine reported last week, the best-performing robot last year managed an ascent of only 12m up a cable before it stalled, while no material came close to meeting the standards needed for building a space elevator. In short, we may have to wait a little bit longer than anticipated to build that stairway to heaven. — Guardian Unlimited Â