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Earth's Inconstant Magnetic Field Feature Summary

Worth a Look
Earth's Inconstant Magnetic Field
Earth's magnetic field has reversed quite a number of times--see NASA's Earth's Inconstant Magnetic Field for an overview and a model of how this reversal occurs. These reversals produced magnetic patterns on moving plates at the mid-Atlantic Ridge, as described in The Mobile Crust. For a timeline of the many reversals, see When Compasses Point South.
May 1, 2007 - May 16, 2007