Natural Phenomenon
Light Pillars
Light pillars are several pillars formed by light of sun
which appear when the temperature of the weather is about 4 celsius degree in
polar area. It seems as if a light of pillars which appear from the ground to
the sky. Sometimes during very cold weather, vertical columns of light beaming
directly upwards are visible. These are called light pillars and are created by
the reflection of light from ice crystals with near horizontal parallel planar
surfaces. The light can come from the Sun (usually at or low to the horizon) in
which case the phenomenon is called a sun pillar or solar pillar. It can also
come from the Moon or from terrestrial sources such as streetlights. Light
pillars are typically seen in polar of regions.
Light pillars appear when artificial light or natural light
bounces off the facets of flat ice crystals wafting relatively close to the
ground. When the light source is close to the ground, the light pillar appears
above the floating crystals. When the light comes from the sun or moon, the
light pillar can appear beneath them, too, as the light refracts through the
crystals.
A light pillar
is a visual phenomenon created by the reflection of the light from the ice crystals with near
the horizontal parallel planar surfaces. The light can come
from the sun
(usually at or low to the horizon) in which case the phenomenon is called a sun pillar or solar pillar. It can also come from the moon or from terrestrial
sources sun light pillars are a kind of optical phenomenon which is formed by
the reflection of sunlight or moonlight by ice crystals that are present in the
Earth's atmosphere. They are also called the crystal beam phenomenon.
The light pillar looks like a thin column that extends
vertically above and/or below the source of light. The light pillar is
prominently visible when the Sun is low or lies below the horizon. It normally
forms an arc that extends from five to ten degrees beyond the solar disc. Light
pillars can sometimes also be seen arising from the Moon.
Light pillars are formed by reflection from ice crystals with
roughly horizontal faces.
Light
pillars have also been known to produce UFO reports. Niagara Falls
is one such area, where the mist from the Niagara Falls causes the phenomenon
to appear frequently during the winter months, where the ice crystals interact
with the city's many upward facing spotlights to create prominent light
pillars. Light pillars could also be formed by man-made light sources, such as
streetlights.
A light pillar, or sun pillar, appears as a vertical pillar
or column of light rising from the sun near sunset or sunrise, though it can
appear below the sun, particularly if the observer is at a high elevation or
altitude. Hexagonal plate- and column-shaped ice crystals cause the phenomenon.
Plate crystals generally cause pillars only when the sun is within 6 degrees of
the horizon, or below it; column crystals can cause a pillar when the sun is as
high as 20 degrees above the horizon. The crystals tend to orient themselves
near-horizontally as they fall or float through the air, and the width and
visibility of a sun pillar depends on crystal alignment.
Light
pillars can also form around the moon, and around street lights or other bright
lights. Pillars forming from ground-based light sources may appear much taller
than those associated with the sun or moon. Since the observer is closer to the
light source, crystal orientation matters less in the formation of these
pillars.
Sources
of the images :https://www.google.com/search?q=light+pillars&tbm=isch&tbo=u&source=univ&sa=X&ei=s8PcVPmIEpPjuQTa-YDgBw&ved=0CC0QsAQ&biw=1366&bih=667
References
:http://www.atoptics.co.uk/halo/lpil.htm
