Glory and the Space Needle

Yesterday morning at the top of the Space Needle dawned sunny with low clouds on the horizon (see image), but around 7 AM low clouds pushed into Seattle, reaching the upper reaches of the Needle (shown below)

6 AM

 7AM

8:30 AM

 

But something beautiful and subtle occurred as the low clouds extended toward the Space Needle:  a glory, characterized by colorful, concentric rings.  Here are a few shots from the SpaceNeedle cam: 

It is not rare to see glories when flying above clouds when the sun is high in the sky.

Glories are optical effects that occur when you have the right configuration of sun and clouds. They result when light is scattered back to the viewer by a field of relatively uniform, small cloud droplets and is always opposite the sun (centered at the anti-solar point), just as the shadow of an object (like the Space Needle or aircraft) would be.   It is possible to realistically simulate the generation of glories using the equations describing electromagnetic waves and their interactions with droplets (Mie Scattering) as shown below (the upper left corner is the simulation):

Keep your eye out for glories next time you are flying.