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Light Pollution
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Light Pollution

What is light pollution?
  Light pollution is a by product of humans lighting objects or areas at night with improperly pointed or shielded sources. In other words light pollution is caused when light is pointing up to the sky rather than down to the earth. Here is a map of the world showing where light pollution is worst.
What's so bad about that?
  It's simple. The more light pollution there is, the less stars, meteors, and comets we see. Have you ever seen the Milky Way? Have you ever seen so many stars you can't count them? If you have been to a place where there is little light pollution you know how beautiful the sky is at night. If you have not, I suggest you try to get to a place like that and see for yourself. It is something that has to be experienced. You can not describe it in words on a page like this.
Why do we pollute?
  Many people today have no idea how beautiful the night sky is. If you have ever visited a place where light pollution is low and the milky way is glimmering in the night sky you know what I am talking about. Most often light pollution is not deliberate but rather it is caused by ignorance.
Who creates light pollution?
  Most often advertising is the source of light pollution. Light sources pointing up include billboards, store lighting especially car dealerships, landscape lighting, church steeple lighting, highway lighting.
What about residential lighting?
  Often home owners install lighting that shines out and up rather than down. Also many homeowners leave lights on all night. I have driven home form the observatory as late a 3:00 AM and counted hundreds of porch, yard, and flood light on.
Does reducing light pollution cost money?
  Absolutely not. In fact in most cases it savings can be significant. While there may be an initial investment in upgrading lighting fixtures, the energy cost savings will more than pay for that investment. For example ten low voltage walkway lights use less power than one flood light.
How can low voltage walkway lighting help?
  This type of lighting allows visitors to see their way to your door without lighting up the sky. These units will actually save you money on your electric bill. These systems often come with timers that will automatically turn them on and off for you. They also look much more attractive than a pair of flood lights pointing at your visitors. Keep in ming that light pointing in you eyes actually reduces visibility.
Is it just the stars we are worried about?
  Light pollution affects much more than just astronomical observation. The amount of pollution we create affects bird migration, nocturnal animal behavior, marine life migration, driver safety, public security, the environment, and the budget.
What is being done?
  Many states around the country have or are beginning to pass lighting ordinances, regulating the amount of light emitted, type of fixtures and even types of source.
What can I do?
  • Take a look at the lights around your house. Are they flooding the neighborhood with glare ar are the directing light toward the ground. Remember several small lights correctly pointed and shielded not only make seeing better, they make your home look more elegant. Less is more when it comes to proper lighting.
  • If you know of another resident or business that has really bad lighting, politely inform them
What is Light Trespass?
  Light trespass occurs when spill light is cast into another persons property. Because light trespass and glare are quite subjective, they are difficult to eliminate, but they can be minimized through good design practices.
What should I do if I am the victim of light trespass?
  If your neighbor or a business has created a condition where light is blatantly trespassing onto your property, begin with politely confronting the property owner. Take them out at night and show them the problem. They probably never considered it. Suggest possible solutions. If it seems that you will not make any progress with a stubborn neighbor, check with you township office. Many towns have ordinances dealing with light trespass.
What is a good lighting fixture?
  Simply put, a fixture that directs its light down rather than allow it to flow out and up.
Where can I find good lighting fixtures?
  The International Dark Sky Organization (IDA) has a list of manufacturers.
Where can I observe at dark sites with other astronomers?
  Star parties are observing events that are held year round all over the world. They are usually held at the darkest site near the club that sponsors them.
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