A New Year’s Day light display in the sky above Los Alamos taken with an iPhone near Ashley Pond Park. Photo by Sean Reilly
A New Year’s Day light display in the sky above Los Alamos taken with an iPhone from a porch in White Rock. Photo by Douglas Reilly
A light display visible across Los Alamos taken by a LANL photographer using a fish-eye lens in 1988 from the roof of the old Administration Building. Courtesy/Douglas Reilly
Douglas Reilly explains that the sun with sun dogs are so-called because they follow (dog) the sun. Sean Reilly’s photo includes much of the circle that passes through the sun dogs and a lovely arc above the sun. The technical names of these features are: sun dogs (parhelia), circle (22 degree Halo), arc above the sun (circumzenithal arc). These are caused by ice crystals aligned in certain ways high in the atmosphere.
“There are a couple dozen such features described over the centuries and photographed when that became possible,” he said. “The 1988 display is the best I’ve ever seen; it approaches the complexity of some of the best described over history. As Prof. Arons often said, ‘the names are not important, understanding is.’”
There are at least nine features in the photo.
“I’ll just name the circle that passes through the sun and sun dogs and is centered on the zenith, the center of the photo and the top of the sky,” Reilly said. “This is called the parhelic circle, and the two brighter spots are the 120-degree parhelia. There is a third slightly brighter spot on the parhelic circle directly opposite the sun, the anthelic point. Displays like this are rather more common in Antarctica as are ice crystals in the air. The brother of a colleague of mine published a book of such photographs and spent time in Antarctica.”
Reilly added, “In our modern world it is not common that we look up high in the sky. Unfortunately, this means many of us miss some of nature’s beauties. If any of you are interested in learning more about these phenomena or just want to see some neat pictures, I recommend this book: Rainbows, Halos, and Glories, by Robert Greenler.”