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Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

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Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#11
post #2

Cooling a 200km loop with liquid helium sounds more than moderately difficult! Neat idea but not particularly possible given current material science as always seems to be the case with space elevators.

What about using Starship or similar to move the coolant up, then let it “fall” down?

Once you have the elevator operated some of the transportation could be used for refueling coolant.

And you start it from space and gradually lower it down to earth.

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#12

(2001). I'm curious what has changed in this space since then.

I believe the test tether someone took up burned itself to a crisp. The magnetic flux it experienced from the earth was much more intense than their math predicted. That’s the last I heard.

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#13
post #2

Cooling a 200km loop with liquid helium sounds more than moderately difficult! Neat idea but not particularly possible given current material science as always seems to be the case with space elevators.

What about using Starship or similar to move the coolant up, then let it “fall” down? Once you have the elevator operated some of the transportation could be used for refueling coolant. And you start it from space and gradually lower it down to earth.

I don't know why you think that would help?

If we could build this at all, we could build it on the ground, then just switch it on (gradually) and it would float, and if we needed to get consumables up, they can be pulled up on a winch like any other payload to space.

But also, I don't know why you think Starship is the right category for a solution; the structure in this paper is 200 kilometers in size (it says altitude, but for magnetic repulsion the best separation distance is a constant factor of the size before your get performance issues), whereas a fully stacked Starship is about 0.12 - 0.15. It would be like trying to refuel a 747 in flight with an personal selfie drone.

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#14
post #2

Cooling a 200km loop with liquid helium sounds more than moderately difficult! Neat idea but not particularly possible given current material science as always seems to be the case with space elevators.

What about using Starship or similar to move the coolant up, then let it “fall” down? Once you have the elevator operated some of the transportation could be used for refueling coolant. And you start it from space and gradually lower it down to earth.

[deleted]

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#15
NbTi has a critical temperature below 10K and generate fields of around 10 T [1]. The paper contemplates a 2T field.

Could CeOFeAs permit cooling with hydrogen [2][3]?

[1] https://en.m.wikipedia.org/wiki/Niobium%E2%80%93titanium

[2] https://www.sciencedirect.com/science/article/abs/pii/S09214...

[3] https://en.m.wikipedia.org/wiki/High-temperature_superconduc...

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#16
I seem to remember reading about this in Popular Science around that time. Of all the things I saw in that magazine, the space elevator made of carbon nanotubes was always the one that stuck with me. Though I seem to remember PopSci taking about harnessing an asteroid, or something, and putting it geosynchronous orbit, as a means to create the top anchor point.

25 years later, it seems just as far fetched.

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#17
post #13

Earlier quoted context omitted.

What about using Starship or similar to move the coolant up, then let it “fall” down? Once you have the elevator operated some of the transportation could be used for refueling coolant. And you start it from space and gradually lower it down to earth.

I don't know why you think that would help? If we could build this at all, we could build it on the ground, then just switch it on (gradually) and it would float, and if we needed to get consumables up, they can be pulled up on a winch like any other payload to space. But also, I don't know why you think Starship is the right category for a solution; the structure in this paper is 200 kilo meters in size (it says alt…

The Starship was only for moving coolant, not as part of the elevator.

I was thinking you probably have to have extra payload to stop the end. And that it then would be better to start from the top, than from bottom

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#18
post #12

(2001). I'm curious what has changed in this space since then.

I believe the test tether someone took up burned itself to a crisp. The magnetic flux it experienced from the earth was much more intense than their math predicted. That’s the last I heard.

Do you have any idea which mission that was?

Wikipedia has a listing, if that helps: https://en.wikipedia.org/wiki/Space_tether_missions>

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#19
post #13

Earlier quoted context omitted.

I don't know why you think that would help? If we could build this at all, we could build it on the ground, then just switch it on (gradually) and it would float, and if we needed to get consumables up, they can be pulled up on a winch like any other payload to space. But also, I don't know why you think Starship is the right category for a solution; the structure in this paper is 200 kilo meters in size (it says alt…

The Starship was only for moving coolant, not as part of the elevator. I was thinking you probably have to have extra payload to stop the end. And that it then would be better to start from the top, than from bottom

I can't visualise what you're trying to suggest. "Stop the end"?

Re: Magnetically levitated space elevator to low-earth orbit (2001) [pdf]

#20
post #12

Earlier quoted context omitted.

I believe the test tether someone took up burned itself to a crisp. The magnetic flux it experienced from the earth was much more intense than their math predicted. That’s the last I heard.

Do you have any idea which mission that was? Wikipedia has a listing, if that helps: https://en.wikipedia.org/wiki/Space_tether_missions >

TSS-1R mission, 1996

"TSS-1R was deployed (over a period of five hours) to 19.7 km (12.2 mi) when the tether broke. The break was attributed to an electrical discharge through a broken place in the insulation."

"Measured currents on the tether far exceeded predictions of previous numerical models by up to a factor of three"

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