Timeline for An electromagnetic space elevator?
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| Sep 17, 2012 at 8:18 | comment | added | Ron Maimon | I just noticed your last sentence--- it's not true in any way that this is impossible--- it's very practical in terms of cost for the launch. The result is a space structure that you can go up to by elevator, and then you can build a launchpad for Orion style spaceships that don't make atmospheric fallout, cheap space telescopes, space tourism, and generally, everything a normal space-station does, but not in 0g. You can make a sequence of such structures up to 6000 km up. | |
| Sep 16, 2012 at 7:13 | comment | added | Ron Maimon | Thanks for the answer, I was wrong about the expelling, and I am sorry for going back and forth, but I was embarassed about asking something so half-baked. I did the physics 101 calculation, of course, and it is correct, so +1 to you for saying the obvious, because it is true. | |
| Sep 16, 2012 at 7:01 | comment | added | Ron Maimon | @lurscher: It's not important if it's pinned or not, the force on the current carrying superconductor is IBL as always, as can be seen by conservation laws (for example, consider two wires carrying parallel currents, the conservation laws don't allow the force to change when one becomes superconducting). My comment above is the stupid one, the idea is sound. Whether you expel the field or not, the field stresses give you the same magnetic force regardless. Sorry for the stupidity. | |
| Sep 16, 2012 at 6:52 | comment | added | lurscher | @RonMaimon, a type II superconductor will have flux pinning that will produce lots of torque, but you need quite some current going on | |
| Sep 16, 2012 at 6:45 | comment | added | Ron Maimon | I did this calculation before asking the question, and I noticed the near coincidence, that's why I asked it. The reason to be at the equator is that the magnetic field is strongest there, and it is about double the weight of the superconductor. But the idea doesn't work, the superconductor expels the field. I just screwed up, and didn't notice until later. | |
| Sep 16, 2012 at 6:32 | comment | added | Ron Maimon | Because the formula doesn't work, the superconductor expels the field, there is no significant force. | |
| Sep 16, 2012 at 0:45 | history | answered | Alan Rominger | CC BY-SA 3.0 |