© Sue Murdock
A great example of what's known as a sun halo was spotted over Cape Coral on Saturday.

A sun halo is when an enormous ring appears to form around the sun. Though the effect appears rather remarkable, it's actually a somewhat common occurrence.

Sun halos are formed when cirrus clouds are present in the atmosphere. These are clouds forming well above the Earth's surface, usually at heights greater than 22,000 feet. The temperature in the atmosphere this high up is cold, so instead of being made up of tiny water droplets like clouds closer to the surface, cirrus clouds are constructed with small ice crystals.

When the sun's light hits these small ice crystals in the sky, the light is bent in the same manner as it is when entering a prism. This is what generates the circular structure we see when sun halos form.