green flash

Sometimes, when the sun sets over water, the last part of the spectrum that reaches the observer is the green band of wavelengths.

The theory behind it is that shorter wavelengths get deflected more while they travel through the atmosphere, so they are the last part of the sun's image to reach the observer at sunset (or the first at sunrise). But light is not only deflected, but also scattered, and scatter increases with shorter wavelengths (the reason for a blue sky and red sunset in the first place). Under the right conditions, these two effects combine to scatter out the blue and leave only the green bent above the horizon.

Whatever the theory, this night in Sarasota it was quite impressive. We did a little dance of excitement on the beach.