What is Skyglow?

This is the diffuse luminance of the night sky. It involves any scattered light seen at night, including natural ones like starlight, zodiacal light and airglow, but usually refers to luminance arising from artificial lighting ie. light pollution. This stray light, direct or reflected off the ground or other surfaces, is partially scattered back to produce a diffuse glow that is visible from great distances.

photo taken on our trip to Scotland of the Northern Lights

On the left of this photo, you can see star trails, along with the pink glow of the Northern Lights. However, on the bottom right hand side, you can see the light pollution from Dounreay power station, which is reflected in the clouds in the top right corner.