On top of everything we already have to worry about, now we may have to add the Earth’s magnetic poles to the list. Nobody’s saying the poles will reverse themselves tomorrow, with north becoming south and vice versa, but scientists like to point out this is something that has happened regularly throughout the long history of our planet, and that it’s sure to happen again. When it does, look out.

Satellite data courtesy of the European Space Agency shows that the magnetic north pole is weakening, a potential indication that a reversal could be in the works, but this is something that occurs over the very long term. The last time the poles even attempted to reverse themselves was 40,000 years ago, and it last happened 780,000 years in the past. When it does occur, however, portions of the Earth will become exposed to everything space can throw at us, most importantly deadly radiation.

Our electrical grids won’t stand a chance, and what’s more, the reversal will likely take centuries. How did we manage 780,000 years ago? Well, we didn’t — Homo sapiens weren’t on the scene then.