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Look for the legendary green flash

The green flash image at the top of this post was taken by Jim Grant, an EarthSky friend on Facebook. He captured it off the coast of Ocean Beach, California and identified it a mock mirage green flash.

It’s not hard to see a green flash with the eye alone, when sky conditions are right, and when you’re looking toward a very clear and very distant horizon. That’s why those who live near an ocean tend to report green flashes most often. A sea horizon is the best place to see them. To see a green flash, you must be looking just at sunset, at the last moment before the sun disappears below the horizon. Be careful and don’t look too soon. If you do look too soon, the light of the sunset will dazzle (or damage) your eyes, and you’ll miss your green flash chance that day. But if you wait – looking away until just the thinnest rim of the sun appears above the horizon – that day’s green flash may be yours.

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View larger. | Jim Grant caught this green flash on April 27, 2012 off the coast of San Diego.

There are many different types of green flash. Some describe a streak or ray of the color green … like a green flame shooting up from the sunrise or sunset horizon. The most common green flash, which many people describe, is a flash of the color green seen when the sun is nearly entirely below the horizon.

Green flash captured by Mike Baird. Used with permission.

You need a distant horizon to see any of these phenomena, and you need a distinct edge to the horizon. So these green flashes, streaks, and rays are often seen over the ocean – but you can see them over land, too, if your horizon is far enough away. Pollution or haze on the horizon will hide this instantaneous flash of the color green.

If you’re interested in green flashes, Andrew Young’s green flash page is great. He also has a page of links to pictures of green flashes taken by people from around the globe.

Here’s another good article about the green flash by Peter Michaud.

And here’s a rather subtle green flash video here. I had to watch it several times to convince myself I saw any green.

And, of course, Les Cowley at the great website Atmospheric Optics devotes many pages to the green flash phenomenon.

Bottom line: The green flash is legendary, and some people have told us they thought it was a myth, like a unicorn or a pot of gold at the end of a rainbow. But green flashes are very real. You need a distant and exceedingly clear horizon to see them at the last moment before the sun disappears below the horizon at sunset.

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Can you see a green flash? More tips, plus more pictures

Deborah Byrd

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