MOLINE, Ill. — A lot of you noticed quite a sight in our skies earlier this week. A large and beautiful sun halo! This phenomenon is not only beautiful but also a good example of how light from the sun can interact with different elements within our atmosphere to create some really stunning artifacts.
Likewise, you have also likely witnessed a moon halo at night, especially with a nearly full or completely full moon present in the sky.
A lot goes into the creation of these halos, including sunlight, moisture and a few other ingredients. Here's why we only see these types of halos under certain weather conditions.
There's an old weather saying that you might have heard before: Ring around the moon means rain soon. There is a lot of truth behind it, and we can also apply it to the sun as well.
If you have been an avid follower of weather patterns, you know that oftentimes high, thin, cirrus clouds typically spread overhead prior to a rain event. Most of the time, these clouds are moving overhead at some 20,000 feet above the ground. Contained within these clouds are millions upon millions of tiny ice crystals. Each one of these crystals acts as a mirror, bending and reflecting incoming light from the sun.
Why the perfect halo shape? The crystals are oriented and positioned perfectly with respect to our eyes in order for the halo to appear.
Similarly, a sun dog is also quite common in our skies during the winter months when suspended water vapor in the air freezes, creating more suspended ice crystals.
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