Aurora Borealis

Auroras are natural colored light displays, which are usually observed in the night sky, particularly in the polar zone.Auroras are now known to be caused by the collision of charged particles (ions (+) (-) ) found in the magnetosphere, with atoms in the Earth's upper atmosphere (at altitudes above 80 km). These particles travel into space with speeds of 300 to 1200 kilometers per second. A cloud of these particles is called plasma, and a stream of plasma coming from the sun is called solar wind.