Want to learn more about
Light Pollution?
When was the last meteorite shower you experienced? Or when was the last time you saw a falling star?
Sky-gazing has become almost impossible. However, a simple change in manufacturing, as well as an understanding of how to design light installations, will provide us with a much better night sky.
Light, just like any other technology, should be carefully deployed in order to avoid consequential damages and inefficiency.
For most of our planet’s history, our spectacular universe of stars and galaxies has been visible in the darkness of the night sky. From our earliest beginnings, the vast spectacle arrayed across the dark sky has inspired questions about the universe and our relationship to it.
The history of scientific discovery, art, literature, astronomy, navigation, exploration, philosophy and even human curiosity itself would be diminished without our view of the stars.
Today, the increasing number of people living on earth, and the corresponding increase in inappropriate and unshielded outdoor lighting, has resulted in light pollution—a brightening night sky that has obliterated the stars for much of the world’s population. Most people must travel far from home, away from the glow of artificial lighting, to experience the awe-inspiring expanse of the Milky Way as our ancestors knew it.
The negative effects of the loss of this inspirational natural resource might seem intangible. However, a growing body of evidence links the brightening night sky directly to measurable negative impacts on human health and immune function, on adverse behavioral changes in insect and animal populations, and on a decrease in both ambient quality and safety in our nighttime environment. Astronomers were among the first to record the negative impacts of wasted lighting on scientific research. However, for all of us, the adverse economic and environmental impacts of wasted energy are apparent in everything from the monthly electric bill to global warming.
In refreshing contrast to some of today’s complex and lingering environmental problems, many existing solutions to light pollution are simple, cost-effective and instantaneous. Recognizing when outdoor lighting no longer serves its function and becomes a pollutant is the first step towards choosing appropriate solutions.
Increased urban sky glow is responsible for the disappearance of the Milky Way from our night skies. For professional astronomers, the increasing distance to prime observing sites, well away from sources of air pollution and urban sky glow, becomes more problematic as economic and environmental energy costs continue to rise.
Amateur astronomers, meanwhile, find that prime observing spots are eradicated by commercial and residential development and must travel farther from home for a clear view of the skies.
Increasingly, the most important equipment needed to enjoy the wonders of the night sky consists of a map and an automobile with a full tank of gas.
Urban Sky Glow—the brightening of the night sky over inhabited areas.
Clutter—bright, confusing and excessive groupings of light sources, commonly found in over-lit urban areas. The proliferation of clutter contributes to urban sky glow, trespass and glare.
Light Trespass—light falling where it is not intended, wanted or needed.
Glare—excessive brightness that causes visual discomfort. High levels of glare can decrease visibility.
The adverse effects of light pollution extend well beyond astronomy. New research suggests that light at night may interfere with normal circadian rhythms—the 24-hour cycle of day and night that humans have used to maintain health and regulate their activities for thousands of years.
Light trespass, occurring when streetlights or a neighbor’s security light directs unwanted lighting onto our property or into our homes, contributes to a loss of natural darkness. Wildlife, too, is harmed by the unnecessary brightening of the night. From newly hatched sea turtles to migrating birds, fish, frogs, salamanders and lightning bugs, artificial night lighting disrupts the cycles of nocturnal creatures in potentially devastating ways. While research is still ongoing, it is becoming apparent that both bright days and dark nights are necessary to maintaining healthy hormone production, cell function and brain activity, as well as to normal feeding, mating and migratory behavior for many species, including humans.
In addition to paradoxically wasting resources, a nighttime environment that is over-lit results in lowered visibility, as direct glare from improperly shielded fixtures is often blinding. Light spilling into the sky does not light the ground, where we need it.
The redundant lighting found in many urban centers results in a clutter of lights that contribute to sky glow, trespass and glare while destroying the ambiance of our nighttime environment. Our eyes, when dark-adapted, have good natural capacity in low-light situations. However, when nightscapes are over-lit, eyes never have a chance to become dark-adapted, and areas adjacent to brightly lit areas become impenetrable, thereby reducing safety. Some communities have experienced a decrease in crime by reducing or eliminating nighttime lighting in appropriate areas.
Light pollution wastes money and energy. In the United States alone, billions of dollars are spent on unnecessary lighting every year, with an estimated $1.7 billion going directly into the nighttime sky via unshielded outdoor lights.
Wasted lighting in the US releases 38 million tons of carbon dioxide into the atmosphere annually, while unshielded outdoor lights are directly responsible for 1.2 million tons of carbon dioxide waste. Simply reducing and removing unnecessary lighting saves money and energy, often at minimal expense. Over-lighting the night neither improves visibility nor increases nighttime safety, utility, security or ambiance.
