WHAT IS LIGHT POLLUTION?

What is Light Pollution? How could light ever pollute something? It disappears as soon as the lamp is turned off and no sticky toxic residue is left in its wake. This cannot be a form of pollution, can it? The answer is yes; light can actually pollute the outdoor environment and wash away the view of stars in the sky. As awareness rises around the world, this term is heard in more and more places. It is a curable problem and can be prevented through the application of well designed and applied outdoor lighting.
Light Pollution occurs in the three following forms:

1. It causes an atmospheric phenomenon known as sky glow. Have you ever noticed the clouds overhead glowing an eerie pink, white, or orange color before? This wasted light is known as sky glow. It happens because of poorly designed and improperly aimed light fixtures called luminaries. Luminaries that do not offer adequate shielding usually spill wasted light into the sky and across property lines where it does not benefit anyone. When light spills into the sky, it reflects off of tiny airborne dust and moisture particles. This happens even on very clear evenings, too. The sky glow phenomenon directly affects the scientific research of amateur and professional astronomers. It also affects everyone else who simply enjoys a dark night sky abundant with stars overhead. Sky glow is a curable condition, and we can still have adequate and safe illumination in the outdoor environment.


2. Another form of Light Pollution is when illumination crosses property lines. This is called Light Trespass. Most people today have experienced light trespass to some degree. When someone else's illumination shines through your windows at night it is light trespassing onto your property. This is not only a nuisance; it can also affect your safety. Light trespass can prevent you from using your property outdoors at night when wishing to gaze at the stars while lying on a blanket or viewing through a telescope or binoculars.


3. Light pollution also occurs when too much illumination is applied to an area and a condition called glare results. Glare is defined as a visible source of illumination that causes a reduction in visual performance or an irritation.

Nighttime lighting has become a necessary part of our society. If designed and applied properly, nighttime illumination can greatly enhance a given area without causing compromise to either safety, the view of the nighttime sky overhead, or flora and fauna in surrounding areas. More communities around the Nation are now adopting comprehensive outdoor lighting ordinances in order to control the appearance and improve night time safety and security in areas their under jurisdiction.