Less than 100 years ago, everyone could look up and see a spectacular starry night sky. Now, millions of children across the globe will never experience the Milky Way where they live.
The increased and widespread use of artificial light at night is not only impairing our view of the universe, it is adversely affecting our environment, our safety, our energy consumption and our health.
What is Light Pollution?
Most of us are familiar with air, water, and land pollution, but did you know that light can also be a pollutant?
The inappropriate or excessive use of artificial light – known as light pollution – can have serious environmental consequences for humans, wildlife, and our climate. Components of light pollution include:
Glare – excessive brightness that causes visual discomfort
Skyglow – brightening of the night sky over inhabited areas
Light trespass – light falling where it is not intended or needed
Clutter – bright, confusing and excessive groupings of light sources
Image by Anezka Gocova, in “The Night Issue”, Alternatives Journal 39:5 (2013)
Light pollution is a side effect of industrial civilization. Its sources include building exterior and interior lighting, advertising, commercial properties, offices, factories, streetlights, and illuminated sporting venues.
The fact is that much outdoor lighting used at night is inefficient, overly bright, poorly targeted, improperly shielded, and, in many cases, completely unnecessary. This light, and the electricity used to create it, is being wasted by spilling it into the sky, rather than focusing it on to the actual objects and areas that people want illuminated.
How Bad is Light Pollution?
With much of the Earth’s population living under light-polluted skies, over lighting is an international concern. If you live in an urban or suburban area all you have to do to see this type of pollution is go outside at night and look up at the sky.
According to the 2016 groundbreaking “World Atlas of Artificial Night Sky Brightness,” 80 percent of the world’s population lives under skyglow. In the United States and Europe 99 percent of the public can’t experience a natural night!
Before and during the 2003 Northeast US blackout, a massive power outage that affected 55 million people. Photo by Todd Carlson
If you want to find out how bad light pollution is where you live, use these free tools:
An interactive map created from the”World Atlas”
The NASA Blue Marble Navigator for a bird’s eye view of the lights in your town.
Google Earth overlay also created from the “World Atlas” data.