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Electromagnetic Pole Correction

Stop all this magnetic pole wandering nonsense
 
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The Earth's magnetic field has been tremendously useful over the years. A nice aligned field pointing to fixed points at the top and bottom of the globe is very attractive to navigation enthusiasts. Once Harrison knocked together a reasonable clock, figuring out where you were was possible even in uncivilized regions*.

As it turns out, the magnetic field isn't the reliable old workhorse we assumed it to be. Instead, it wanders about like it doesn't have a job. Clearly, it needs boundaries.

The magnetic field strength of the Earth is weak. 50 micro Tesla at the surface. Instead of furiously issuing navigational corrections, we can simply turn the Earth into an electromagnet. 50 microTesla will need about 100 million Amps, which suggests about 1.5m^2 superconducting cable running a couple of loops around the equator. Once the current is flowing, we won't need to worry about anything apart from cooling the cable and barnacle accumulation, probably.

Careful choice of cable orientation will fix the Earth's magnetic field right through True North where it's supposed to be. No corrections no messing about.

Solar storm protection and aurora light shows are delightful features that nations may draw mutual benefit from, on the understanding that payments are prompt, sudden discontinuation of the service may cause distress.

*There are many subtle techniques used in navigating uncivilized regions of the planet. Often these are specific to the location, which is tricky if you don't know which location you're in. Some say that location is easily derived from a synthesis of environmental cues, but what if you can't see them because there's a great big French signpost in the way?

bs0u0155, Mar 07 2019

Movable London https://www.mortale...mortal-engines.html
[bs0u0155, Mar 11 2019]

[link]






       //1.5m^2 superconducting cable// I thought the point of a superconducting cable was that it was superconducting? In which case, why does it need to be so fat? And how would barnacles adversely affect its performance?
MaxwellBuchanan, Mar 07 2019
  

       //why does it need to be so fat?//   

       Not my subject, but there's a limit to the current density apparently.
bs0u0155, Mar 07 2019
  

       Actually, there might be a cheaper way to do this. A much thinner non-superconducting wire could be pumped with a few billion amps. It would vaporise in the blink of an eye, but the resulting plasma ought to sustain conduction for at least a few microseconds. During that time, the magnetic field ought to be sufficient to magnetize any magnetizeable minerals, so we'd be good to go until tectonics messed it all up again.
MaxwellBuchanan, Mar 07 2019
  

       Also, we ought to pilot this scheme on Mars. Giving it a magnetosphere again ought to mean we can pour some atmosphere on it, without having it solar-winded away. I suppose the only downside would be that eventually Mars and Earth would end up stuck together.
MaxwellBuchanan, Mar 07 2019
  

       //tectonics messed it all up again//   

       Well, that's something else that needs solving. I'm fine with India having a long crash into asia, but we have to maintain standards. Greenwich stays where it is.   

       //pilot this scheme on Mars.//   

       Smaller and the cooling is almost pre-solved.
bs0u0155, Mar 07 2019
  

       //Greenwich stays where it is.// That's an administrative matter. When Greenwhich is several thousand miles north- east of its present location, the North and South poles and all the longitude lines will just have to be shifted. Of course, there's always subduction to worry about but, once again, we can simply redefine all surface features to be mountains.
MaxwellBuchanan, Mar 07 2019
  

       Nice, just what humanity needs, a great leap towards the invariable.
wjt, Mar 08 2019
  

       Give my regards to Gibraltar, [Ian]. As far as I could tell from when I was last there, it's basically the UK but in 1977. Mind you, that was back in 2016.
MaxwellBuchanan, Mar 08 2019
  

       The natural location for the EM north pole would of course be Warsaw.
RayfordSteele, Mar 11 2019
  

       // //Greenwich stays where it is.// That's an administrative matter. //   

       Cut round Greenwich. Jack it up and slide some rollers underneath. Then just move it until it has the correct position relative to the pole.   

       Job done.
8th of 7, Mar 11 2019
  

       //Jack it up and slide some rollers underneath. //   

       They did it in a crappy movie <link>
bs0u0155, Mar 11 2019
  

       Apparently the books were much better, but not known outside of Australia, so maybe they didn't think it was worth it to make a good movie for North American audiences?
notexactly, Mar 11 2019
  

       //didn't think it was worth it to make a good movie for North American audiences?//   

       There's plenty of good movies made for the American audience. I think one reason for the recent downturn in movie quality is that movies are being made for appeal in markets outside America. To make movies appeal to S.E. asia, AND the Indian subcontinent AND Europe/USA, you have to cut out anything that relies on specific locations, particular people or events. It's better if there's no dialog, and sadly, evidence of thought.
bs0u0155, Mar 11 2019
  
      
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