SEATTLE - Jack from Seattle says he observed a green flash on the sun as it was setting along the Oregon Coast. The phenomenon is quite rare, but spectacular to see. It's usually noticed just as the top tip of the sun at sunset or sunrise.
It works on a similar level as to why the sun looks red as it sets, where the shorter wavelength colors of light - the blues, greens and yellows, become scattered in the atmosphere while the longer red and orange light is able to survive, giving the sun a reddish tinge.
The theory with the green flash is that if the atmospheric conditions are just right, you can get a brief period where the green light bends in such a way where you can see it. Check the Ask Steve Web site for links to more information.
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