Exterior Lighting for a Dark Sky

As our cities grow larger and our lights get brighter, many urban and suburban areas are losing their view of the night sky. Light pollution is a topic that is gaining more attention around the world. It’s what keeps us from seeing the Milky Way during summer nights and reduces our overall nighttime view. In January 2018, Fountain Hills, Arizona responded to this problem and became the world’s 17th International Dark Sky Community.

Municipal lighting codes are vital for dark sky preservation, but homeowners can also take steps to minimize their contribution to light pollution. These simple and inexpensive tips can increase your home’s friendliness toward the night sky:

    • Shielded lighting. Shielded light fixtures direct outdoor lighting downward where it is needed to prevent it from polluting the sky with scattered light.
    • Warmer color temperature. New LED technology has created warmer colored lights that are easier on the eyes and reduce scattered lighting. Cool temperature lights can cause temporary night blindness for drivers and inhibits melatonin levels that affect healthful sleep. They also scatter light from particles in the air, adding to the light pollution problem.
    • Avoid uplighting. Landscaping lights that point upward to illuminate trees and buildings contribute to light pollution unnecessarily. Light your yard with creative light positioning and fixtures for an eye-catching effect that is environmentally sensitive.
    • Control lighting. Create separate light zones with timers, motion sensors and dimmers. This allows you to use lights only when needed or to turn them down as necessary.
  • Refrain from light trespassing. Many cities restrict light that trespasses onto a neighbor’s property or into the street. With attention to light positioning and shielding, this can easily be avoided.

Light pollution has been shown to endanger wildlife and harm human health. Navigation for wildlife becomes disoriented, and day and night are easily confused. Human circadian rhythms of wakefulness and sleep are disrupted and cancer risk is increased. Implementing smart lighting practices is a simple way to protect our health at the same time we preserve the views of the night sky.

When it comes to safety, the Chicago Alley Lighting Project discovered that when alley lighting was increased from 90-watts to 250- watts, crimes in those areas increased. Smart lighting that includes proper shielding and warmer color temperature creates a wonderful balance between safety and starlight.

Dark sky-friendly lighting is not about reducing safety or aesthetics, but about smarter practices for better health, a better environment and a chance for future generations to enjoy a view of the stars.

Author: Vicky Derksen