Sun dogs visible around southern Manitoba Monday had people wondering what they really are and how they form.
Sun dogs are bright flares that appear to the left and right of the sun. They are most easily seen when the sun is low in the sky.
Ice crystals in the upper atmosphere are responsible for this phenomena, according to information gathered from snowcrystals.com and atoptics.co.uk.
Ice crystals form in dry conditions or low humidity, whereas in environments with higher humidity, ice will form in a more branched pattern, resulting in snowflakes.
Ice crystals form hexagonal prisms and refract the light creating this effect. The key is the prisms remaining still as they fall. Only crystals with their prism axis roughly perpendicular to the sun’s rays will allow light to pass through two sides.
Sometimes, colours can be seen in sun dogs.
The colours will range from reds towards blues. Red light however is refracted less strongly than other colours so the inner edge’s red hue will be washed out in comparison to the blues, oranges and yellows.
Monday’s solar display had multiple phenomena — sun dogs as well as a 22° halo which is a complete circle around the sun passing through the sun dogs. Here is an example.
Here are a few other things you may be able to see when ice crystals line up correctly in the atmosphere.
While it is rare, it is not impossible to see many of these at the same time in the prairies. Just last month, this picture was taken in Manitoba.
PHOTO GALLERY: view images of sun dogs around Manitoba
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