Corona.

Moon or Sun corona.

Around the moon or the sun can a colored corona sometimes appear. The red color is seen at the outer edge of the corona The corona isn't different to the halo only by the appearance but to the physics behind it. Halo is created by the light's reflection and refraction in  ice crystals but the corona is created by the lights scattering (diffraction) of  the clouds water droplets. When there are thin altocumulus clouds, the corona can appear with lots of colored rings. The corona can appear around the stronger stars and planets too.

Pollen can create coronae too. They look somewhat different to the coronae created by water drops. The mechanism behind them is diffraction of the light by the pollen.


 
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