I really don't know where to put this. A few people have asked to see green flash photos. I could put it in Urban Legends, as many people I know
don't believe that it is a real phenomenon.
What is a Green Flash?
The basic cause of the color is atmospheric dispersion: refraction by air is
larger at shorter wavelengths. So, at sunset, the refractive delay of the sunset is usually a second or two longer for blue and violet than for red.
In general, then, the red image of the Sun (or of some miraged part of it) sets or disappears first, followed by yellow, green, blue and violet.
So why isn't violet the last color to be seen at sunset? There is another effect at work: atmospheric extinction. Both air molecules and aerosol
particles scatter the shortest wavelengths most strongly (which is why the sky is blue: the strongly-scattered blue light goes in all directions, so
we see it when we look anywhere in the sky). At the horizon, the path length through the air is very long, and the shortest wavelengths are almost
Also from the site Atmospheric Optics
The classical green flash, a brilliant glint of
green almost on the ocean horizon just as the sun disappears, relies on a mirage to magnify the usually small differences in refraction between red
and green light. The mirage occurs when there is warm air immediately over the ocean and the air temperature gradient changes rapidly with height,
i.e. the temperature profile is curved. For the flash to be visible the warm air layers must be below you.
First indications of something unusual are when a sliver of a 'second sun' rises from the horizon as the 'real sun' descends. The lower sun is an
inferior mirage (inferior because the image is below the real sun). As the sunset proceeds the lower sun eventually links with the upper sun to form
an Etruscan vase or omega shape. The two suns overlap more and more. At the moment when the suns are almost gone the vertical magnification between
the different paths of green and red rays is strongest. The green flash then shines forth.
What I'm going to show you is an Inferior Mirage Green Flash. This phenomenon has been my obsession for the last three years. I know that I have
to have a warm air layer over a cooler horizon, and I know I need some elevation above the horizon, but not too much.
I've taken well over 12,000 photos trying to capture this phenomenon in the past 3 years. Most evenings where it looks like I'll have a clear
sundown, I'll take 150 photos, and likely not keep any of them.
This is a green flash sequence. Incidentally, if there was a Nibiru dancing around next to the sun, please believe that I'd have held that photo up
high and would probably have more than just an honorable mention at Project Camelot by now
This is an example of an Estrucan Vase..... the beginning of the mirage, where the sun seems cupped at the bottom:
This time of year, I can shoot from my front yard, over the top of a building and catch a bit of the sea. I try to frame these between SOMEthing
besides just the sea and the flash.
At this point, the sun is about to decend out of sight, but due to the refraction of the rays and perhaps bending of them, the appearance of a
"suntip" is still there.
Nope, not a UFO, but it's not uncommon for the green flash to take on both a convex and concave appearance. You never know how it will be recorded
-- sometimes they look random, other times very sharp borders. At this point, the sun has actually decended below the horizon. The green is
beginning to flare.
I call this file "two seconds" because it was the longest duration green flash I've ever seen. I didn't use any filters for any of this. I
load everything from the camera into Adobe Photoshot, but you can see from the exif data that nothing has been modified, except for resizing it so it
would be accepted by our media portal. Incidentally, thanks much to Ashley for helping me figure out why I couldn't upload anything.
In three years, I've captured it six times. Of those six, I really like three of them. Spaceweather has one of them, and National Geographic the
Hope those that happened to wander in here liked the show. c'mon down here, see it for yourself. Prove to your friends that you don't have to
shoot through a Heiniken bottle. ha
Now I'm in hot pursuit of the legendary green RAY. Not a corpusculan ray, but said to be like a green laser. Yah. I can't wait.
[edit on 18-5-2009 by argentus]