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Space Elevator

neal.fun

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Re: Space Elevator

#131

Post by p_l »

Metacelsus wrote: post #87
lproven wrote: post #75

Earlier quoted context omitted.

That's odd. The first episode was the only one I watched and I don't remember that bit. It might have grabbed me. A terrorist attack on a space elevator is a pivotal plot point in Blue Mars by Kim Stanley Robinson, which IMHO is a better work in basically every way than Asimov's magnum opus.

Doesn't the space elevator attack happen in Red Mars not Blue Mars?

There's a terrorist attack, sorta, in latter book, but Red Mars was admittedly a legitimate military strike, as was destruction of Phobos.

Re: Space Elevator

#132

Post by dmd »

jve wrote: post #86
anticrymactic wrote: post #79

Earlier quoted context omitted.

PayPal and Apple pay take a significant cut of the transaction. CC is a lot less and bank is mostly free of TX fees. Most users don't know/don't care, so given the option, they will likely take it and funnel their donations to conglomerates.

I don't like to input Cc details into random sites whose main business is processing said transactions.

I'm not understanding this sentiment at all. You'd rather input your CC details into a site whose main business isn't dealing safely with credit cards - rather than inputting it into Stripe (which is what his site uses), whose entire raison d'etre is doing so?

Re: Space Elevator

#133

Post by isgb »

> Space elevators are actually a possible idea being considered by scientists. > The hard part is making a strong enough cable. And finding enough elevator music...

Most engineers would bring up a lot more issues than just finding a strong cable. Also, most attempts with e.g. carbon nanotubes have been abandoned ages ago https://www.newscientist.com/article/2093356-carbon-nanotube....

- We don't have a good ascent mechanism other than rockets - and then we might just use rockets without building an elevator. - We don't have a good (and safe) descent mechanism. - Maintenance? Protection from space debris? Protection from oscillations? Ground-protection if the elevator collapses?

This is dyson-sphere level of fiction. We can do back-of-the-napkin calcualtions on how things would work, but the practicalities make it completely impossible or impractical.

Re: Space Elevator

#135

Post by pbmonster »

Yizahi wrote: post #97
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.

Russia, China, Iran etc. are throwing a hissy fit whenever even a small weapons are deployed in the neighboring countries. USA too if we are being fair. They won't even wait for that opportunity.

I think they mostly throw a fit because medium range ballistic missiles allow practically no useful early warning.

When the ICBMs go up, early warning radars notice them right away and you still have time to act. Leaders can make it to helicopters and basement bunkers, bomber squadrons can scramble, missile silos can already be empty when hit, road mobile ICBM launchers can still relocate.

But with a large enough number of MRBMs, your opponent might get ideas. They might start thinking about getting away with a decapitation strike.

The military space elevator is more like an ICBM in this case. There will be ample warning when somebody drops something from geostationary orbit (and also when somebody drops something from lower up).

Re: Space Elevator

#136

Post by Zobat »

Interesting how counter intuitive it felt to scroll up from the "landing spot". Even with the instructions right there on the screen I tried scrolling down at first.

Re: Space Elevator

#137

Post by blueg3 »

anticrymactic wrote: post #79
daniel_iversen wrote: post #4

This was incredible! Couldn't stop scrolling and reading. For a kid of a certain age and curiosity it'll blow their mind! I'm so grateful the creator made this, shame that his "buy me a coffee" isn't a simple PayPal or Apple Pay but you have to put in credit card or bank details!!

PayPal and Apple pay take a significant cut of the transaction. CC is a lot less and bank is mostly free of TX fees. Most users don't know/don't care, so given the option, they will likely take it and funnel their donations to conglomerates.

PayPal doesn't cost significantly more than what a small online place can get from other payment processors. It's something like 3% + $0.50. That's also not much more than what a small business can usually get for in person credit cards.

This site does use buymeacoffee.com, which appears to be a dedicated payment platform. Its transaction fee is apparently 5%, which is steeper, but better for these small donations because of the lack of a fixed fee.

Re: Space Elevator

#138

Post by kqr »

mr_toad wrote: post #90
icetank wrote: post #77

Earlier quoted context omitted.

The issue of the line falling back to earth is solved by putting the base of the elevator on water. If the top part of the elevator was cut of you could even detonate charges along the line to make sure all pieces fall into water.

A space elevator on Earth would be over 35,000 kilometres long. Depending where it broke it could wrap halfway around the Earth.

At first I was confused by this because the Kármán line is less than a percent of Earth's circumference up, but then I realised we're probably talking a geostationary anchor or something, which is very nearly a circumference up.

Re: Space Elevator

#139

Post by daeken »

arethuza wrote: post #44
243423443 wrote: post #25

Earlier quoted context omitted.

Did you read Seveneves by Neal Stephenson? In the second part of the book, they use this and related technologies.

I think those technologies are mentioned throughout the book - just at a much larger scale in the second part.

Bolos are used for spin gravity in the first part, but that's very different from the rotovators used in the second part. Both in concept and design. The key point with the rotovator is that the tip is moving at ~0m/s relative to the body it's orbiting when it's at its nadir, allowing you to just hop/grab on.

Re: Space Elevator

#140

Post by mrkickling »

isgb wrote: post #133

> Space elevators are actually a possible idea being considered by scientists. > The hard part is making a strong enough cable. And finding enough elevator music... Most engineers would bring up a lot more issues than just finding a strong cable. Also, most attempts with e.g. carbon nanotubes have been abandoned ages ago https://www.newscientist.com/article/2093356-carbon-nanotube... . - We don't have a good ascent m…

You didn't even mention the music!
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