Solar activity, like solar flares and coronal mass ejections, increases the frequency and brightness of the northern lights.

The Sun goes through cycles of activity about every 11 years. During periods called solar maximums, the Sun sends out more charged particles and stronger storms. These energetic particles hit Earth's magnetic field with more force, causing brighter and more colorful auroras that can be seen farther from the poles than usual. This is why some years are better than others for spotting the northern lights.