Wouldn’t jumping off the top of a space elevator just put you in orbit? Or, if by top you mean the point where the space elevator anchors to its counterweight, in orbit around the sun.
OK, you’ve got space elevators wrong, and that’s OK.
The counter-weight doesn’t orbit the sun. It orbits earth. If it orbited the sun it’d rip the thing apart. It sits somewhere above a geostationary orbit, as a geostationary orbit is where the orbit point is always over the same point on the ground, which would be where your elevator is tethered.
The station part is somewhere below this. The higher it is the heavier or further out your counter-weight needs to be —and since it’s already impossible around earth no matter what, this needs to be as low as possible.
Because of this setup, your velocity (while below the geostationary line) is always less than the orbital velocity at that altitude. For example, the ISS orbits the earth 15.5 times a day. Our point on the space elevator cable stays at the exact same position over the ground, so it orbits 0 times. At the same altitude as the ISS you need to be moving the same speed as the ISS or you’ll fall down. It only doesn’t while attached to the cable because it’s being pulled by the counter-weight.
Basically, stuff dropped off a space elevator falls, unless it’s at geostationary altitude. It needs to be given some extra horizontal speed to stay in orbit.
The counterweight orbits above escape velocity, pulling the space elevator’s cable taut. If the cable were severed the counterweight would drift off into space into a solar orbit. So if you jump off at the counterweight, you’ll enter solar orbit.
At geostationary orbit (which could be considered the “top” of the space elevator as that’s where you would normally get off, presumably) the space elevator orbits at exactly orbital velocity, so if you jump off there you end up in orbit. Below that your velocity would be below orbital velocity and you’d fall back to Earth.
Well, the “top” of the elevator could be anywhere. That’s why I said it needs to be as low as possible, because it’s already physically impossible for Earth. The lower and lighter the station is, the less impossible it is, though it’s impossible even with no station and just a cable.
Above geostationary orbit isn’t suddenly in solar orbit though. It’s still got quite a ways to go. It could be at escape velocity, but that’s not necessary.
This is all impossible on Earth anyway though, so if you’re making a story where this is taking place it could be any of these outcomes you want. Whatever works best for the story.
It’s not “physically impossible” on Earth. The forces involved are great, sure, which means you can’t build it out of any present-day material like steel, but they’re not so great that constructing a space elevator would be physically impossible using non-exotic matter like it would be on, say, the Sun, or possibly even just Jupiter. We already know of materials that could be used to make a space elevator cable on Earth if they were available in sufficient quantities – namely carbon nanotubes.
The “top” can’t be anywhere, because not everywhere along the length of the elevator will put released objects in orbit. Turns out on Earth, an object released off of the elevator would reach a stable (but very eccentric) orbit 2/3rds of the way to geostationary orbit – below that, it would fall back to Earth. Conversely escape velocity would be reached at about 53000 km, which is past geostationary orbit but much closer than where the counterweight would be (in most designs?). Objects above escape velocity will by definition escape Earth’s orbit, which most of the time means ending up in a solar orbit.
No, it’s physically impossible. Even the most advanced material possible couldn’t hold the strain that would be required for Earth. Technically it’s right on the limit, but that’s ignoring that we have an atmosphere that’s going to exert forces on it too. On Luna it might make sense.
The top can be anywhere. It would just require adding force to it at/after release. That’s trivial. We already know how to make rockets, or it could be something that pushes or throws it. Compared to building a space elevator, speeding something up is easy.
No, it’s not physically impossible. For an explanation see my previous comment.
I find it funny that you started this conversation by telling me that I’ve “got space elevators wrong” and then proceeded to spout strange and verifiably false nonsense like this on multiple different points.
It’s impossible. You didn’t “explain” anything. It’s on the very edge of being physically possible in a perfect vacuum. That’s it. Consider how a hurricane effects a building. The building requires a ton of extra infrastructure/strength to keep it from breaking. Even the most exotic material possible it’s still on the very edge of technically possible, that if you add any extra overhead to protect from the environment it isn’t possible. Then there’s also satellites and space trash which will be hitting the cable. It’s not a thing that can work on Earth.
then proceeded to spout strange and verifiably false nonsense like this on multiple different points.
