[Aztlan] Sun Dogs & Moonbows

[Bruce Rogers]

Listeros,

In answer to Paul Troemner's comment about fine dust possibly 
producing such phenomena, I would doubt it.

Part of the reason such effects do occur is because the transparency 
of the ice crystals allows refraction of the sun light.  Generally 
dust, unless it is made of crystalline, transparent material, would 
not optically behave in the same way to produce this effect.

And slightly jumping threads, Moonbows are actually colored, but they 
often are so transient and muted that the observer often cannot make 
out these pale colors.  I have observed very pale colored Moonbows in 
the Klamath Basin of southern Oregon in summer during nocturnal rain 
showers. The colors ranged from light gray to white to very pale 
yellow.

Cheers,
Bruce Rogers, earth scientist on a good, ice crystal-filled day