Geographical pole

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For other uses, see Pole (disambiguation).

A geographical pole, also known as a geographic pole, is either of the two points on a planet, moon or other relatively large rotating body where the body's axis of rotation meets its surface. As with Earth's North and South Poles, they are usually called that body's "north pole" and "south pole", one lying 90 degrees in one direction from the body's equator and the other lying 90 degrees in the opposite direction from the equator.

Perturbations in a body's rotation mean that geographical poles are prone to "wander" slightly on its surface. Every few years, for instance, the Earth's North and South Poles vary cyclically by a few metres. (This phenomenon is distinct from axial precession, which, in Earth's case, mean the angle of both the its axis and surface, moving together, varies very slowly over tens of thousands of years.) As cartography requires exact and unchanging coordinates, the averaged[citation needed] locations of geographical poles are taken as fixed cartographical poles (cartographic poles) and become the points where the body's great circles of longitude intersect.

If, like the Earth, a body generates a magnetic field, it will also possess magnetic poles. These should not be confused with its geographical or cartographical poles.

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