Science & TechFact
The compass has pointed south many times before.
Earth's magnetic field is generated by flowing liquid iron in the outer core. Over geological history it has flipped polarity hundreds of times, most recently about 780,000 years ago. Lava solidifying on the sea floor records the field's direction like a tape, so we know the sequence. A reversal usually takes several thousand years, with a temporarily weak, multipolar field.
Useful: The field is currently weakening slightly and the magnetic north pole is drifting toward Siberia at around 40 kilometres per year.
Source: en.wikipedia.org