Light Pollution - Night Skies (U.S. National Park Service)
VIIRS-color-map-US-sm - Flagstaff Dark Skies Coalition
SKYGLOW - Bortle Scale Light Pollution Guide Map of North America. Help save the skies with SKYGLOWPROJECT.COM and the International Dark-Sky Association. | Facebook
Light Pollution Map - DarkSiteFinder.com
NASA Earth on Twitter: "Light and noise pollution from humans are negatively affecting bird populations in the United States. Scientists used light data from the @NASA/@NOAA Suomi-NPP satellite to study how light