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I'm slightly confused about the "north-seeking" pole of a magnet: does it point towards magnetic north, or is it towards geographic north?

I ask because I've been finding different explanations in different places.

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It's unlikely that you found anything that says that magnets point towards geographic north. –  Mark Eichenlaub Jan 20 '13 at 6:04

2 Answers 2

The north-seeking pole always points toward magnetic north, assuming it is only feeling Earth's magnetic field. A magnet has no idea (so to speak) which direction is geographic north.

Any source that tells you that a magnet points geographically north is only as correct as the statement that geographic north and magnetic north are the same direction.

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You must have seen this image of the earth mapped on a globe before, this one shows a satellite orbit:

globe

The axis of the earth's rotation points to the north pole star and navigation calculations use its location on the celestial sphere to define latitude.

Since ancient times people defined north by the polaris star direction. They also noticed that magnets pointed in that direction, too, and named the magnet's pole accordingly, and used compasses for navigation.

We now know how magnetic fields arise , and have observed that there is a difference in the direction between the magnetic and celestial north. In fact the magnetic pole has been moving continuously. The magnetic field of the earth arises from core magnetism and due to fluid mobility changes the magnetic north by kilometers per year.

Earth's north magnetic pole is racing toward Russia at almost 40 miles (64 kilometers) a year due to magnetic changes in the planet's core, new research says.

The core is too deep for scientists to directly detect its magnetic field. But researchers can infer the field's movements by tracking how Earth's magnetic field has been changing at the surface and in space.

Now, newly analyzed data suggest that there's a region of rapidly changing magnetism on the core's surface, possibly being created by a mysterious "plume" of magnetism arising from deeper in the core.

And it's this region that could be pulling the magnetic pole away from its long-time location in northern Canada, said Arnaud Chulliat, a geophysicist at the Institut de Physique du Globe de Paris in France.

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