From sci-fi to reality, here is how space elevator technology will change the world of space tech!
With billionaires Sir Richard Branson and Jeff Bezos making their way to outer space, space travel became a hot topic in 2021. The increased interest in space is also evident in the fact that space infrastructure companies saw US$14.5 billion in investments in 2021, a 50% increase from 2020.
As space tourism and asteroid mining are offering companies a new source of revenue, it is only natural that people are attempting to make space travel cheaper, easier and faster. Introducing space elevators—tall, thin tethers that would deliver people, satellites and goods between Earth and outer space. Imagine an elevator in a skyscraper the size of a train that takes you to space instead of the highest floor…… how cool is that?
Let’s take a look at how this tech works, its benefits and companies that are working towards creating space elevators.
What is a space elevator?
The space elevator was first described in 1985 by the Russian rocket scientist, Konstantin Tsiolkovsky. He explained it as a really tall building extending from Earth’s surface to the geostationary orbit (a circular orbit 35,785 km above the equator, where the satellites move in the same speed as Earth’s rotation).
The modern idea of the space elevator is essentially a tether or a cable that would be connected to an anchor on Earth and a counterweight space station. Much like Tsiolkovsky’s idea, the space station end of the elevator would also be located in geostationary orbit. The gravitational pull experienced by the tether would be balanced by the centrifugal force (which pushes the station outwards) on the counterweight space station in the geostationary orbit. While normal elevators have moving cables, the space elevator’s cable would be stationary. The space elevator would rely on devices called crawlers, climbers or lifters going up and down along the cable.
Who are building space elevators?
All that we previously discussed might seem like something out of a sci-fi film, but there are companies that are working on making space elevators a reality. Canada-based, Thoth Technology, patented its space elevator design back in 2015.
In 2018, a team of engineers from Japan’s Shizuoka University’s Faculty of Engineering created a scale model of a space elevator. The university later joined hands with the Japanese construction company Obayashi Corporation to work on the project STARS.Me (Space Tethered Autonomous Robotics Satellite-Mini elevator). The project involves creating a space elevator between two small satellites.
Obayashi Corporation has been working towards making space elevators a reality since 2012. They have proposed a space elevator that would have the capacity of 30 astronauts plus cargo by 2050. The company is currently in the testing phase and plans to begin construction of the elevator by 2025.
Benefits of space elevators
Now that we know how the technology works and the companies trying to make it happen, the next big question is why? We have already briefly mentioned that space elevators can reduce costs and time taken for space travel. Once space elevators are in operation, the costs of taking hardware to space would be US$100 per pound. Currently, the cheapest way to take hardware up to the space station is to use SpaceX’s rockets, which cost US$6000 per pound.
Besides that, there are other ways in which space elevators would advance space tech. The elevator will cut fuel consumption, and will also be more sustainable than rocket technology. Rockets tend to create “space junk”, or human-made objects that have been left in space. According to the U.S. National Aeronautics and Space Administration (NASA), more than 27,000 pieces of orbital debris have been tracked as of 2021. Space elevators would be more sustainable, given that rockets would create debris when they break down. It would also make space travel safer since it eliminates the threat of rocket engine explosions.
Concerns surrounding the use of space elevators
Of course, this technology is not threat-free. Space elevators pose a glaring problem—there is a possibility that the tether snaps. This would lead to pieces of the tether falling down to Earth’s surface, causing major destruction everywhere they land. Some pieces of the tether might not even make their way onto Earth’s surface and end up stuck in Earth’s orbit, adding to the space debris problem that the elevator intends to fix.
Orbital debris is also a major threat to the functioning of the elevator in the first place. Since the space elevator is anchored to Earth, it is static and immovable. If it is hit by space junk, it could get seriously damaged.
While these dangers exist, it is not as if scientists haven’t thought out solutions for them. In 2003, NASA-funded physicist Bradley Edwards came up with a design for the space elevator that would be really wide at the top and tapered towards the bottom. This would prevent space debris from doing anything but leaving small bullet holes in the tether, which could be repaired.
Despite Edwards’ research and unique model, space debris remains a real threat to the development of space elevators to this day. Once space’s waste management problem is dealt with, the space elevator technology could actually open doors for further space exploration.
Header image courtesy of Obayashi Corporation’s website