An Aurora

Finally, some of the excited particles in the radiation belts can plunge into the upper atmosphere, where they collide with oxygen and nitrogen. These collisions-which usually occur between 40 and 200 miles above ground-cause the oxygen and nitrogen to become electrically excited and to emit light (fluorescent lights and televisions work in much the same way). The result is a dazzling dance of green, blue, white, and red light in the night sky, also known as aurora borealis and aurora australis (northern and southern lights). Auroras can appear as colorful, wispy curtains of light ruffling in the night sky, or sometimes as diffuse, flickering bands. Either way, they tell us that something electric is happening in the space around Earth.

Different types of aurora