The Earth's magnetic field directs solar particles toward the poles, which is why auroras mainly appear near the North and South Poles.

Earth acts like a giant magnet with magnetic north and south poles. The magnetic field shields the planet from most solar particles. But at the poles, the magnetic field lines curve down and funnel the particles into the atmosphere. This is why the northern lights mostly show up in places like Alaska, Canada, and Scandinavia, near the Arctic Circle, and the southern lights appear near Antarctica.