by APOD Robot » Mon Feb 08, 2016 5:14 am
Light Pillars over Alaska
Explanation: What's happening behind those houses? Pictured here are not
auroras but nearby
light pillars, a nearby 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. The featured image was taken in
Fort Wainwright near
Fairbanks in central
Alaska.
[/b]
[url=http://apod.nasa.gov/apod/ap160208.html][img]http://apod.nasa.gov/apod/calendar/S_160208.jpg[/img] [size=150]Light Pillars over Alaska[/size][/url]
[b] Explanation: [/b] What's happening behind those houses? Pictured here are not [url=http://www.geo.mtu.edu/weather/aurora/]auroras[/url] but nearby [url=http://www.atoptics.co.uk/halo/lpil.htm]light pillars[/url], a nearby phenomenon that can appear as a distant one. In most places on [url=http://apod.nasa.gov/apod/ap100713.html]Earth[/url], a lucky viewer can see a [url=http://apod.nasa.gov/apod/ap010313.html]Sun-pillar[/url], a column of light appearing to extend up from the [url=http://solarsystem.nasa.gov/planets/sun]Sun[/url] caused by flat fluttering [url=http://www.atoptics.co.uk/halo/xtalreal.htm]ice-crystals[/url] reflecting sunlight from the [url=http://www.nasa.gov/mission_pages/sunearth/science/mos-upper-atmosphere.html]upper atmosphere[/url]. Usually these [url=http://en.wikipedia.org/wiki/Crystal]ice crystals[/url] evaporate before reaching the ground. During freezing temperatures, however, [url=http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/opt/ice/sp.rxml]flat fluttering ice crystals[/url] may form near the ground in a form of [url=http://apod.nasa.gov/apod/ap140122.html]light snow[/url], sometimes known as a crystal fog. These ice crystals may then reflect ground lights in columns not unlike a [url=http://apod.nasa.gov/cgi-bin/apod/apod_search?tquery=%22sun%20pillar%22]Sun-pillar[/url]. The featured image was taken in [url=https://en.wikipedia.org/wiki/Fort_Wainwright]Fort[/url] [url=https://www.youtube.com/watch?v=sKVmdRCd52A]Wainwright[/url] near [url=https://en.wikipedia.org/wiki/Fairbanks,_Alaska]Fairbanks[/url] in central [url=https://en.wikipedia.org/wiki/Alaska]Alaska[/url].
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