The idea of a space elevator made of ultra-strong carbon nanotubes has been talked about a lot over the past several years, but recently some research groups have begun to investigate the idea as a real possibility. Most recently, scientists from Japan have started an organization called the Japan Space Elevator Association, and they plan to host an international conference in November to draw up a timetable for the machine.
Not only are the scientists making this idea sound technologically realistic, but they also estimate that they could build the space elevator at a cost of just 1 trillion yen, or about $9 billion (sounds like spare change compared with the US government’s recent $700 billion bail-out of failing financial institutions).
Anyway, the space elevator would be made of carbon nanotube cables tethered to the ground. They would run into space and attach to a satellite docking station in geostationary orbit above the Earth. The cables would need to be about 22,000 miles (36,000 km) long, and would need to be about twice the distance to the docking station.
The space elevator concept is becoming feasible recently due to the rapid advances in carbon nanotube technology. To build the space elevator, carbon nanotubes would need to be about four times stronger than the current strongest carbon nanotubes – which is about 180 times stronger than steel. Since carbon nanotubes’ strength has improved 100 times over the past five years, this goal definitely seems within reach.
To power the space elevator, the researchers are considering using technology similar to that used in bullet trains. “Carbon nanotubes are good conductors of electricity, so we are thinking of having a second cable to provide power all along the route,” said Yoshio Aoki, a professor of precision machinery engineering at Nihon University and a director of the Japan Space Elevator Association.
One of the biggest advantages of traveling via space elevator rather than space shuttle is the much lower cost. Because it doesn’t require huge amounts of rocket fuel to overcome Earth’s gravity, the elevator could use 100 times less energy than is needed to launch a space shuttle.
When complete, the space elevator could carry both people and supplies. It could also be used for innovative projects such as carrying large solar-powered generators into space that could provide power for earth-based activities, or barrels of radioactive waste that could be dumped into outer space when we have trashed our own planet.
“Just like travelling abroad, anyone will be able to ride the elevator into space,” Shuichi Ono, chairman of the Japan Space Elevator Association, said.
A handful of other groups are working on space elevator projects, including NASA and the LiftPort Group. Competitions and prizes such as Elevator 2010 are also inspiring research and engaging the public.