The Earth is a magnet. Scientists do not fully understand why, but they think the movement of molten metal in the Earth’s outer core generates electric currents. The currents create a magnetic field with invisible lines of force flowing between the Earth’s magnetic polesbig ring magnet.
The geomagnetic poles are not the same as the North & South Poles. Earth’s magnetic poles often move, due to activity far beneath the Earth’s surface. The shifting locations of the geomagnetic poles are recorded in rocks that form when molten material called magma wells upn35 magnet through the Earth’s crust & pours out as lava. As lava cools & becomes solid rock, strongly magnetic particles within the rock become magnetized by the Earth’s magnetic field. The particles line up along the lines of force in the Earth’s field. In this way, rocks lock in a recorddiscount neodymium magnets of the position of the Earth’s geomagnetic poles at that time.
Strangely, small neodymium magnets for salethe magnetic records of rocks formed at the same time seem to point to cylindrical magnets for saledifferent locations for the poles. According to the theory of plate tectonics, little cube magnetsthe rocky plates that make up the Earth’s hard shell are constantly moving. Thus, the plates on which the rocks solidified have moved since the rocks recorded the position of the geomagnetic poles. These magnetic records also show that the geomagnetic poles have reversed—changed into the opposite kind of pole—hundreds of times since the Earth formed.
Earth’s magnetic field does not move quickly or reverse often. Therefore, it can be a useful tool for helping people find their way around. For hundreds of years, people have used magnetic compasses to navigate using Earth’s magnetic field. The magnetic needle of a compass lines up with Earth’s magnetic poles. The north end of a Magnet for sale points toward the magnetic north pole.