Far out idea isn’t so far out
The most recent achievement in space exploration was the Mars Curiosity Rover, which is successfully exploring the surface of the Red Planet and testing out all of its instruments for over a month now. This achievement has been very exciting for many scientists and researchers, but it also raises the question of when the next breakthrough in human space exploration will be.
With the shuttle program over, and not much funding for NASA’s human space flight program, the private sector is gradually taking over space exploration with a handful of companies working on developing their own rocket propulsion systems that may eventually be used in conjunction with NASA. But there is another radical idea that has been poking its head in and out of the spotlight: the space elevator.
First dreamt up in 1895 as a tower that one could walk out of and stay afloat, the concept of the space elevator has come a long way. The idea is to launch a 100,000 km long ribbon cable up into space where it would be free from the pull of gravity. The lower end would be anchored to a mobile station on earth probably somewhere in the equatorial pacific. A counterweight would be attached to the top end, keeping the cable taut. Think of it like continuously swinging a ball around on a string attached to your hand. Your hand is the earth, the string is the cable, and the ball is the counterweight.
Once the elevator is in place, cars known as ‘climbers’ or ‘lifters’ would be able to climb up the cable using a combination of solar energy and ground-based lasers. These climbers could transport cargo, satellites and even tourists into space. So what are the disadvantages? The big one is cost. Overcoming the earth’s gravity is not an easy thing to do, and it is very expensive. The higher you climb in the atmosphere, the less gravity pulls down on you making it easier to go up, but harder to get started.
The cost for launching anything into space during the days of the space shuttle was around $10,000 per pound, making it very expensive to do anything practical. The space elevator’s cars that can climb up the cable would eliminate this problem, possibly bringing the cost down to $500 per pound.
Granted it would be much slower than a rocket launch, but there could potentially be several different climbers going at once. This would also be a much safer process, since you don’t have to worry about any fuel exploding during launch, and you could carry a much heavier payload up into space.
The concept of the space elevator has had its ups and downs. It gained public attention in 1979 when two sci-fi books about the concept were released – Arthur C. Clarke’s Fountains of Paradise and Charles Sheffield’s Web Between the Worlds. The major problem with the idea was there was no material strong and light enough to support its own weight when it was that high up.
A scientific breakthrough finally came in the early 1990’s with the development of carbon nanotubes, a wonder-material that has made its mark in many other industries since its development. This is the material that comes closest to meeting the space elevator’s need for a cable that is strong, yet lightweight. Once the carbon nanotubes entered the game, people started taking the idea of a space elevator much more seriously.
Michael Laine was one of these people. He started the company, Liftport Group, in 2003 with the goal of making the space elevator a reality. After some research and testing, it was concluded that the space elevator could not be built with current technology.
Carbon nanotubes are unable to be made long enough yet, and the technology still needs some major refining before it is used for a space elevator. But Liftport has recently re-entered the spotlight, this time with a new idea: a space elevator on the moon. Being much smaller than earth, the moon has less gravity, meaning that the cable can be significantly shorter.
This idea is completely doable with current technology, said Liftport. And, clearly, they aren’t the only ones who think so. Liftport recently announced their project on Kickstarter, a crowd-funded website for new ideas. While the project’s initial goal was to raise a meager $8000 to get things going, funders and supporters of the idea ended up pledging over $110,000.
The lunar elevator could serve as a trial run for the earth elevator and would also make it easier to transport cargo to the moon. As with any major scientific undertaking, there are still many obstacles that must be addressed before the space elevator becomes a reality.
But once built, the opportunities are endless. It could greatly enable further space endeavours, such as asteroid mining, space colonization, microgravity research, satellite deployment, and space tourism. As far-fetched as the idea if a space elevator may sound, this is something that may actually happen in our lifetime.
Arthur C. Clarke once said that the space elevator could be built 50 years after everyone stops laughing.