
December 18, 2013
Light Pillars over Finland

December 18, 2013
Light Pillars over Finland
A little universe, just for you
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APOD published December 18, 2013. Credit: Thomas Kast. A publication-date match, not a photo taken on your date. Independent of NASA.
What's happening behind those houses? Pictured above are not aurora but nearby light pillars, a local phenomenon that can appear as a distant one. In most places on Earth, a lucky viewer can see a Sun-pillar, a column of light appearing to extend up from the Sun caused by flat fluttering ice-crystals reflecting sunlight from the upper atmosphere. Usually these ice crystals evaporate before reaching the ground. During freezing temperatures, however, flat fluttering ice crystals may form near the ground in a form of light snow, sometimes known as a crystal fog. These ice crystals may then reflect ground lights in columns not unlike a Sun-pillar. While going out to buy cat food, a quick thinking photographer captured the above light pillars extending up from bright parking lot lights in Oulu, Finland. Free lecture: APOD editor to speak in NYC on Jan. 3
Image credit: Thomas Kast