Is there a “green flash” in the...

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Is there a “green flash” in the Caribbean at sunset? I have heard of it but never seen it.

Answer

On rare occasions, the Sun may look bright green for a moment as its last tip is setting. This green flash is caused by the greater refraction of the green wave band; the red rays of light are hidden below the horizon, and the blue and violet are scattered in the atmosphere. The flash is best seen when the air is cloudless and the horizon is well-defined, as on an ocean.