Green Flash Viewed from Sunset Cliffs, California
February 10, 2013
Photographer: Jim Grant
Summary Author: Jim Grant; Dave Lynch; Dave's Web site
The photo above shows a green flash as observed from Sunset Cliffs, San Diego, California on October 24, 2012. Though I’ve seen the Sun flash green on dozens of occasions over the years, this one had a unique appearance – it looked like blue-green lava flowing over a canary colored volcano. Actually, the term “green flash” is misleading; it implies a sudden brightening, while in fact the disappearing Sun is growing dimmer second by second.
Green flashes are short-duration appearances of usually green light from the top rim of the Sun. They’re not rare but can be tricky to observe. In very clear air, flashes can appear blue or even purple. Atmospheric refraction is responsible for the burst of light. The curved atmosphere acts like a prism, splitting sunlight into its different colors. Even though you can see green flashes with the naked eye, you’ll have more luck using binoculars or a small telescope and will be able to detect more detail. Of course, always use the utmost caution when looking at the Sun.
Photo details: Camera Model: NIKON D80; Focal Length: 300mm (35mm equivalent: 450mm); Aperture: f/5.6; Exposure Time: 0.0005 s (1/2000); ISO equiv: 200; Software: Microsoft Windows Live Photo Gallery14.0.8064.206.