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Luminous halos twirled above a Boeing CH-47 Chinook on a recent night around 11:30 p.m. local time at Forward Operating Base Jackson in Sangin, Helmand Province, Afghanistan, as helicopters ferried casualties and supplies in and out of the base. The photographer was independent journalist Michael Yon, a former U.S. Army Special Forces soldier who has covered Iraq, Afghanistan, and the Philippines... Read moreLuminous halos twirled above a Boeing CH-47 Chinook on a recent night around 11:30 p.m. local time at Forward Operating Base Jackson in Sangin, Helmand Province, Afghanistan, as helicopters ferried casualties and supplies in and out of the base. The photographer was independent journalist Michael Yon, a former U.S. Army Special Forces soldier who has covered Iraq, Afghanistan, and the Philippines with a camera. Helicopter pilots don’t have a name for the effect, but one explained to Yon, “Basically it is a result of static electricity created by friction as…dissimilar material strike against each other. In this case, titanium/nickel blades moving through the air and dust.” Yon says, however, that a researcher studying helicopter brownout emailed him to say that scientists are not 100 percent sure what causes the effect. Depending on the viewing angle, it creates dazzling little galaxies. View page