The magnetic mystery at the center of the EarthEarth’s depths...
The magnetic mystery at the center of the Earth
Earth’s depths are a hellish place. More than 5,000 kilometers belowground, the iron-rich core scorches at temperatures comparable to the sun’s surface and crushes at pressures akin to the weight of 20 blue whales balanced on a postage stamp…
Image caption: In a computer simulation, magnetic field lines (top row) twist and curl around the Earth’s liquid outer core. This magnetism results from swirling, or convecting, liquid iron (bottom row). The simulation mimics the process of a polarity reversal in which Earth’s north and south magnetic poles swap. Such reversals, a sign of a strong magnetic field generator, are seen going back hundreds of millions of years in planetary history. Credit: P. Olson/Johns Hopkins Univ.