“…Generally a northern latitude summertime phenomena, noctilucent clouds (NLC) are the highest of the exotic clouds known to mankind and exist at the 82 kilometer layer of space. They cannot be seen when the sun is up, the sun must lie below the horizon between 6 and 16 degrees to illuminate them. ‘Noctilucent’ literally means “lit at night”. The specific makeup of these clouds is not known. Theory has it that they are made up of ice covered meteoric dust particles. First described in sky observations after the cataclysmic eruption of Krakatau Volcano in Indonesia in August of 1883, noctilucent clouds have since been specifically observed across the higher northern latitudes of earth. In this tranquil scene south of Denali State Park, the Alaska Range peaks of Foraker, Hunter & Denali loom in the mist as a massive display of noctilucent clouds graces the northern skies like waves in an atmospheric ocean. Shredded by winds of between 300–400 knots, these shapes are in constant flux and may cover entire continents in a single display..."