Points on a rotating astronomical body where the axis of rotation intersects the surface
A geographical pole or geographic pole is either of the two points on Earth where its
axis of rotation intersects its surface.[1] The
North Pole lies in the
Arctic Ocean while the
South Pole is in
Antarctica. North and South poles are also defined for other planets or satellites in the
Solar System, with a North pole being on the same side of the
invariable plane as Earth's North pole.[2]
Relative to Earth's surface, the geographic poles move by a few metres over periods of a few years.[3] This is a combination of
Chandler wobble, a free oscillation with a period of about 433 days; an annual motion responding to seasonal movements of air and water masses; and an irregular drift towards the 80th west
meridian.[4] As
cartography requires exact and unchanging coordinates, the averaged[citation needed] locations of geographical poles are taken as fixed cartographic poles and become the points where the body's
great circles of
longitude intersect.
^Kotlyakov, Vladimir; Komarova, Anna (2006).
"pole; geographic pole". Elsevier's dictionary of geography : in English, Russian, French, Spanish and German (1st ed.). Elsevier. p. 557.
ISBN9780080488783. Retrieved 22 June 2015.
^Archinal, B. A.; A’Hearn, M. F.; Bowell, E.; Conrad, A.; Consolmagno, G. J.; Courtin, R.; Fukushima, T.; Hestroffer, D.; Hilton, J. L.; Krasinsky, G. A.; Neumann, G.; Oberst, J.; Seidelmann, P. K.; Stooke, P.; Tholen, D. J.; Thomas, P. C.; Williams, I. P. (February 2011). "Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009". Celestial Mechanics and Dynamical Astronomy. 109 (2): 101–135.
Bibcode:
2011CeMDA.109..101A.
doi:
10.1007/s10569-010-9320-4.
S2CID189842666.
^"Polar motion". International Earth Rotation and Reference Systems Service. Federal Agency for Cartography and Geodesy. 2013. Retrieved 22 October 2020.