The Green Flash

There was a rush for the surface and as eyes turned southward, they saw a tiny but brilliant green spot where the last ray of the upper rim of the sun hung on the skyline. It lasted an appreciable length of time, several seconds at least, and no sooner disappeared than it flashed forth again. Altogether it remained on the horizon with short interruptions for thirty-five minutes.

–Richard Evelyn Byrd expedition

I think most humans would easily associate a sunrise or sunset with the colors red, orange, and yellow, or an amalgamation of shades in between those visible frequencies. The twice-daily ritual of our nourishing star is a magnificent event, no matter how many times one has seen it. The sun, with its vibrant horizon hues, is a favorite topic for photographers and painters.

But there’s a White-Whale of a solar phenomenon that leaves many visual artists chloro-filled with envy: the green flash.

Sometimes called the green ray, a green flash is a meteorological phenomenon that can sometimes happen at sunrise or sunset, usually for a duration of mere seconds. If it occurs, the flash usually looks like the photo above, appearing just above the sun’s disk. Very rarely, the flash can manifest as a ray shooting upward from the sun.

These flashes exist for the same reason as the other colors of sun activity: the earth’s atmosphere. Light from the sun is white, a combination of all visible colors. But the atmosphere has the ability to separate the light into different colors.

Couple this separating ability with another effect known as a mirage and you might be lucky enough to witness a green flash. We’ve developed a connotation of a mirage to mean something you see that isn’t real, but optically a mirage is when light rays are bent to produce multiple images of a real astronomical object.

For a great and easy explanation about how the flashes work, watch the following video:

The elusive flash has been a search and obsession for artists and explorers for hundreds of years. Jules Verne wrote an entire novel in 1882 based around the notion, called The Green Ray. He was so taken with the flash he incorporated into his 1905 work The Lighthouse at the End of the World, as well. William S. Burroughs tosses the flash into 1981’s Cities of the Red Night.

It even shows up in the Pirates of the Caribbean film series. In 2007’s At World’s End, the flash signifies a soul coming back from the dead.

For you true nerds out there, in the Pokemon Sun & Moon series, Ash Ketchum’s Rockruff evolves into Lycanroc as the flash happens at dusk, revealing a brand-new type of Lycanroc that had not yet been known, the Dusk Form. I have no idea what that means. It forms into some sort of werewolf-legendary-giant-bird hybrid? That’s a powerful green flash!

According to San Diego State University, the flash can manifest in four different types: inferior-mirage flash; mock-mirage flash; sub-duct flash; and green ray.

They claim two-thirds to three-quarters of all sightings are inferior-mirage flashes, which are the flattened oval shapes seen as a “last glimpse.” The majority of the rest of the experiences fall into the mock-mirage category, where “indentations seem to ‘pinch off’ a thin, pointy strip from the upper limb of the sun.” Less than one percent of reports fall into the final two categories. The sub-duct flash apparently makes the sun look like an hourglass that turns green. And, of course, the ray is a beam rising from the disk.

Photographers can spend a lifetime looking for the flash and need to be fortunate and prepared to capture it. There’s no special spot on the earth to see them. Really all you need is an unobstructed horizon and the right atmospheric conditions. These ingredients mean the ocean is a great location. Pilots, who can see the entirety of a horizon easily, often report seeing the flashes.

Have you ever had the pleasure of catching a green flash?

Mine eyes have not had the fortune to see one. Currently, my trinity of bucket-list astronomical wonders I hope to one day experience includes the northern lights, a full solar eclipse, and a green beam. I’ll take the two-second version, not even the longer type you can see near the poles, as described in the opening quote from the Byrd expedition.

For now, I’ll have to make do with the wonderful imagery and video that others have witnessed.