The magnetic north pole is slowly moving across the Arctic regions of Canada, which constantly monitors it because it is so important to know the location for navigation purposes.
The earth is indeed a giant magnet, as was first theorized in 1600, but the magnetic pole, where all the lines of force of earth's magnetic field come together, does not coincide with the geographic north pole, the north end of the axis on which the earth is spinning. A sailor's magnetic compass is aligned with the magnetic field of the earth so that it can be said to ``point to'' the magnetic pole, not the direction of true north.
Therefore, to be sure where they are, navigators need to know how big the angle is between true north and magnetic north at any point on a map. The angle is called magnetic declination.
Canada takes a magnetic survey every five years and puts the results on maps. In the 1994 survey, the magnetic north pole was on the Noice Peninsula of southwest Ellef Ringnes Island, at 78.3 degrees north, 104 degrees west.
The magnetic pole is now moving in a generally northwestern direction, traveling about 9.3 miles (15 kilometers), every year; in the last 150 years it has moved almost 500 miles (800 kilometers). Furthermore, it moves on any given day in a roughly elliptical path around its average position, and may be as far as 50 miles (80 kilometers) from this average.
The two kinds of magnetic polar motion have different reasons. The northwest motion comes because the shape of the magnetic field of the earth is affected by the motion of the hot, liquid outer core of the earth. The electric currents the core produces are constantly changing, and so is the general location of the pole.
The daily motion comes about because of the stream of charged particles from the Sun, which encounter the earth's magnetic field and cause the production of electric currents in the upper atmosphere. The unstable electric currents jostle the earth's magnetic field and temporarily move the pole on a day-to-day basis. The general northwest motion continues.
2007-10-06 01:04:24
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answer #1
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answered by orchidams 2
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Well technically it changes all the time. In the past 20 years it has moved something like 200 miles. The magnetic poles reverse about every 800,000 years. So sometime in our future, the magnetic north you know...will be right in Antarctica.
2007-10-05 14:28:46
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answer #2
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answered by Star274009 4
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Near Prince of Wales Island, Northwest Territories, Canada.
2007-10-05 11:47:26
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answer #3
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answered by Amphibolite 7
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