Let all the number of the stars give light
The Problems of Light Pollution -- Overview
Light pollution: Any adverse effect of artificial light including sky glow, glare, light trespass, light clutter, decreased visibility at night, and energy waste. Light pollution is not only a hinderance to astronomy, but it also impacts us directly.
Use the links above to learn more information about the different effects that light pollution causes. Light pollution is similar to the widespread long term damage a toxic chemical spill creates across the land. We ignore this at our own peril and we need to think about what this means for us.
Look at the picture at the right. Do you find yourself asking:
Could you tell by the sky color? Is it night or day there? Would kindergardeners there use a lot of orange for their drawings of the night? While it does look more like a futuristic city on Saturn's moon Titan, excessive and poorly pointed city lights creates a perversely unnatural orange night sky, such as in London, England seen here.
So, with my apologies to Dylan Thomas:
Rage, rage for the majestic wonder of the night.
Identifying Good Light Sources
Before we go into what light pollution is, let us first consider and define why we even use lighting, what good lighting is and what it should do. I know that this may seem terribly basic, but unless we take a small moment to consider these concepts, then we may disagree or misunderstand what is needed to be done.
Why do we even use lighting? - We are a diurnal species. This means that our eyes evolved to function best in the daytime lighting conditions. While we can function at night with a little bit of light with the rod cells in our eyes, say from the Moon, we do not function as well as other species that are truly nocturnal. So, outdoor lighting provides visibility for us to conduct day-like activities at nighttime. Correctly done, we then see good outdoor lighting as an attractive benefit for our communities. Because of our preferences for daytime light levels, and the very basic, primitive fear we feel for darkened places that could hide a predator (those that did not heed such feelings so long ago were, over time, eliminated from passing on offspring!), we very much like light. It gives us a feeling of safety and security, even if the feeling is sometimes inappropriate for a particular situation.
Light can be used to enhance a theme or goals of the community when highlighting somoething it is proud to display. But that one aspect is so increasingly abused by so many that the displayed item just becomes hidden in the ever greater visual noise and clutter. As such, bad lighting is so pervasive and common now, that it is hard for people to recognize that it is so. Yet, there still should be some basic ideas or concepts that everyone would probably agree on that we should expect about what good outdoor lighting to provide.
Good Outdoor Lighting Should:
The second and the third concepts everyone would naturally agree upon, no one wants our resources or money to be intentionally wasted, nor does anyone want our lights to directly cause harm to the environment that we all depend on or to ourselves. The last two concepts are covered down below.
See what's lit, not the light - Believe it or not, it is that first concept, to
It is an incredibly simple concept. However, more often than not, what can only be seen is the lights' source
and not the area around it that needs to be illuminated. Sunspots on the Sun have a similar problem. While they look dark to us,
sunspots themselves DO shine out light. However, they are so overpowered by their surrounding, brighter photosphere surface
regions that they look dark. Likewise, decorative lighting in some kind of glassy-brassy housing fixture (or
In general, the guiding principle to good lighting can be summed up in this concept:
no light should ever be emitted above
Once this simple guideline is followed, a great deal of the problems regarding light pollution are immediately dealt with and solved.
However, if that principle is not followed, then we encounter a variety of problems from light pollution. The immediate problems that poor lighting can cause are shown below. Other more long term and damaging problems are listed on the other pages linked in the menu above.
Identifying Light Pollution
Light pollution is light that is not being efficently or completely utilized and is often pointed outwards or upwards and not downwards. Hence it is light that is often found to be rude or oppressive to the non-owners of the light. How so? Well imagine spending an hour outside at night to enjoy the stars, when someone walks up to you and shines a flashlight in your face. The light hurts your eyes and temporarily blinds you. Such an action is clearly rude. Yet no one thinks that it is equally and permanently rude that a person installs an outward pointing light on the side of a building to illuminate their grounds or parking lot or area around the building. Such people fail to consider just how far their security lights extend and bother other people. Such owners seem to think that if you wanted it to be dark, then you should go somewhere else. Yet the problem is that in today's society there is no where else to go to avoid lights at night. The darkest region in America, the American desert, can still see the lights of Las Vegas from 250 miles away. Such owners have, in all probability, chosen to locate themself to be close to where people live and work. I can guarantee that the other people, downlight from them, did not move to be near that offender's light.
So let us cover some basic definitions about light pollution:
The following pages will present some arguments against light pollution. Please spend a moment going through them and learn how light pollution negatively affects you, in so many ways. As there is no staff, except for myself, these pages are being filled in slowly. I'll update the pages over time when I get new information, read more papers, or take more pictures. Please be patient with me and please be pro-active yourself.
If future generations are to remember us with gratitude rather than comtempt,
we must leave them more than the miracles of technology.
Florida Atlantic University
Boca Raton, Florida
E-mail: evandern at fau dot edu
Phone: 561 297 STAR (7827)
light pollution, general effects, basic definitions, Florida, Palm Beach County, Broward County, Miami Dade County