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Sun Pillars
bbc.co.uk/cornwall/weather/uppersunpillar.shtml
Link is dead. The MIA webpage can be accessed via the Wayback Machine:
https://web.archive.org/web/2004072...c.co.uk/cornwall/weather/uppersunpillar.shtml
More stuff on light pillars:
islandnet.com/~see/weather/eyes/pillars.htm
Link is dead. The MIA webpage overview of light pillar / sun pillar phenomena can be accessed via the Wayback Machine:
https://web.archive.org/web/20040810174155/http://www.islandnet.com/~see/weather/eyes/pillars.htm
Spectacular happenings in the dawn sky
The beginning of the Upper Sun Pillar display.
On Sunday 16th May west Cornwall experienced a spectacular Upper Sun Pillar.
It was formed from ice crystals in the atmosphere.
FACTS
Ice crystals form in a wide variety of shapes and sizes: stars, needles, columns and plates.
When bright light passes from the sun, moon or an artificial light source through a portion of the sky containing a concentration of ice crystals, magical apparitions often appear.
The crystals focus, scatter, bend, split and reflect the light rays into a kaleidoscope of optical phenomena: arcs, glories, halos, pillars and sun dogs.Ice crystals form in the atmosphere in a wide variety of shapes and sizes and when bright light from the Sun, Moon or even a street light passes through a part of the sky containing them, some interesting shapes develop.
One of these is the Light Pillar and the most commonly seen form is the Upper Sun Pillar. It extends from 5 to 10 degrees above the sun when it is just below or just below the horizon.
The ice crystals are in the form of flat hexagonal plates and these reflect the light externally and internally downwards. When the crystals are below a line between the observer and the sun they can reflect the light upwards to form a pillar that appears to be under the Sun.
Because the light forming the pillar is reflected, the pillar takes on that colour so that it is red or orange when close to the horizon and becomes yellow or white as the sun rises.
This change can be seen in the pictures on this page.
They were all taken around dawn on Sunday 16th of May 2004, one by Amanda Jenkin and the others by BBC Radio Cornwall's Chris Stumbles
Link is dead. The MIA webpage can be accessed via the Wayback Machine:
https://web.archive.org/web/2004072...c.co.uk/cornwall/weather/uppersunpillar.shtml
More stuff on light pillars:
Link is dead. The MIA webpage overview of light pillar / sun pillar phenomena can be accessed via the Wayback Machine:
https://web.archive.org/web/20040810174155/http://www.islandnet.com/~see/weather/eyes/pillars.htm
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