A. Reflections of sunlight by polar ice fields
B. Fast-moving charged particles colliding with air molecules
C. Burning oxygen caused by the intense sunlight at high altitude
D. The combination of molecular and atomic oxygen to form ozone
E. Scattering of sunlight in the upper atmosphere
An aurora is caused by the streams of electrified particles (which are emitted by the sun) trapped in the magnetic field of the earth. It is produced when this magnetosphere is disturbed by the solar wind carrying the charged particles. Auroras are seen in latitudes of around 70 degrees.
