The National Park Service and the Night Skies
The National Park Service (NPS) is committed to "…conserve the scenery and the natural and historic objects and the wildlife therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations" (NPS Organic Act of 1916). This commitment includes the night skies and the lightscape of the parks. The NPS Night Skies division is committed to helping parks monitor the effects of light pollution and offer suggestions for the mitigation of any issues that may be present. Dan Driscoe, an NPS employee with the Natural Sounds and Night Skies Division said in 2001 "Unlike losing a species to extinction, topsoil to erosion, or virgin lands to development, the night sky is 100% recoverable."
The National Park Service defines a natural lightscape as the resources and values that exist in the absence of human-caused light at night time. Natural lightscapes are critical for night time scenery and nocturnal habitat. There are many species that depend on natural patterns of light and dark for navigation, predation and other natural processes. Light pollution can have a negative effect on the organisms within a park and can also reduce the enjoyment of park visitors.
What is Light Pollution?
Light pollution is the introduction of artificial light either directly or indirectly into the natural environment. Light pollution degrades the view of the night sky by reducing the contrast between faint extraterrestrial objects and the background of the luminous atmosphere. An example of light pollution is sky glow, sometimes referred to as artificial sky glow, light domes or fugitive light; which is the brightening of the night sky from human caused light scattered into the atmosphere. Another form of light pollution is glare, which is the direct shining of light. Both of these forms of light pollution impact the human perception of nighttime, natural landscapes and features of the night sky.