Sure… How do you deal with wind on a space elevator? I’m making strange and varifiably false nonsense? You’re repeating pop-sci stuff as if it’s real, without considering how it’d actually need to be to exist. We can barely build buildings that withstand storms. How is a thin cable going to? Carbon nanotubes are only good for tensile strength (resistance to tension). Shear strength is significantly lower, which is what would be required to withstand forces like weather or impacts. Even assuming it’s possible to make the cable, it wouldn’t work because of this.
I don’t care how many pop-sci articles or YouTube speculation videos have been made saying it’s totally possible and just around the corner. They ignore the reality and only discuss the absolute minimum vacuum requirements. It makes a much more appealing article/video to say it’s actually possible than to point out that, in reality, it isn’t because there’s a lot of additional things that were ignored.
Space elevators aren’t “pop-sci”. There’s a plenty of real research that says that one is possible. That is not to say one is going to be built any time soon (though it’s not as implausible within a century or two as one might think), but it is to say that one is not physically impossible; physics very clearly says that it’s possible. Not “on the very edge of being physically possible”. Possible, period. The margins are more than realistic.
The people who did that research weren’t idiots and did in fact account for everything you brought up rather than just assuming a perfect vacuum and spherical cows.
Sure… How do you deal with wind on a space elevator?
By maneuvering the base station to avoid high wind weather systems. Though the effect of wind on the cable would not actually be anywhere near as great as you make it out to be.
We can barely build buildings that withstand storms.
Oh, really? When’s the last time a skyscraper fell due to wind?
Then there’s also satellites and space trash which will be hitting the cable. It’s not a thing that can work on Earth.
The cable can maneuver to avoid trash and satellites, and satellites can maneuver to avoid the cable. Shielding can be applied to protect it from micrometeoroid impacts.
This video talks about some of the issues realistically, though it’s mostly focused on math. It mostly is in the position of “if it were possible, why would we even want it” though, not is it actually possible:
“Why would we even want it” is such a colossally idiotic question that it could only have been uttered by a regressive leftist who’s so brain broken by their Elon Musk hateboner that they literally become the guy in the below image, and lo and behold that’s exactly what I found by clicking open the video. “Uhhhh we don’t need more satellites in space actually because uhhh we have problems down here right now? And uhh billionaire tourism le bad.”
I am so fucking sick of terminally status quo brained people like this who view everything through a lens of present-day American politics and are as a result completely unable to envision a better world.
Wouldn’t jumping off the top of a space elevator just put you in orbit? Or, if by top you mean the point where the space elevator anchors to its counterweight, in orbit around the sun.
OK, you’ve got space elevators wrong, and that’s OK.
The counter-weight doesn’t orbit the sun. It orbits earth. If it orbited the sun it’d rip the thing apart. It sits somewhere above a geostationary orbit, as a geostationary orbit is where the orbit point is always over the same point on the ground, which would be where your elevator is tethered.
The station part is somewhere below this. The higher it is the heavier or further out your counter-weight needs to be —and since it’s already impossible around earth no matter what, this needs to be as low as possible.
Because of this setup, your velocity (while below the geostationary line) is always less than the orbital velocity at that altitude. For example, the ISS orbits the earth 15.5 times a day. Our point on the space elevator cable stays at the exact same position over the ground, so it orbits 0 times. At the same altitude as the ISS you need to be moving the same speed as the ISS or you’ll fall down. It only doesn’t while attached to the cable because it’s being pulled by the counter-weight.
Basically, stuff dropped off a space elevator falls, unless it’s at geostationary altitude. It needs to be given some extra horizontal speed to stay in orbit.
The counterweight orbits above escape velocity, pulling the space elevator’s cable taut. If the cable were severed the counterweight would drift off into space into a solar orbit. So if you jump off at the counterweight, you’ll enter solar orbit.
At geostationary orbit (which could be considered the “top” of the space elevator as that’s where you would normally get off, presumably) the space elevator orbits at exactly orbital velocity, so if you jump off there you end up in orbit. Below that your velocity would be below orbital velocity and you’d fall back to Earth.
Well, the “top” of the elevator could be anywhere. That’s why I said it needs to be as low as possible, because it’s already physically impossible for Earth. The lower and lighter the station is, the less impossible it is, though it’s impossible even with no station and just a cable.
Above geostationary orbit isn’t suddenly in solar orbit though. It’s still got quite a ways to go. It could be at escape velocity, but that’s not necessary.
This is all impossible on Earth anyway though, so if you’re making a story where this is taking place it could be any of these outcomes you want. Whatever works best for the story.
