The Green Flash

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.

Onward.

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 completely removed.

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:


[atsimg]http://files.abovetopsecret.com/images/member/964c6029545f.jpg[/atsimg]

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.

[atsimg]http://files.abovetopsecret.com/images/member/a81944ac5ecc.jpg[/atsimg]

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.

[atsimg]http://files.abovetopsecret.com/images/member/188adae4459e.jpg[/atsimg]

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. [atsimg]http://files.abovetopsecret.com/images/member/7809287919c7.jpg[/atsimg]

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.
[atsimg]http://files.abovetopsecret.com/images/member/8a9bc1250c6c.jpg[/atsimg]


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 other.

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]

I have always wanted to see one of those. I thought it was balderdash. When I lived in Florida for some time. I would stare out over the gulf looking for one of these with no success.

Excellent pictures thanks for sharing them

I'd heard that it was just the negative of the afterimage on your retina that made you think you had seen a green flash. It's real? Very cool.
Nice pic by the way.

Thanks Wuk and Badger!

Yep, I get that a lot, as our national airline has a feature on their brochures that "hints" at the "possibility" that the green flash really exists.

Here's the first one I ever captured. It really demonstrates the variables of the phenomenon -- or at least Inferior Mirage green flashes.... it's a mirage of the sun coming "up" to meet the image of the real sun, and thus the reason it looks sorta like a UFO

[atsimg]http://files.abovetopsecret.com/images/member/21186b43365a.jpg[/atsimg]

How embarrassing. I hope OZ doesn't see this. I'm -- for whatever the reason -- unable to edit the OP...... no edit bar there.

So, okay, it's not a corpusculan ray, but a crepuscular. Corpusculan. what a marooon. Corpusculan sounds like either something pertaining to white blood cells or perhaps a ridge-headed reptoid from beyond the 17th density. ARRRGH!

Yet another thing that's not going to get better with age.

Very cool pics. A lot better than the other ones I have seen. Thank you for sharing and putting forth the effort to get this on camera!

Now what is this green ray you speak of?

reply to post by Vodo34861


much appreciated, Vodo!

The green ray....... from my first link,

There is a distinct, but related, phenomenon that really deserves the term “flash.” In this much rarer display, a green flash of the ordinary kind is followed (at sunset) by a brief ray or glow of green, which often appears to shoot up from the sunset point. It often accompanies, or follows, a “green dot”. These very rare displays are grouped under the term “green ray,” although the ray form is only one of several. Unfortunately, the term “green ray” has often been applied to the much commoner green-flash displays of the “green dot” form.

.

I've looked at many green flash photos, and have never seen a green ray photo. I"m not certain it ever HAS been photographed, which, of course, is primary criteria for hunting something -- not knowing if it exists or not

awesome argentus! i've been waiting to see these since your mention a while back.
i was in the navy for a while and the ship i was on was constantly gone underway and i always had an eye out for one. i had always wondered about the "green flash"; not knowing if it were a king neptune's tale and what not.

this is great. you should file it in fragile earth in ATS so more people get to see it.
thanks a ton and keep updating as you go!

i would love to see one in full rez. u2u me if that's possible i can point you to my ftp.
thanks for the photos!
good job!
zoo

[edit on 5/20/2009 by zooplancton]