Why are the magnetic poles of the Earth moving?

2000/06/28 Elhuyar Zientzia

• Geologia

The Earth has two magnetic poles: One is the magnetic south pole and the other is the magnetic north pole, but these magnetic poles do not have to match the geographical ones.

For example, the magnetic north pole does not match the geographic north pole. The geographic north pole is always in the same place, that is, in the Arctic, but not in the magnetic north pole. In fact, the magnetic north pole is in constant movement. It is estimated that since 1948 they have moved 10 km a year, always in the north direction. This measure, however, is the average, since, as has been said, the magnetic north pole moves daily, always performing an elliptical route. Due to this daily movement, the magnetic north pole can be 80 km from its average position.

But we have not yet answered the question why it moves. Let's say that the Earth contains in its core large amounts of iron and nickel that are melting and moving, which generates a very solid magnetic field. This magnetic field is so robust that it also affects objects located tens of thousands of km away. And if it affects space, more on Earth itself. All objects with magnetic properties are oriented with respect to the magnetic field created on Earth, and if the magnetic field moves, the orientation of the objects changes to the same extent.

Therefore, the magnetic poles North and South do not have a fixed position.