It’s not “physically impossible” on Earth. The forces involved are great, sure, which means you can’t build it out of any present-day material like steel, but they’re not so great that constructing a space elevator would be physically impossible using non-exotic matter like it would be on, say, the Sun, or possibly even just Jupiter. We already know of materials that could be used to make a space elevator cable on Earth if they were available in sufficient quantities – namely carbon nanotubes.
The “top” can’t be anywhere, because not everywhere along the length of the elevator will put released objects in orbit. Turns out on Earth, an object released off of the elevator would reach a stable (but very eccentric) orbit 2/3rds of the way to geostationary orbit – below that, it would fall back to Earth. Conversely escape velocity would be reached at about 53000 km, which is past geostationary orbit but much closer than where the counterweight would be (in most designs?). Objects above escape velocity will by definition escape Earth’s orbit, which most of the time means ending up in a solar orbit.
No, it’s physically impossible. Even the most advanced material possible couldn’t hold the strain that would be required for Earth. Technically it’s right on the limit, but that’s ignoring that we have an atmosphere that’s going to exert forces on it too. On Luna it might make sense.
The top can be anywhere. It would just require adding force to it at/after release. That’s trivial. We already know how to make rockets, or it could be something that pushes or throws it. Compared to building a space elevator, speeding something up is easy.
No, it’s not physically impossible. For an explanation see my previous comment.
I find it funny that you started this conversation by telling me that I’ve “got space elevators wrong” and then proceeded to spout strange and verifiably false nonsense like this on multiple different points.
It’s impossible. You didn’t “explain” anything. It’s on the very edge of being physically possible in a perfect vacuum. That’s it. Consider how a hurricane effects a building. The building requires a ton of extra infrastructure/strength to keep it from breaking. Even the most exotic material possible it’s still on the very edge of technically possible, that if you add any extra overhead to protect from the environment it isn’t possible. Then there’s also satellites and space trash which will be hitting the cable. It’s not a thing that can work on Earth.
Sure… How do you deal with wind on a space elevator? I’m making strange and varifiably false nonsense? You’re repeating pop-sci stuff as if it’s real, without considering how it’d actually need to be to exist. We can barely build buildings that withstand storms. How is a thin cable going to? Carbon nanotubes are only good for tensile strength (resistance to tension). Shear strength is significantly lower, which is what would be required to withstand forces like weather or impacts. Even assuming it’s possible to make the cable, it wouldn’t work because of this.
I don’t care how many pop-sci articles or YouTube speculation videos have been made saying it’s totally possible and just around the corner. They ignore the reality and only discuss the absolute minimum vacuum requirements. It makes a much more appealing article/video to say it’s actually possible than to point out that, in reality, it isn’t because there’s a lot of additional things that were ignored.
This video talks about some of the issues realistically, though it’s mostly focused on math. It mostly is in the position of “if it were possible, why would we even want it” though, not is it actually possible: https://youtube.com/watch?v=Z5aHMB4Tje4&pp=ygUcYXJlIHNwYWNlIGVsZXZhdG9ycyBwb3NzaWJsZQ%3D%3D
Space elevators aren’t “pop-sci”. There’s a plenty of real research that says that one is possible. That is not to say one is going to be built any time soon (though it’s not as implausible within a century or two as one might think), but it is to say that one is not physically impossible; physics very clearly says that it’s possible. Not “on the very edge of being physically possible”. Possible, period. The margins are more than realistic.
The people who did that research weren’t idiots and did in fact account for everything you brought up rather than just assuming a perfect vacuum and spherical cows.
By maneuvering the base station to avoid high wind weather systems. Though the effect of wind on the cable would not actually be anywhere near as great as you make it out to be.
Oh, really? When’s the last time a skyscraper fell due to wind?
The cable can maneuver to avoid trash and satellites, and satellites can maneuver to avoid the cable. Shielding can be applied to protect it from micrometeoroid impacts.
“Why would we even want it” is such a colossally idiotic question that it could only have been uttered by a regressive leftist who’s so brain broken by their Elon Musk hateboner that they literally become the guy in the below image, and lo and behold that’s exactly what I found by clicking open the video. “Uhhhh we don’t need more satellites in space actually because uhhh we have problems down here right now? And uhh billionaire tourism le bad.”
I am so fucking sick of terminally status quo brained people like this who view everything through a lens of present-day American politics and are as a result completely unable to envision a better world.