Astronomy Picture of the Day
    


A Sun Pillar Over Ontario
<< Yesterday 18.08.2011 Tomorrow >>
A Sun Pillar Over Ontario
Credit & Copyright: Rick Stankiewicz (Peterborough Astronomical Association)
Explanation: What is that on the horizon? No, it's not an alien starship battling distant Earthlings, but rather a sun pillar. When driving across Ontario, Canada in early June, the photographer was surprised to encounter such an "eerie and beautiful" vista, and immediately took pictures. When atmospheric air is cold, ice sometimes forms flat six-sided crystals as it falls from high-level clouds. Air resistance then causes these crystals to lie nearly flat much of the time as they flutter to the ground. If viewed toward a rising or setting Sun, these flat crystals will reflect sunlight and create an unusual column of light -- a sun pillar as seen above. Such columns of light are not uncommon to see, and a retrospective of past APODs that have featured picturesque sun pillars can be found here.

Challenge: Find blogs running longer than APOD.

January
February
March
April
May
June
July
August
September
October
November
December
 < August 2011  >
Mo Tu We Th Fr Sa Su
1234567
891011121314
15161718192021
22232425262728
293031



Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.

Based on Astronomy Picture Of the Day

Publications with keywords: Sun Pillar - clouds - ice crystals
Publications with words: Sun Pillar - clouds - ice crystals
See also:
All publications on this topic >>