A moonbow is a rainbow that appears in moonlight. Light from the moon must be refracted through a mist of water in order for us to see the effect. Photographer Wally Pacholka captured this effect at the edge of Haleakala crater on the island of Maui. The large "star" in the picture is Mars.
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Link to Pacholka's website. -via
ArbroathPS: There's a state park near my hometown that has a moonbow every month if the weather is clear.
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