I posted this because I just watched a documentary about the earth's core on the BBC and the stuff about the implications of the south-Atlantic anomaly fascinat

I posted this because I just watched a documentary about the earth's core on the BBC and the stuff about the implications of the south-Atlantic anomaly fascinated me. It's a few years old but worth a watch if you have an hour to spare: http://www.bbc.co.uk/iplayer/episode/b0148vph/horizon-20112012-4-the-core http://www.bbc.co.uk/iplayer/episode/b0148vph/horizon-201120...