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Space Elevator

neal.fun

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Re: Space Elevator

#61

Post by dpq »

Amazing work! One minor correction:

> As particles from the sun hit the atmosphere, they excite the atoms in the air. These excited atoms start to glow, creating brilliant displays of light called auroras.

The process is a bit more nuanced than that. The modern mainstream understanding is that the growing pressure of the solar wind makes the tail of the magnetosphere "contract" (sort of pushing it inwards from the sides), which leads to reconnection of magnetic field lines. Once the reconnection occurs, the magnetic field lines that remain bound to the geomagnetic dipole accelerate the particles on them towards the Earth => they slam into the atmosphere, exciting the atoms and generating the aurora.

Re: Space Elevator

#63

Post by pbmonster »

tsimionescu wrote: post #54
pbmonster wrote: post #41

Earlier quoted context omitted.

I don't see it. Why worry about a weaponized space elevator when stealth bombers, cruise missiles and ICBMs exist? If the power building the space elevator wants to bomb you, you're going to get bombed.

The bigger problem I think is the elevator itself. Cutting it and letting it fall would be far more destructive than any weapon ever fired or even conceived.

Probably no easy task.

Snipping off just the first few kilometers is not catastrophically destructive yet, and cutting it down further up would require multistage rocket designs, sophisticated steering/targeting and potentially significant yield (you'd need to cut unobtainium, after all...). If you can build a space elevator, you can defend against those.

You better thoroughly inspect what cargo you put on the elevator itself, of course.

Re: Space Elevator

#64

Post by Jolter »

tsimionescu wrote: post #58
tempestn wrote: post #8

TIL it's estimated that over 48 tons of meteors hit the atmosphere every day. Regarding actual space elevators though, while they're not sci-fi to the extent of something like FTL travel - ie. they're technically not physically impossible - they're still pretty firmly in the realm of sci-fi. We don't have anything close to a cable that could sustain its own weight, let alone that of whatever is being elevated. Plus,…

While a space elevator doesn't contradict any fundamental limits of physics, that doesn't mean it's actually possible to build one. There is no reason to be certain that it's actually possible to create a material that has the required characteristics in terms of tensile strength to support it's own weight, plus the weight of the elevator, plus the weight of all the additional cabling. It also has to endure the huge…

A terrorist attack on a space elevator happens to figure in the first episode of the TV series Foundation.

https://foundation.fandom.com/wiki/Bombing_of_the_Star_Bridg...

It’s about as devastating as you would expect.

Re: Space Elevator

#68

Post by bob1029 »

pbmonster wrote: post #41
Yizahi wrote: post #37

Earlier quoted context omitted.

The problem with space elevator is not only the lack of material today, but also the fact that such elevator is an ultimate and very fragile weapons platform, you basically get stones up the well and then drop them on the enemy. Meaning that any authoritarian country would destroy it even before it is ever built. And sturdy enough space elevator after it's break at any high point would start falling down on the plane…

I don't see it. Why worry about a weaponized space elevator when stealth bombers, cruise missiles and ICBMs exist? If the power building the space elevator wants to bomb you, you're going to get bombed.

And hypersonic weapons. If you can get one to fly at Mach 20 for at least 10 minutes, you could cover the entire surface of the planet with a dozen launchers.
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