Body 1
The causes of light pollution is Any external light source that permits light to go upwards or where it is not needed: * Unnecessary lighting - Lights that have no useful purpose or are lit when not needed. Some lighting isn't even necessary! The next time you turn on the light at night, ask yourself, "Is this light really doing anything constructive? Is this light really worth the extra money in electricity I am paying? Do I really need these lights to be on all night. * Excessive - Lights that are too numerous or simply too bright. Some lighting is just too excessive. When you pass by a bright streetlight or security light do you say, "Is this high brightness really necessary?" * Badly designed - Lights that are not properly shielded or have no shielding at all.( light is going everywhere which cost even more).
Streetlights and security lights are often the main problem. Although these lights do light up their intended targets, they also spill out, up, down and around them too! Light pollution in this case is caused by the light being directed above and beyond the target and up into the night sky.

Body 2
The effect of light pollution.
It is an unfortunate fact of today's life that most people are growing up unable to see the stars that our grandparents knew so well. The prime night sky exists only in pictures or at a planetarium. This is true not only in cities but also in suburbs and in rural areas where street lamps and other sources of "light pollution"
Heath Side Effects
Light pollution can increase the amount of headaches individuals get. It can also cause fatigue, stress, and anxiety. Some scientists believe that fake light may increase the risk of breast cancer.
Environmental Side Effects
Light pollution is changing the behavior of night animals, especially night birds. Birds use the moon and the stars for navigation, but when they fly into a lit area they become unstable. Light pollution can also change animals competitive interactions relations.

Body 3
The cost
It is extremely difficult to state just how much light pollution costs. While it is simple to say what may be lost or affected in some way, many of the things affected by light pollution are simply impossible to put a price tag on. For example, light pollution can degrade or destroy the view of the heavens but seriously it would be in depth whoever could put a specific cost on that. (It has to be said that a decent view of the night sky is priceless anyway!) That said there are a few things that we can start to price. Let us for example take the cost of electricity for lights
Conclusion
Reducing light pollution is not difficult. It just makes sense, but it does require that we understand the issues, light pollution is the easiest type of pollution to clean up. All it takes is switching off light sources that are unnecessary, and by choosing well shielded lighting fixtures. This will saves everyone money. And their will be some electricity left for the new coming generation.
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Ahmed Elalem
Sr. Hiba
Fri, march 3rd, 2012
Grade 9 ENG1D
Salaheddin Islamic school
Light Pollution

Introduction light pollution is light that is allowed to go where it is not wanted. Light pollution is often referred to “sky glow”. Some examples are a street light that shines in neighbors yard or bedroom’s window. The first three questions that has been asked by many people are : 1. What causes light pollution?. 2. What does light pollution affect? 3. What does light pollution cost?