Last Updated: Thursday, 27 March, 2003, 12:02 GMT Is the Earth preparing to flip? By Dr David Whitehouse BBC News Online science editor Finding the shifting magnetic pole It is not just the plot for a far-fetched science-fiction disaster movie. Something unexplained really is happening to the Earth's magnetic field. In recent years, the field has been behaving in ways not previously seen in the admittedly short time it has been monitored. Some researchers think it may presage a geomagnetic reversal when the north and south magnetic poles flip. Such speculation takes place as the science-fiction movie The Core goes...