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Form of the Earth
Axis and Direction of Rotation
- Looking down at the earth onto the North Pole, it can be seen to spin around its polar axis in an anti-clockwise direction.
- The polar axis passes through two points, the North geographic pole (True North) and the South geographic pole (True South).
Geographic and Magnetic Poles
- The earth acts as a huge magnet, and its lines of magnetic force are sufficiently strong enough to influence the direction of a freely suspended magnetic needle.
- The poles of the magnet earth are known as the North magnetic pole and the South magnetic pole.
- At the present time, the north magnetic pole is in the general area of Hudson's Bay in Canada, and the south magnetic pole is near South Victoria land in Antarctica.
- The lines of magnetic force joining these two poles run roughly north-south.
- The actual direction now shown by the magnet is called magnetic north, and this is the datum used to measure magnetic direction.
- The geographic and magnetic poles are not situated in the same place.
- They are about 1000 miles away from each other.
- The North and South geographic poles are fixed locations which the earth rotates about while the magnetic poles will move in a full circle around the geographic poles roughly every 900 years.
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