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Designers Ostap Rudakevych and Masayuki Sono have unveiled a design for a skyscraper that would hang from an orbiting asteroid:
Clouds Architecture Office has unveiled plans for a futuristic skyscraper dubbed the "Analemma Tower." The building would hover majestically above the ground because it would be attached -- wait for it -- to an actual asteroid, in space, that is forcibly put into orbit around the earth.
If that's not enough to digest, consider that your exact address in this pendulous pad could be anywhere on Earth. The tower will be suspended via high-strength cabling from an asteroid and placed in "eccentric geosynchronous orbit". In other words, it would be always moving -- residents and visitors would take a daily journey between the northern and southern hemispheres with a prolonged visit over a main "home" point like New York City or Dubai (it's always New York City or Dubai, isn't it?)
[...] Analemma Tower's designer Ostap Rudakevych told CNN that the tower could be made of durable and lightweight materials such as carbon fiber and aluminum. Advances in cable engineering would be needed to achieve the cable strength required to support the structure. Power would come from space based solar panels that have a constant exposure to sunlight. Water for the tower will be captured from clouds and rainwater and maintained in a semi-closed loop system.
As proposed the top of the tower sits at 32,000m and would be expected to reach speeds of 300mph as it travels through the sky.
Elysium 1.0?
(Score: 3, Insightful) by khallow on Thursday March 30 2017, @07:11AM
But the worst thing is the vulnerability of the tether to strikes in orbit, particularly strikes around the center of gravity of the system which by necessity has to pretty far out, about 37,000 km (around the radius of geosynchronous orbit or GSO). For a small space elevator, most of it will burn up in atmosphere aside from a little bit near the anchor point on Earth. But the thicker, more massive tether for this building is much more likely to survive to impact Earth's surface, wrapping around Earth multiple times and imparting the energy equivalent of a good-sized nuclear war in the process. And given the tether system's migration latitude-wise, that's a lot of unpredictability as to what areas would be affected (as in obliterated) compared to a space elevator with a fixed anchor point on Earth.
For example, just consider the building itself. It's 24 km long with an average height of 20 km. Assume that the empty building is a mere one metric ton (Mt) per 10 meters, then you have a mass of 2400 Mt, dropped 20 km. That's roughly half a trillion joules or 100 metric tons of TNT, just by itself. I'll note here that the people in the building will probably be 25-100 per 10 meters as well when fully loaded. That would be by itself, somewhere in the neighborhood of 2 to 8 metric tons per 10 meters which adds another 200 to 800 metric tons of TNT to the mix.
Let's suppose with people, that the total mass of the building is around 20k Mt. This is the low energy part of the problem. Now you need a 37,000 km cable capable of supporting both the mass of the building and more importantly, the mass of the cable. From Wikipedia, we have this [wikipedia.org]:
One plan for construction uses conventional rockets to place a "minimum size" initial seed cable of only 19,800 kg.[2] This first very small ribbon would be adequate to support the first 619 kg climber. The first 207 climbers would carry up and attach more cable to the original, increasing its cross section area and widening the initial ribbon to about 160 mm wide at its widest point. The result would be a 750-ton cable with a lift capacity of 20 tons per climber.
Ignoring that it may not be possible to get a tether material this strong, we're looking at 750 Mt cable to support 20 tons. The mass of the cable is proportional to the desired support mass. So we would need a 750k Mt cable of this material to support a 20,000 Mt building, roughly half of which would be at our cutoff point. The center of gravity of the segment cut off at 37,000 km (the physical tether length would be longer than that since it would trail out to the west as it ascends) would be somewhere around 15,000-20,000 km above Earth and supposed that it's half the mass of the cable. I figure a few megatons just of potential energy would come slamming down on Earth with some considerable additional energy coming from the kinetic energy of the higher part which has near orbital velocity and will wrap around Earth like a yo yo.
So while it's an interesting design experiment, it has huge liabilities from the possibility for global catastrophe that aren't present in normal buildings. If I were to build a 24 km high building, it wouldn't be capable of harming anything directly outside of the local region. No matter how bad the disaster, my building in Dubai isn't going to wipe out Delhi or Hong Kong. But with a massive tether wrapping around Earth multiple times (with movement perpendicular to the equator), it might be possible to nail both even though they aren't at the same latitude.