Is it just dusty?
"Renaissance Thinking About the Issues of Our Day"
This stuff is incredible to work with. Still bleeding edge, not ready for prime time use.
Woman in Phoenix, Arizona, films "dry rain" consisting of tiny particles falling from the sky. Watch closely and you will see them reflecting sunlight as they flutter to the ground.
And here are some interesting results for Phoenix air particulates, years 2008 and 2009. As you can see, the readings are alarmlingly high compared to the maximum safe levels: