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What is a pole?
A geographical pole (also geographic pole) is either of the two points—the north pole and the south pole—on the surface of a rotating planet (or other rotating body) where the axis of rotation (or simply "axis") meets the surface of the body. The north geographic pole of a body lies 90 degrees north of the equator, while the south geographic pole lies 90 degrees south of the equator.
It is possible for geographical poles to "wander" slightly relative to the surface of a body due to perturbations in rotation. The Earth's actual physical North Pole and South Pole vary cyclically by a few meters over the span of each few years. This phenomenon is distinct from the precession of the equinoxes of the Earth, in which the angle of the planet (both axis and surface, moving together) varies slowly over tens of thousands of years.
As cartography requires exact and unchanging coordinates, cartographical poles (also cartographic poles) are fixed points on the Earth or another rotating body at the approximate location of the slightly varying geographical poles. These cartographical poles are the points at which the great circles of longitude intersect.
Geographical poles and cartographical poles should not be confused with magnetic poles, which can also exist on a planet or other body.
For the geographical and cartographical poles on Earth, see:
* North Pole
* South Pole
For geographical and cartographical poles on astronomical bodies other than Earth, see Poles of astronomical bodies.
It is possible for geographical poles to "wander" slightly relative to the surface of a body due to perturbations in rotation. The Earth's actual physical North Pole and South Pole vary cyclically by a few meters over the span of each few years. This phenomenon is distinct from the precession of the equinoxes of the Earth, in which the angle of the planet (both axis and surface, moving together) varies slowly over tens of thousands of years.
As cartography requires exact and unchanging coordinates, cartographical poles (also cartographic poles) are fixed points on the Earth or another rotating body at the approximate location of the slightly varying geographical poles. These cartographical poles are the points at which the great circles of longitude intersect.
Geographical poles and cartographical poles should not be confused with magnetic poles, which can also exist on a planet or other body.
For the geographical and cartographical poles on Earth, see:
* North Pole
* South Pole
For geographical and cartographical poles on astronomical bodies other than Earth, see Poles of astronomical bodies.
