Atmospheric
Optics
About - Submit Optics Picture of the Day Galleries Previous Next Today  
                 
Blood Red Sword, Wales

“The sun was setting in flames on the sea,  behind the four dark peaks of Snowdon; and suddenly, from sea to zenith, there rushed up the sky an even band of crimson light-fulgurous and burning; it was the rare phenomenon of the ‘blood red sword’, an omen of war even in Roman Times and Caesar’s Commentaries.”

John Hardwick quotes from G Withrop Youngs’s “An impression of Pen-y-pass,1900-1920”.  
 

He took this photo from 2000ft looking over Nant Gwynant with the sun setting behind Y Aran, an outlier of Snowdon.

“I look out for sun pillars but have not seen them very often.  This one was very visible.  It  moved as the sun set,  I have one photo where it looks as if the pillar is coming out of the mountain top!”

Images ©John Hardwick, shown with permission





Blood red pillars need blood red sunlight for sun pillars have no colours of their own.

One ray path for an upper pillar involves two refractions at plate crystal side faces. However, they are equal and opposite and there is no net dispersion into colours.