This is a rare phenomenon called iridescent clouds. It occurs in the clouds with ...
volcanic dusts
sulphuric acid
detergent vapors
small droplets or ice crystals
The effect is similar to irisation. Iridescent clouds are a diffraction phenomenon caused by small water droplets or small ice crystals individually scattering light. Larger ice crystals do not produce iridescence, but can cause halos, a different phenomenon.
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volcanic dusts
sulphuric acid
detergent vapors
small droplets or ice crystals
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