Aurora Borealis

The aurora borealis (northern lights) and aurora australis (southern lights) are natural light displays produced when charged particles from the Sun (solar wind) are funneled by Earth's magnetic field into the atmosphere at the polar regions, where they collide with atmospheric gases, producing curtains of green, red, blue, and purple light. The most intense auroras occur during geomagnetic storms following coronal mass ejections from the Sun. They can be seen across northern Scandinavia, Iceland, Canada, Alaska, and occasionally as far south as Florida and Spain during major storms. The colors reflect different gases and altitudes: oxygen at 60 miles produces green; at 200 miles, red; nitrogen produces blue and purple.