This incredibly cool rings-around-Earth visualization has me dreaming about space elevators and a man-made ring around the Earth.
Now, of course this is a huge undertaking. The counterweight-end of the space elevator would be some 62,000 miles up! The moon is ~240,000 miles from Earth– the space elevator would reach 1/4 the way to the moon!
But imagine if we built several of these space elevators and wanted to connect them in a big ring, encircling the entire earth. At some point up there along the elevators, there will be a place where the downward pull of earth’s gravity matches the upward fling of centrifugal force. For one elevator, that is the “center of mass for system,” as it is called in our cool illustration from Wikipedia. That balance point may be different for a system of buildings placed into a huge ring, but nonetheless, the principle is the same: there will be a point where gravity equals centrifugal force.
Now, imagine if you were at this point up in an elevator car, and you let go of your phone. It should theoretically stay right there, relative to you, as well as relative to the Earth, hovering over the same spot on the earth indefinitely. Ok now, do that same thing, but with a bus, or a building. Same thing, right? It should stay there. Now, attach another building, then another and another and so on, until you’ve encircled the entire earth.
Think how huge this structure would be, how much ROOM it would give us, in a zero-g space station. Let’s do a calculation for if the ring were in geostationary orbit (it would probably be farther out, but we know these numbers)… Geostationary orbit is some 22,000 miles up. Since the radius of the earth is just under 4,000 miles, that’s a circle with radius of 26,000 miles… which means its circumference (its total length) would be 82,000 miles!
That is a LOT of room!
Now, look again at T0R0YD‘s amazing video, and imagine just one sliver-thin ring up there… but with people living inside it, growing their food, living their lives. What kind of life would that be..?