APOD: 2005 March 9 - A Sun Halo Over Tennessee
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2005 March 9
A Sun Halo Over Tennessee
Credit & Copyright: Vydor
Explanation:
Sometimes it looks like the Sun is being viewed through a large lens.
In the above case, however, there are actually millions of lenses: ice crystals.
As water freezes in the upper atmosphere, small, flat, six-sided, ice crystals might be formed.
As these crystals flutter to the ground, much time is spent with their faces flat, parallel to the ground.
An observer may pass through the same plane as many of the falling ice crystals near sunrise or sunset.
During this alignment, each crystal can act like a miniature lens, refracting sunlight into our view.
The above image was taken near sunset last month
Winter Solstice near Nashville, Tennessee, USA.
Dramatically visible behind neighborhood houses and trees and above the cloud deck is the 22 degree halo created by sunlight reflecting off of atmospheric ice crystals.
Tomorrow's picture: california red