Earth's Moving Magnet

 

Here's a recent image from NOAA showing the variation in Earth's magnetic north pole over the past 10 years. These variations in the magnetosphere are due to circulation patterns in Earth's molten core, and are quite common in nature. So common in fact that Earth occasionally swaps the north and south poles as a result of motion in the liquid core. 

Reversal occurrences are quite random, with some periods lasting as little as 200 years. Scientists have documented 183 reversals over the last 83 million years. The latest, known as the ‘Brunhes–Matuyama reversal’, occurred roughly 780,000 years ago.

Images Courtesy of: NOAA