In answering this question tonight Dawn and I learned about the differences between geographic poles, magnetic poles, geomagnetic poles, eccentric poles, celestial poles, the Pole of Inaccessibility, and the Gallup Poll (ha ha).
Geomagnetic poles gave us the most difficulty. These poles reflect the calculated axes of the magnetosphere. Scientists calculate the position of the geomagnetic poles using the IGRF, a series of mathematical models which reflect magnetic field data collected from around the world.
Magnetic poles reflect the observable spots on the earth's surface where magnetic fields point downwards (the "dip" is 90°).
I still feel some confusion about why the calculated geomagnetic poles do not coincide with the observable magnetic poles. Is it because the equations only produce rough approximations, or is it because the equations assume a perfect dipole model, or something else? How is the magnetosphere different from the earth's magnetic field? Or are they the same?
Links:Magnetic poles reflect the observable spots on the earth's surface where magnetic fields point downwards (the "dip" is 90°).
I still feel some confusion about why the calculated geomagnetic poles do not coincide with the observable magnetic poles. Is it because the equations only produce rough approximations, or is it because the equations assume a perfect dipole model, or something else? How is the magnetosphere different from the earth's magnetic field? Or are they the same?
http://en.wikipedia.org/wiki
http://gsc.nrcan.gc.ca/geomag
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