It is said that to see a green flash will bring you good luck. So I hope that if you on the Mendonoma coast, you will take the time to watch the sunset. A green flash sometimes appears at the moment the sun is disappearing from view. This first photo was taken by Peter Cracknell. Note the emerald-green color and note the clear horizon.
The green flash is a photographable mirage, caused by light refraction. Here is a photo by Richard Kuehn showing the classic hour-glass, where the top of the sun seems to pinch off from the bottom. You can see a green flash at the top of the hour-glass. But there might have been a bigger green flash a moment after Rich took this photo.
If you are extremely lucky, a green flash will morph into a blue flash. This photo was taken by Allen Vinson and it also has hints of purple on the edges - it's very rare to get a photo of this.
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Allen also captured this green flash. Look! There are two green flashes in his photo.
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Allen always celebrates his green flash viewing with a green flash cocktail. Very civilized, Allen!
If you interested in learning the mechanics of a green flash, here is an article that might help: http://aty.sdsu.edu/explain/explain.html
I'll be watching the sunset tonight. How about you?
Thanks to Peter, Rich and Allen for allowing me to share their photos with you here.