by logmark » Sun Mar 07, 2010 2:33 pm
The appearance of a "column" doesn't warrant a notation that a column actually exists. No differently than an apparent "column" of light seems to rise vertically from a cold winter night lamp post, this light pattern is created in horizontal space over some distances.
In this case, with the sun very low, the ice-laden layer must have been relatively low to the ground to be reflecting or refracting the sun's rays over the horizontal distances necessary to form the apparent "column" - thus the rarity even in areas of common cold and sun. Still air over large areas/distances, very cold temperatures, an oriented ice crystal laden stratus, and a point light source and - poof - an arc of reflecting or refracted light between the source and the observer
which appears to the eye (or camera) as a column. No column. None.
Just chemistry, physics and geometry. Ah-h-h - and the beauty of it...
The appearance of a "column" doesn't warrant a notation that a column actually exists. No differently than an apparent "column" of light seems to rise vertically from a cold winter night lamp post, this light pattern is created in horizontal space over some distances.
In this case, with the sun very low, the ice-laden layer must have been relatively low to the ground to be reflecting or refracting the sun's rays over the horizontal distances necessary to form the apparent "column" - thus the rarity even in areas of common cold and sun. Still air over large areas/distances, very cold temperatures, an oriented ice crystal laden stratus, and a point light source and - poof - an arc of reflecting or refracted light between the source and the observer
which appears to the eye (or camera) as a column. No column. None.
Just chemistry, physics and geometry. Ah-h-h - and the beauty of it...