The “fire rainbow,” which looks like an angel spreading its wings, is not actually a rainbow but a natural phenomenon known as a “circumhorizontal arc” or also called a “fire rainbow” or “circumscribed halo.” Forming this spectacle is extremely difficult—it only occurs when the sun is at least 58 degrees above the horizon, and sunlight refracts through a thick layer of cirrus clouds containing a high concentration of hexagonal ice crystals.

The view outside the window is super dreamy—a fantastical rainbow blanket in the sky

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