When we look up and see the Northern Lights, we are only seeing a tiny section of a huge auroral oval.

Auroras form in rings centered over the Earth's Geomagnetic Pole - the pole of the Earth's geomagnetic field closest to the Geographic North Pole (True North).

The geomagnetic field surrounds the Earth and extends into space as the magnetosphere, and the Geomagnetic Pole is the centre of the region around which the Northern Lights can be seen.

As the rings center around the geomagnetic poles and not the geographic poles (which are the center of the Earth's rotation), the auroral ring is not consistent with patterns of daylight and darkness caused by that rotation. Rings form around the North and South poles at the same time, although they can't be seen when it is not dark.

The most active part of the ring moves as the Earth's magnetic field shifts because of changes in the solar wind or the currents that cause the aurora.