What causes the aurora borealis (Northern Lights)?

The aurora borealis, or Northern Lights, is caused by the interaction between charged particles from the Sun and Earth’s magnetic field. When these particles collide with atoms in the Earth’s atmosphere, they release energy in the form of light, creating the colorful bands of the aurora. The most common colors are green, pink, and purple, but the display can also include red and yellow hues. The aurora is most visible in the polar regions, where the magnetic field is strongest.