The spinning magnet: the force that created the modern world - and could destroy it

A cataclysmic planetary phenomenon is gathering force deep within the Earth.

The magnetic North Pole will eventually trade places with the South Pole.

Satellite evidence suggests to some scientists that the move has already begun, but most still think it won't happen for many decades.

All agree that it has happened many times before and will happen again.

But this time it will be different. Alanna Mitchell tells the fascinating history of one of the four fundamental physical forces in the universe, electromagnetism.

From investigations into magnetism in 13th-century feudal France and the realisation 600 years later in the Victorian era that electricity and magnetism were essentially the same, to the discovery that Earth was itself a magnet, spinning in space with two poles and that those poles aperiodically reverse, this is a utterly engrossing narrative history of ideas and science.