Firing the Imagination for a Space Elevator
The final frontier could be an elevator ride away, according to hundreds attending Space Elevator Conference 2009
This illustration shows how a space elevator might look attached to a ribbon of carbon nanotubes.
Today, a trip into space is a bone-crunching, rocket-roaring ride with a multi-billion dollar price tag. Tomorrow, it might be a smooth, 62,000-mile elevator ride, cheap enough for the masses. The journey would take place on a “space elevator,” which sounds like something out of science fiction: A ribbon from Earth that lifts crew and cargo up toward the stars. But, thanks to recent advances in technology, some scientists say this high-wire act isn’t as big a stretch as one might think.
August 13 through 16, hundreds of scientists, researchers, and space enthusiasts from all over the world gathered at Microsoft’s Redmond, WA, campus for Space Elevator Conference 2009 — an exploration of the technical, legal and social challenges of building an elevator to space. The fact is, ever since Russian scientist Konstantin Tsiolkovsky dreamed up the idea in 1895, the space elevator has lived primarily in the imaginations of writers such as Arthur C. Clarke, admits David Horn, a program manager on the Office Live Service Experience team and the conference’s organizer.
“It does sound a little like sci-fi but, hopefully, not for long,” Horn says. “The excitement about the space elevator is that the technologies we need to make this happen are very near.”
What paved the way to making this big dream a reality was the discovery of something very small. In 1991, researchers stumbled upon a new type of material called carbon nanotubes. This peculiar arrangement of carbon atoms turned out to be the strongest material ever tested. Some 100 times stronger than steel and a fraction of the weight, carbon nanotubes became the first plausible candidate for the space elevator’s ribbon.
Once a 62,000-mile-long cable is built — which isn’t unbelievable, if you consider that 72,000 miles of cable went into the Golden Gate Bridge, as Horn points out — the laws of physics make things fairly straightforward. Attach one end of your super-strong string to Earth, and drag the other end into space. The competing forces of gravity at the lower end and centripetal acceleration at the farther end keep the cable taut. With a taut cable fixed to a spacecraft in geosynchronous orbit over a single point on Earth, you have the basic ingredients for an elevator. Once in position, the cable could be scaled by mechanical climbers powered by lasers.
Next stop: Earth’s orbit
The space elevator would usher in an unprecedented era of exploration, Horn says. “The big factor that could potentially change the world is that it would reduce the access cost to space,” he says. “Instead of paying US$10,000 a pound to put something into orbit with a rocket, you could reduce that cost to $100 a pound or less.” Currently, only about seven percent of a rocket is payload, with the rest being fuel, he says. Ditch the volatile rocket fuel and the journey becomes much safer, too.
The same yearning for the stars that put the space elevator into the pages of novels bit Horn when he was a boy. One book on astronomy and he was forever hooked, though poor eyesight dashed his dreams of becoming an astronaut. He still reads about astronomy and space travel, and he first learned about the space elevator a few years ago in a book he finished on a beach in Mexico. The concept sounded a little out there, and he didn’t think much about it until last year, when Microsoft hosted the Space Elevator Conference for the first time.
The disproportionately large number of Microsoft employees who also have the space bug was a big factor in bringing the conference to campus, Horn says. “It’s kind of in the same vein that we have more cricket teams than most companies in North America,” he says. Early last year, the Space Elevator Conference chairman made a presentation to several Microsoft Research teams. A few employees approached him afterward about helping out, which led to Microsoft playing host to the 2008 conference. It became a natural next step to bring the conference back again this year, Horn says.
Horn dropped everything he was doing to check out the conference. “I was intrigued,” he says. “After seeing everything last year, I just said, ‘Wow, this is close to becoming a reality.'” He volunteered to organize this year’s conference, which is the seventh annual event focused on tackling the remaining obstacles.
Although no longer a mere dream, many challenges remain before anyone hitches a ride on a space elevator. Take those carbon nanotubes that are supposed to make a space elevator plausible — so far, the only ones that have been produced are just a few centimeters long. Then, there are the political and diplomatic challenges posed by the elevator, not to mention concerns about lightning, terrorism and floating space junk.
Still, incremental progress is being made, and panels at the conference took stock of it as they looked ahead. But the conference isn’t all nitty-gritty details — firing the imagination is also on the agenda. Before the official opening, the conference hosted a free presentation about the space elevator concept. Horn says that event was family-focused, perhaps capturing the sense of wonder Horn had as a boy, viewing Jupiter through a telescope.
“One theme this year is to get more communities involved, more schools involved, more kids involved,” Horn says. “By the time this becomes a reality, they’ll be the ones building it. So, with this event, we’re saying, ‘Come spark the imagination of your kids or yourself. Come see what’s possible.'”