- One of two regions of the Earth with very high magnetic field strength, taken to be the points at which a line, drawn between the poles of an idealized magnetic dipole generating the Earth's magnetic field and extending out in both directions, would cross the earth's surface. The north pole of a magnet, such as a compass needle, is attracted to the geomagnetic north pole because the Earth's north pole is actually a magnetic south pole (and its geomagnetic south pole is a magnetic north pole). Magnetic reversals over the course of the Earth's history have switched the polarities of the geomagnetic poles many times. The geomagnetic poles are close to the geographical North and South poles, and to the Earth's magnetic poles. See also magnetic pole.
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