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Honestly, it’s really more of a stratosphere elevator than a “space” elevator, but a new space elevator concept from Canadian company Thoth Technology has some in the space industry buzzing. It’s an odd design, even by the standards of lifts to the heavens, and it makes some key compromises that make it less useful than a traditional space elevator design. But those very compromises mean that it might just be feasible enough to make a debut in the real, actual world.

Space elevators usually refer to devices where cars, or “climbers,” pull themselves up a long, flexible metal ribbon stretching from Earth to geosynchronous orbit, and held taught by the centrifugal force of a huge anchor weight at the end. The idea is to make “launch” to orbit several orders of magnitude cheaper and safer, so next-gen space projects like the colonization of Mars might become practically possible. A space elevator would allow us to power a launch to space with electricity, rather than explosive chemical energy, and thus beat the majority of Earth’s gravity for far, far less investment.

The design features a takeoff and landing strip at the top.

This new concept, however, is different, in that it allows an electric climb past a far smaller portion of the Earth’s gravity well. Topping out at about 12 miles (20 km), the elevator features a commercial space launch runway at the top, where single-stage reusable spacecraft can launch and land in thin atmosphere, and slightly reduced gravity. This would be well matched with other next-gen space technology programs, like several ongoing reusable spacecraft from companies like Lockheed and SpaceX, including those that can do vertical takeoff vertical landing (VTVL) maneuvers.

A “traditional” space elevator concept keeps itself rigid with centrifugal force, since it’s so long and heavy that the rotation of the Earth keeps it taught. At just 12 miles in length, however, this concept doesn’t generate enough outward acceleration to stay straight, and thus the engineers have come up with an alternative: gas pressure. They plan to make their huge cylinder out of kevlar rings stitched together and then blow it up — like the aerospace industry’s version of those inflatable car lot dudes. Thoth wants to fill it with either hydrogen or helium, but it’s not a matter of making the elevator float like a helium balloon — they plan to add enormous pressures of the gas, keeping it rigid through mechanical stress. On the one hand, hydrogen is flammable, on the other helium is expensive…

The elevator will purportedly feature a system of gyroscopes so it can detect large bends and keep itself stable. Cars will likely climb the tube itself, rather than using a cable or ribbon, and the creators are still deciding whether those cars should go on the insider or outside of the tube. The inside would seem to provide a bit of extra safety, and consistent buoyancy through gas pressure, but climbing the outside of the tube would certainly increase the appeal to space tourism.

Amazingly, the company thinks it could begin on a scale version quickly, hoping to finish a prototype at just under a mile in height within five years. They estimate a version could reach the 12-mile mark within a decade, for about $5 billion. That’s just a fraction of what it cost to build the international space station, mostly because this space elevator can be built on the ground and slowly erected higher and higher, rather than having to be built space, then unspooled down to the surface.

A more traditional space elevator design.

Still, I do wonder what the economic argument would be in favor of their 1-mile pilot project; spacecraft would still be subject to the vast majority of the Earth’s gravity, at that height, and thus the scale version might not save enough on launch budgets to justify investment. That’s honestly a potential problem for the full-scale version as well: will a 12-mile launch advantage be enough to offset the cost of construction? Thoth says the full version could cut fuel needs by 30% — will that be good enough to justify billions up front?

Space elevators are a big topic of discussion, which ought to show you how broken the aerospace launch industry is, given how totally hypothetical the devices really are. Places like NASA have a hard time imagining figurative (or literal) moonshot projects when there is such a stark price and difficulty barrier between them and the cosmos they study. The next great space-based mega-project might not be a space elevator, but you can bet it will address this problem somehow.