@GoogleEarthPics tweeted this photo of a rare rainbow-colored pileus cloud, a meteorological phenomenon produced by pure magic.

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OK, it’s only like 90 percent magic. A pileus cloud or cap cloud is a small lens-shaped cloud that sits on top of a larger cloud like a hat. They can form on regular cumulus clouds, storm clouds, ash clouds from volcanoes, and even some nuclear mushroom clouds. On a cumulus or cumulonimbus cloud, they indicate severe weather a-comin’ — they form because the cloud underneath is rapidly pushing air upwards into the cooler troposphere.

This rare iridescent cloud isn’t a special type of pileus — it just happens to be sitting in front of the sun at the perfect angle to refract it into a rainbow halo. That, or it’s fairies.

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