An aurora is a spectacular natural light show that appears in the night sky near Earth's poles. Shimmering curtains of green, pink, red, and purple light ripple and dance across the darkness, sometimes covering huge portions of the sky. In the north, this phenomenon is called the aurora borealis, or Northern Lights. In the south, it's the aurora australis, or Southern Lights.

These lights happen when particles from the sun collide with gases in Earth's atmosphere. The sun constantly releases a stream of charged particles called the solar wind. When these particles reach Earth, our planet's magnetic field guides them toward the North and South Poles. As they crash into oxygen and nitrogen molecules high in the atmosphere, they create those ghostly, glowing colors.

People who live in Alaska, northern Canada, Scandinavia, or other far-northern places might see auroras regularly. Occasionally, when the sun is especially active, auroras can appear farther south than usual, giving more people the chance to witness one of nature's most breathtaking displays.