Magnetic north just changed. Here's what that means.
Magnetic north has never sat still. In the last hundred years or so, the direction in which our compasses steadfastly point has lumbered ever northward, driven by Earth's churning liquid outer core some 1,800 miles beneath the surface. Yet in recent years, scientists noticed something unusual: Magnetic north's routine plod has shifted into high gear, sending it galloping across the Northern Hemisphere—and no one can entirely explain why.