Did you know that the polarity of the earth reverses every few hundred thousand years? North becomes south and south becomes north, and for a short while we have little magnetism at all. Using a series of colour-coded animations, Co Hoedeman tries to condense some fairly complex theories of magnetism and planetary movement into a rather dry ten minute short feature but it is still informative and is quite effective at taking the basic dynamics and making them comprehensible to the uninitiated (i.e. me). There’s the best use of a pot of soup I’ve seen to illustrate volcanic activity here, though...