Studies show that only one in three Americans can see the Milky Way at night from where they live. Recognizing this problem, a group of astronomers and biologists began a campaign to take back the night.
The Dark Sky movement was created for the purpose of protecting and preserving the nighttime environment and our heritage of dark skies. Dark Sky compliant fixtures are constructed to reduce the effects of light pollution - that luminous glow that haloes cities and brightly lit suburbs, which prevents us from seeing stars and disrupts the behaviors and environments of nocturnal wildlife.
Light pollution is one of the most rapidly increasing contributors to the destruction of our natural environment that is caused by humans. The adverse effects of artificial light pollution is evident in a large number of plants and animals, from nocturnal migratory birds, which use the light from the moon and stars for navigation; to sea turtles, whose hatchlings are fatally disoriented by the city lights and crawl inland rather than out into the ocean; and even tree frogs, whose hormone production is altered by excess light exposure, causing variations in their natural biological rhythms.
Dark Sky compliant fixtures:
- Produce downward projected, "full cut off" light.
- Shield light from being emitted upward into the sky.
- Direct light in a low spread manner so as not to affect surrounding areas.
You can do your part to put the real light show back in the sky by choosing Dark Sky compliant exterior lighting for your home.
Dark Sky Compliance and Safeguarding Starlight
The Perseid meteor shower occurs every August as the Earth passes through the tail of Swift-Tuttle, a comet with an intersecting orbit around our Sun.
This meteor shower has been a part of human history for the past 2,000 years although our ancestors would be disappointed by the light show we see these days, especially if they were viewing it from the heart of a metropolitan area.
Light pollution has all but destroyed this annual event in metro areas and much else besides in the night sky as human sprawl results in ever more artificial light emanating nightly from parking lots, skyscrapers and urban centers. The problem was already growing out of control by 1997 and so the Commission Internationale de l’Eclairage (CIE) established four environmental zones to set a basis for outdoor lighting regulations.
These zones were then used as guidelines in the development of the USA Pattern Lighting Code, which sets out to provide lighting-zone ratings for different regions in the country and is an influential document in the legislative fight of the International Dark Sky Associatio(IDA) – a nonprofit organization that advocates for the protection of the world’s night sky.
The IDA has been fighting light pollution since its inception in 1988 and its efforts and support of the Lighting Code has resulted in the lighting industry’s development of Dark-Sky compliant fixtures. The light these fixtures emit must be projected downward and shielded from escaping into the night sky to meet specifications.
Light pollution harms much more than our view of an occasional meteor shower. Studies show that it has a detrimental impact on several species of plants and animals, including nocturnal migratory birds that use celestial navigation and sea-turtle hatchlings that are disoriented by city lights.
Although federal regulation is pending, many states have elected to enact laws against light pollution, and major cities are choosing to enforce Dark-Sky compliance.