Posted on 12/15/2015 1:23:59 AM PST by SunkenCiv
Explanation: What are those colorful arcs in the sky? Like rainbows that are caused by rain, arcs of sunlight broken up into component colors can also result when ice crystals floating in Earth's atmosphere act together as a gigantic prism. The top color arc is more typical as it is part of the 22 degree halo surrounding the Sun when hexagonal ice crystals refract sunlight between two of the six sides. More unusual, though, is the bottom color arc. Sometimes called a fire rainbow, this circumhorizon arc is also created by ice, not fire nor even rain. Here, a series of horizontal, thin, flat ice crystals in high cirrus clouds refract sunlight between the top and bottom faces toward the observer. These arcs only occur when the Sun is higher than 58 degrees above the horizon. The featured sky occurred to the northwest in the early afternoon last month over a street Diagonal of La Plata City, Buenos Aires, Argentina.
(Excerpt) Read more at 129.164.179.22 ...
[Credit and Copyright: Sergio Montúfar (Planetario Ciudad de La Plata, pna)]
http://www.freerepublic.com/perl/post?id=3372826%2C0
http://129.164.179.22/apod/image/1512/SolarArcs_Montufar_960.jpg
http://129.164.179.22/apod/image/1512/SolarArcs_Montufar_3792.jpg
I loved Bob Ross!
He added a “happy tree”!
Just a reminder that the Southern Hemisphere is going from SPRING into SUMMER right now. So as this was a November photo ("early afternoon last month"), that is why the Sun is higher than 58 degrees!
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
