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Space Elevator

neal.fun

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Re: Space Elevator

#41

Post by hammyhavoc »

hanselot wrote: post #27

I love this. Reminds me of a thread I perused once re Orbital Ring Space elevator concept, and how it seems not only possible, but almost disgustingly cheap (in terms of the gains) with current technology. Not only would such an endeavor restore some aspect of pride to humanity, but the benefits are quite numerous. To name a few low-hanging fruit: The research done to make it possible, would definitely advance severa…

And so what about the downsides? The ultimate target for terrorists. If that comes down and it wraps itself around the Earth, it'll be devastating.

Re: Space Elevator

#42

Post by amelius »

rasengan wrote: post #3

I love this. Space elevators are going to be here much sooner than it seems with carbon nanotube tech. :)

Too bad someone will write an article titled "Will we get space elevators sooner than we think?" and Betteridge's law will prevent it from happening.

Re: Space Elevator

#43

Post by once_inc »

virtualritz wrote: post #35

This is great. I just wish there was one way to switch all units. The temp. can be switched between F/C by tapping on it. The height is metric and seems fixed and then stuff in text bubbles is again imperial (e.g. mph instead of kph).

That is mostly because the international space community works with metric, so the Karman line is at 100km above earth, and converting to imperial units would be forced.

Remember, there are only three countries that use imperial units; two third-world counties, and a global superpower.

Re: Space Elevator

#46

Post by falcor84 »

hammyhavoc wrote: post #41
hanselot wrote: post #27

I love this. Reminds me of a thread I perused once re Orbital Ring Space elevator concept, and how it seems not only possible, but almost disgustingly cheap (in terms of the gains) with current technology. Not only would such an endeavor restore some aspect of pride to humanity, but the benefits are quite numerous. To name a few low-hanging fruit: The research done to make it possible, would definitely advance severa…

And so what about the downsides? The ultimate target for terrorists. If that comes down and it wraps itself around the Earth, it'll be devastating.

My understanding is that it would be under tension and orbiting at beyond escape velocity, such that if it got cut off, it would fly away from Earth. Still bad, but not catastrophically. Maybe we could even recover it.

Re: Space Elevator

#47

Post by LeanderK »

davidhyde wrote: post #2

At 74km/h you would reach space (100km karman line) in an hour and a half but you would need to keep going for another 20 days at that speed reach geostationary orbit in order to not fall back to earth when you exit the space elevator.

but do you need to reach geostationary? couldn't you just switch to a rocket at this stage? Maybe a small one to bridge the gap? I would have thought that the first kilometres are the ones where you have to invest the most work so if you just bridge them using the space elevator it would be still an improvement.

Maybe for cargo the 20 days are not really important

Re: Space Elevator

#48

Post by Balero »

hammyhavoc wrote: post #41
hanselot wrote: post #27

I love this. Reminds me of a thread I perused once re Orbital Ring Space elevator concept, and how it seems not only possible, but almost disgustingly cheap (in terms of the gains) with current technology. Not only would such an endeavor restore some aspect of pride to humanity, but the benefits are quite numerous. To name a few low-hanging fruit: The research done to make it possible, would definitely advance severa…

And so what about the downsides? The ultimate target for terrorists. If that comes down and it wraps itself around the Earth, it'll be devastating.

The structure wouldn't be able to passively stay together. If it was to be destroyed then it would burn up in the atmosphere like anything else. It is not made of a magic non-existent material that is infinitely strong. Of course if you had a massive dense asteroid attached that would not, so it makes sense to be careful with what is around it. But the orbital ring itself would break up and be no more dangerous than a bunch of satellites of similar mass.

Also it would not be an "Ultimate target" for "terrorists". Terrorists are violent political activists, not super villains that want to destroy the world. I doubt, for example, that the new-IRA would get a united Ireland by destroying orbital infrastructure.

Re: Space Elevator

#50

Post by hammyhavoc »

Balero wrote: post #48
hammyhavoc wrote: post #41

Earlier quoted context omitted.

And so what about the downsides? The ultimate target for terrorists. If that comes down and it wraps itself around the Earth, it'll be devastating.

The structure wouldn't be able to passively stay together. If it was to be destroyed then it would burn up in the atmosphere like anything else. It is not made of a magic non-existent material that is infinitely strong. Of course if you had a massive dense asteroid attached that would not, so it makes sense to be careful with what is around it. But the orbital ring itself would break up and be no more dangerous than…

I'm more concerned about what's already within our atmosphere and isn't going to burn up. That's a lot of kinetic energy, and nobody says it's going to destroy the Earth, I said it would be devastating.

You're forgetting religious extremists and countless suicide bombers.

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