Nine-year-old Margaret Roberts was captivated by what she saw in the sky over the French Cross in Morden, N.S. on Sunday. The true sun is on the left; the bright light on the ride-hand side of the photo is a sun dog.
The meteorological term is parhelion; if you see two of them, they are parhelia. "Parahelion" is from Greek parēlion, "beside the sun"; para, meaning "beside", and helios, meaning "sun."
These bright spots on either side of the sun often appear on the edge of a halo. They, too, are a type of halo created by light interacting with ice crystals in the atmosphere. Despite that ice requirement, they can be seen anywhere in the world during any season, but they are not always obvious or bright. Sun dogs are best seen and are most conspicuous when the sun is close to the horizon.
As for the origin of the common name “sun dog”, it’s a little less clear. In parts of the United Kingdom, sun dogs are known as weather dogs and are said to warn of foul weather.
I've also heard many people refer to these bright spots as little rainbows; there are, however, significant differences between rainbows and sundogs.
You see rainbows when you look away from the sun; you see sundogs when you look toward the sun. If the ice crystals are falling horizontally, then you see a bright point of light on either side of the sun.
The biggest difference between the two is that a rainbow usually signals an end to the rain, while a sundog often means that rain or snow is on the way. Next time you see a sundog, look out for wet weather!
In medieval times, the three bright lights were sometimes interpreted as the sign of the trinity, a sign of great fortune.
As you can see Margaret, sun dogs mean different things to different people around the world.
Grandma used to tell me that her parents referred to these lights on either side of the sun as false suns and believed if you spotted one, the weather was going to get colder. Well Margaret, it sure has.
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Cindy Day is the chief meteorologist for SaltWire Network