Light Pollution Maps for North America


David Lorenz


In a recent post in Cloudy Nights’ Light Pollution Forum, David Lorenz published data that very strongly suggest that the original Light Pollution Atlas was systematically biased by the fact that snow was on the ground when the underlying satellite measurements were taken. Lorenz recalculated the light pollution for the U.S. and southern Canada based on snow-free satellite observations, and the whole northern part of the area came out roughly one full zone darker. That means that the original atlas overestimate the skyglow in this area by a factor of three --From the Map Room Blog.

Content last updated: July 16, 2012