Sundogs, or parhelia, are among the many marvels of the sky. They are caused by the refraction of sunlight through millions of ice crystals high in the atmosphere.
The plate-like crystals are suspended in cold cirrus or cirrostratus clouds. The crystals align horizontally as they drift down and bend the sun’s light at 22-degree angles.
That is what creates the bright spots, often in rainbow colors on either side of the sun, and sometimes on both sides. On rare occasions, the crystals create a full arch over the sun. The spots can also be simply bright white.
Sundogs are most frequently observed in the winter, when the atmosphere is cold. They most often appear at sunrise or near sunset, as in this recently taken photo.
Parhelia is the Greek word for “beside the sun.” Sundogs are members of the halo family that occasionally form around the sun and moon.
© Bruce Stambaugh 2026
Roadkill Crossing 
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