Scientists in Japan Have Found a Detailed Record of the Earth's Last Magnetic Reversal, 773,000 Years Ago

Every 200,000 to 300,000 years Earth’s magnetic poles reverse. What was once the north pole becomes the south, and vice versa. It’s a time of invisible upheaval. The last reversal was unusual because it was so long ago. For some reason, the poles have remained oriented the way they are now for about three-quarters of …