Thursday, September 1, 2011

Sundog over the Prairie

Living where I do in Florida, my view of the skies is rather limited by the surrounding trees.  When I walk through the overhanging oaks, pines and bushes at the edge of the prairies and emerge into their vast open spaces, it almost feels like a theater curtain parts in front of me, teasing my imagination in wonder at what lies beyond the vast expanse of sky in all directions.  The open view pushes my thoughts from the close up to the distant.  I like to look at the change of color in each part of the sky, to watch the birds winging their flight above and to see the clouds skirting by as they do their dance from the wispy to the billowing, becoming small in the perspective of distance. As I was walking in Paynes Prairie late one afternoon, watching the shadow of jet trails on the thin veil of clouds I turned and saw this beautiful sun dog!  Below my photo I have cut and pasted what I learned about them from Wikipedia.

"Sundogs are made commonly of plate-shaped hexagonal ice crystals in high and cold cirrus clouds or, during very cold weather, by ice crystals called diamond dust drifting in the air at low levels. These crystals act as prisms, bending the light rays passing through them with a minimum deflection of 22°. If the crystals are randomly oriented, a complete ring around the sun is seen — a halo. But often, as the crystals sink through the air they become vertically aligned, so sunlight is refracted horizontally — in this case, sundogs are seen.
As the sun rises higher, the rays passing through the crystals are increasingly skewed from the horizontal plane. Their angle of deviation increases and the sundogs move further from the sun. However, they always stay at the same elevation as the sun.
Sundogs are red-colored at the side nearest the sun. Farther out the colors grade through oranges to blue. However, the colors overlap considerably and so are muted, never pure or saturated. The colors of the sundog finally merge into the white of the parhelic circle (if the latter is visible)." ~ Wikipedia

Mary Jane Volkmann

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