This and the following National Park Service images are based on preliminary data collected by scientists featured in the related article. East and west are reversed, since the images show the sky as it appears overhead. The colors represent varying degrees of light pollution. In Utah's Arches National Park, Balanced Rock image, the orange-yellow area to the northeast shows moderate light pollution from Grand Junction, Colo. The green-yellow area to the south shows minor light pollution from Moab, Utah.
Courtesy of National Park Service