What Causes the Auroral Lights?High speed ions and electrons travel along magnetic field lines and impact the atmosphere in the region called the auroral oval. Atmospheric gases are excited by these high speed collisions and give off different types of light as they relax back to their normal states. The color and altitude of the aurora tell us which atmospheric gases are being excited.
Since blue, green and red light are being produced in various combinations at various altitudes, it mixes to give an incredible variety of colors (such as purple and pink). |
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