An Iridescent Chembow is caused by the diffraction of light. Cloud Iridescence occurs when sunlight is diffracted by water droplets to create an irregular-shaped rainbow. This effect can also be seen lighting up Chemtrails with a bright blob of spectrum-colors. The term Chembow is popularly used to apply to both the "bow" of the Sunring and the rainbow-colored patch of the Iridescence effect.
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