Figure 6-14 The Northern Lights (Aurora Borealis) A deluge of charged particles from the Sun can overload the Van Allen belts and cascade toward Earth, producing auroras that can be seen over a wide range of latitudes. (a) View of an aurora from the Polar spacecraft imposed on a graphic image of Earth. Colors from blue to red indicate lowest to highest auroral activity. Auroras typically occur 100 to 400 km (62 to 250 mi) above Earth’s surface. (b) View of aurora over the north central part of the United States and southern Canada as seen from the International Space Station when it was over south central Nebraska. (c) Aurora borealis in Alaska. The gorgeous aurora seen here is mostly glowing green due to emission by oxygen atoms in our atmosphere. Some auroras remain stationary for hours, while others shimmer, like curtains blowing in the wind.