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Space Elevator

neal.fun

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Re: Space Elevator

#11

Post by sebzim4500 »

avmich wrote: post #5

I don't understand why so many seemingly educated people keep discussing Earth space elevator. For a long time there is a conclusion that the elevator is incompatible with Earth satellites, which mostly fly below GEO, and elevator will collide with satellites, with all negative consequences. The inherent elevator problem has nothing to do with the material of the cable. Am I missing something?

As satellite density increases every satellite will need a collision avoidance system anyway. And getting from geo to leo is way less difficult than launching to leo from the ground.

Re: Space Elevator

#13

Post by gibolt »

A key point with space elevators is that they aren't limited to Earth. The solar system has plenty of celestial bodies that could benefit (us) from having one.

It may not be as significant as the impact of an Earth-based one, but any propellant savings is a win.

Re: Space Elevator

#14

Post by philwelch »

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.

Yeah, I wish this went on as far as an actual space elevator would, perhaps with extra visualizations of the heights of various orbits. The top would be slightly above geostationary orbit, since you would need the center of mass to be at the geostationary point in order to work.

Re: Space Elevator

#15

Post by wonrax »

paxys wrote: post #6

Amazing visualization. The most interesting part to me is the weird fluctuation in temperature. You'd think it would trend in a single direction. What causes all the frequent ups and downs?

At 17446m mark:

> Unlike the troposphere, the temperature in the stratosphere increases the higher you go.

Re: Space Elevator

#16

Post by philwelch »

gibolt wrote: post #13

A key point with space elevators is that they aren't limited to Earth. The solar system has plenty of celestial bodies that could benefit (us) from having one. It may not be as significant as the impact of an Earth-based one, but any propellant savings is a win.

Some of those celestial bodies are even small enough that we could build the elevators with existing materials, too.

Re: Space Elevator

#18

Post by mcv »

I thought it would go all the way up to the anchor of the space elevator, so I expected to have to scroll up for another couple of hours. I guess the creator wisely decided that was a bit too much.

Amazing how high the F-104 Starfighter could fly, by the way.

Re: Space Elevator

#19

Post by mcv »

philwelch wrote: post #16
gibolt wrote: post #13

A key point with space elevators is that they aren't limited to Earth. The solar system has plenty of celestial bodies that could benefit (us) from having one. It may not be as significant as the impact of an Earth-based one, but any propellant savings is a win.

Some of those celestial bodies are even small enough that we could build the elevators with existing materials, too.

A space elevator on Mars is probably totally feasible. But of course the benefits would be much larger on Earth.

The problem is: the benefit of a space elevator is bigger the deeper your gravity well is, but it's also much harder to impossible to make one there.

But I've also been wondering: wouldn't it be possible to have a tapering space elevator? Reduce the weight by making the parts that have to carry less weight thinner?

Re: Space Elevator

#20

Post by mcv »

rasengan wrote: post #3

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

Would be cool, but as far as I understand, even long, continuous carbon nanotubes wouldn't be strong enough to carry their own weight.
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