What impact does light pollution have on astronomy?

Many observers have given up looking at objects in the southwestern sky, because the light pollution is so bad in that direction. The City of San Diego once required the use of sodium vapor lights on city streets to reduce the light pollution at Palomar, but as the city grew, that law was allowed to expire. read more

Astronomy, Our Perceptions of Light, and the Impact of Light Pollution Action Spectrum for Melatonin Regulation in Humans: Evidence for a Novel Circadian Photoreceptor Effects of Artificial Night Lighting on Terrestrial Mammals. read more