Space elevators are no longer going to be just a figment of imagination but scientists are predicting that they may be a reality by 2035. A space elevator is not a tower or building but a durable and flexible cable originating or tethered on earth as well as a geostationary space station. A climber, mechanical in nature, will use rollers or magnetic levitation along the cable, to carry people or heavy equipment into orbit. Just as the space shuttle introduced space rockets which can be reused, space elevators would function as a tethered space rocket which would transport people and equipment into space. Read on to find out more about this futuristic space travel concept:
Space elevators and their use
The idea of space elevators has been around since 1895 when Tsiolkovsky, a Russian scientist imagined a tower which was 35,800 kilometers tall, reaching the geostationary orbit, and would be able to carry loads to space. The present concept is the same, except that in place of a tower, it would be a cable which would be tethered at both ends – on earth as well as in space.
The cost of building a space elevator is in billions, but scientists say that the cost would be offset by the much cheaper space travel that it would provide to people all over the world. The length of the cable is estimated to be about 100,000 km long, stretching past the geostationary orbit.
Travelling via a cable seems precarious, but the space elevator cable would be extremely strong, able to carry approximately 7-20 tons of payload at one time, according to the IAA or International Academy of Astronauts. The tether would be weighed down by an anchor of approximately two million kg or about the weight of 170 school buses combined. This amazing space elevator would enable loads to be sent up to space, every couple of days, changing the entire concept of space travel.
Cost-effective space travel
Right now, it costs $20,000 for every kilogram of weight sent into space, but with space elevators, it could be as less as $500 per kilogram, according to IAA.
According to the lead researcher, who prepared the report for IAA, space elevators can decrease the launching cost of satellites up to 99%!
Another company which is developing the space elevator concept, (Thoth), aims to build one which is only 20 kms high, just enough to launch space missions which would cost much less fuel.
Both IAA and Thoth, face the problem of finding the right material for the space elevator they are planning to build.
What kind of materials would be used
It goes without saying that the material required to construct space elevators has to extremely strong, flexible and dense. As gravity decreases farther from the surface of the earth, the cable has to have enough tensile strength to support approximately 5000 km of itself.
At first, the ultra flexible but tough carbon nanotube was chosen by the engineers, but it was found to be unfit, after a study conducted by Polytechnic University, Hong Kong. Diamond nanothreads, which were discovered by researchers in 2015 could also be chosen as the best material.
In other words, the right material does not exist, as of now, but it is expected that it will come into being before 2030.
The Japanese effort
The Japanese too are trying to construct space elevator. Shizouka University’s Star-C orbiter will test the material Kevlar, whether it would work as the tether. They will be testing whether a tether climber would function well on Kevlar. This would be a breakthrough in the research of space elevators.
Space elevators will harness solar power
Space elevators will be able to harness a huge amount of solar power. This would be possible due to the solar panels in space, where the light from the sun is unfiltered, and compared to earth, much more solar energy is available. The harnessed light can just radiate solar electricity down to earth, and bypass power lines totally.
A sci-fi anime “Gundam oo” showed a world in which humans depended on some space elevators to power the planet. Sometimes, fiction becomes reality and maybe this is what we have in our future!