What is a "Halo"?
Published: Jul 28 2011 11:28:08 AM EDT
Have you ever seen a single ring of color around the sun or moon?
It is called a halo, and it occurs more frequently in nature than a rainbow.
When the sky is draped in a high, thin overcast of cirrus clouds.
The six-sided ice crystals that make up those clouds act as the prisms that separate the sun's light into colors.