Fog in the valleys below my house with the central bulge of the Milky Way stretching above. Single 2 minute exposure using the "Magic Glove" technique to properly expose the Milky Way and expose the foreground at the same time. Twin glows on the horizon are from small towns over 30 miles away. If the sky is completely clear I don't see this light pollution but because there is a layer of cloud over them in this shot the light is refelecting back down off the clouds. Green cast above the cloud layer is airglow and is similar to aurora (although not as spectacular) and it is caused by high energy particles interacting with natural oxygen in the upper atmosphere.