Have you ever seen more than one sun in the sky?
If you're from the Midwest, you may say "yes" while most people on Earth answer differently. That's because most people on our planet live in warm climates, where the "Parhelion" doesn't occur and another reason why most people have never seen the Northern Lights.
There are several terms used to describe this optical phenomenon of the Parhelion, where three suns are seen on the horizon. It can be called a "sun dog" or a "22-degree halo."
Here's how it works
Normally, the sun's rays shine directly into your eyes. However, when there are hexagonal ice crystals high up in the atmosphere, but not enough to shield the rays of the sun, the light is refracted at precisely 22 degrees. The refraction essentially bends some of the light toward our eyes.
Because of the "Bernoulli Effect," these ice crystals only rotate in one direction. That creates the perfect optics where the light from the sun is bent toward our eyes, creating an illusion of three suns.
Because this phenomenon requires hexagonal ice crystals at high levels of the atmosphere, Parhelions are quite rare and only occur in frigid conditions.
You're most likely to see these in the Upper Midwest and Canada, especially when the sun is close to the horizon. This past weekend's show was particularly vivid, thanks to near-perfect atmospheric conditions.
- Meteorologist Eric Sorensen