Earth’s magnetic field surrounds our planet like an invisible force field – protecting life from harmful solar radiation by deflecting charged particles away. Far from being constant, this field is continuously changing. Indeed, our planet’s history includes at least several hundred global magnetic reversals, where north and south magnetic poles swap places. So when’s the next one happening and how will it affect life on Earth?

During a reversal the magnetic field won’t be zero, but will assume a weaker and more complex form. It may fall to 10 percent of the present-day strength and have magnetic poles at the equator or even the simultaneous existence of multiple ‘north’ and ‘south’ magnetic poles. Geomagnetic reversals occur a few times every million years on average. However, the interval between reversals is very irregular and can range up to tens of millions of years. READ MORE