Alita, which was not a bad movie, is based off an anime. I hadn't looked at the worldbuilding. Apparently there is some.
What this place offers is an orbital ring, which can use the high-tensile compound of your choice; in Paul Birch's day that was just kevlar. We've been talking about that here for years. Nah: the fun part is how to get from the ring into space. Because the ring orbits. It is a moving platform.
So here on 4chan (sorry) is a hopefully-fair-use screencap (jpg). Tiphares is 3 km above... the equator, I assume; so hop on over from the Andes bro. Keep in mind that Tiphares is hanging from the magnetic field generated from the ring, not attached to its orbiting components.
You then take the lift to the sky hook - that is, to the ring - for 600 km, a reasonable LEO without too much exosphere interference. 120 km/hour would take five hours which is a little boring but no problem for a Texan driver. Personally I'd ponder more that 600 km is thermopause; Skylab at 440ish km died because our atmo had an unscheduled bump out there. There's 2000 km to play with before the Van Allens start messing with the superconductors from the upper side.
Anyway Jeru seems to be on Tiphares. I'd be reluctant to host a full city there; tensile strength will be an engineering nightmare. And its mass will drag the orbital ring.
The fun really starts above the ring. Ketheres is out at, yes, 1200 km. Best I can tell Ketheres is not in its own orbit, but also hanging from the ring... aaaand here the diagram makes less sense. "Centrifugal force" is keeping Ketheres in its higher state: so, Ketheres is physically tethered, to the moving parts of the ring, therefore should not line up with the levitating lower cord... excepting when the orbit allows. The diagram must assume timetables so that anyone wanting a direct Tiphares-Ketheres trip can have one. That's fine with me. Less fine with me: shouldn't Ketheres be trailing diagonally...?
Ketheres further hosts the city Jeru. Wild. I wonder if this force is enough to keep a pseudogravity on the space-facing side. Again: tensile, and dragging the orbit of the ring.
I am despite-this liking that this spinning cable is not a GEO-to-Earth solution, with "nanocarbon" handwavium. Because those don't exist and probably never will.
All this will be much easier if above thermopause and using adequate radiators. In fact the temperature-differential between earth and space is a major source of energy for Tiphares. So not only would the ring be keeping sunlight off of Earth but what warmth is left on Earth is being radiated to space. Brrr!
Next question: we can't drop a cable from GEO right to Earth's atmo. But can we drop one just as far as Ketheres?
No comments:
Post a Comment