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The South Magnetic Pole is the wandering point on the Earth's Southern Hemisphere where the geomagnetic field lines are directed vertically upwards. It should not be confused with the lesser known South Geomagnetic Pole described later. For historical reasons, the "end" of a magnet that points (roughly) north is itself called the "north pole" of the magnet, and the other end, pointing south, is called the magnet's "south pole". Because opposite poles attract, the Earth's South Magnetic Pole is physically actually a magnetic ''north'' pole (see also ). The South Magnetic Pole is constantly shifting due to changes in the Earth's magnetic field. As of 2005 it was calculated to lie at ,〔(【引用サイトリンク】title=Geomagnetism Frequently Asked Questions )〕 placing it off the coast of Antarctica, between Adelie Land and Wilkes Land. In 2015 it lies at (est).〔(British Geological Survey - Magnetic Poles )〕 That point lies outside the Antarctic Circle. Due to polar drift, the pole is moving northwest by about 10 to 15 kilometers per year. Its current distance from the actual Geographic South Pole is approximately 2860 km.〔 The nearest permanent science station is Dumont d'Urville Station. Wilkes Land contains a large gravitational mass concentration. ==Expeditions== Early unsuccessful attempts to reach the magnetic south pole included those of French explorer Dumont d'Urville (1837–40), American Charles Wilkes (expedition of 1838–42) and Briton James Clark Ross (expedition of 1839–43).〔(''Antarctic Treaty System: an Assessment'', p. 90 ), US National Research Council, 1986〕 The first calculation of the magnetic inclination to locate the magnetic South Pole was made on January 23, 1838 by the hydrographer , a member of the Dumont d'Urville expedition in Antarctica and Oceania on the corvettes "L'Astrolabe" and "Zélée" in 1837-1840, which discovered Adelie Land. On 16 January 1909 three men (Douglas Mawson, Edgeworth David, and Alistair Mackay) from Sir Ernest Shackleton's Nimrod Expedition claimed to have found the South Magnetic Pole, which was at that time located on land. However, there is now some doubt as to whether their location was correct. The approximate position of the pole on 16 January 1909 was .〔Shackleton, Roland Huntford〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「south magnetic pole」の詳細全文を読む スポンサード リンク
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