During an eve I spotted this enchanting rainbow above the forest.
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A rainbow is an optical illusion that can be observed whenever there are water drops in the air and sunlight shining from behind the observer at a low altitude angle.
The most spectacular rainbow displays happen when half the sky is still dark with raining clouds and the observer is at a spot with clear sky in the direction of the sun.
The result is a luminous rainbow that contrasts with the darkened background.