Beach goers at South Carolina’s Isle of Palms spotted an extremely rare “fire rainbow,” which lit up the sky for nearly an hour. “Fire rainbows, which are technically called circumhorizontal arcs, occur in high-level cirrus clouds made up of tiny ice crystals. To produce the rainbow colors, the sun’s rays must enter the ice crystals at a precise angle to give the prism effect of the color spectrum. In addition, the sun must also be at an altitude of at least 58 degrees above the horizon,” according to meteorologist Justin Lock. Continue reading for more pictures.