Have you ever wondered just how tall we could build something? Whilst we’ve had modern skyscrapers for almost 2 centuries now advances in material science and building construction techniques means that the helm of the tallest building never lasts for long. The Burj Khalifa currently stands as the world’s tallest structure with it’s tip tickling 830m tall. That’s pretty impressive but it definitely makes you wonder just how far we could push it, which this video explores in depth:
He hits on some good points and of course the tallest structure ends up being a space elevator. I’ve written about them in the past hitting on some of the same issues that the video mentions but interestingly there’s actually a couple other potential structures that could achieve great heights without having to go to the extremes of the space elevator. They’re still not your traditional building however, but they’re quite fascinating in their own right.
One such structure is called a Space Fountain. Instead of relying on a rigid structure like a normal building or tensile strength like in the space elevator the space fountain instead relies on a stream of particles shot through it at high speed to keep itself erect. Such a system need not be set at a geostationary point nor does the orbital end have to stretch all the way past geosynchronous orbit for it to be able to work. Of course the main issue with it is the high energy requirement and the rather catastrophic consequences should the particle containment system fail. Still it’s quite a novel idea, even if it will likely never see the light of day.
Another idea that’s similar to the space fountain is the Orbital Ring concept. In essence you’d wrap the earth with a giant steel cable which would then be accelerated to slightly above orbital speed. Then you’d dangle tethers from it back down to earth, much like you would do with a space elevator. The really cool thing about this kind of structure is that you could also place such stations in geosynchronous orbit by causing the ring to precess around the earth. This could be used quite effectively to make things like GPS and satellite communications better due to the reduced distance. Again its somewhat fanciful due to the high capital cost of setting it up (getting 18,000 tonnes into orbit ain’t cheap) but it is another clever way of building something tall that doesn’t go the full space elevator route.