What Causes an Aurora?
There are three major components to an aurora:
Gases in the atmosphere,
the sun,
and Earth's magnetic field.
As the solar wind pushes against the magnetic field and changes its shape, it excites the electrons moving in the magnetosphere so that they begin to move fast. As the particles move faster and follow the magnetic field lines into the magnetic poles and into the atmosphere, they collide with gas atoms.
These collisions cause the gas atoms to become “excited”. The gas atoms momentarily lose grasp of their electrons, but because their attraction is strong, they grab them back again. As the electrons move back to their atom, energy is given off in the form of light.
The light that is given off is what you see in the colorful auroras.Photo by Dick Hutchinson
Photo by Jan Curtis
