Looking up at the starry night sky is one of my favorite pastimes. I love picking out the few constellations that I know and can see in the sky like the big dipper, little dipper and Orion’s belt.
I have only seen the milky way once in my life and it was when I was about 15 years old, and had travelled very far north (into the countryside) for an overnight trip. The sky was so pure and untainted. I have never forgotten how full and luminous it looked on that night.
It might surprise you to learn that artificial lighting actually obstructs our view of the galaxy through pollution. When artificial outdoor lighting becomes wasteful, annoying, and needless, it is known as light pollution. Many environmentalists, naturalists, and medical researchers consider light pollution to be one of the fastest growing and most inescapable forms of pollution.
In fact, more than 1/3 of the human population cannot see the milky way at night due to light pollution.
More than one half the European population has lost the ability to see the milky way.
2/3 of the US population has lost the ability to see the milky way.
None of this is to say that electric light is extremely bad. Artificial light has benefited society by; extending the length of the productive day, offering more time not just for working, and extending the life of recreational activities.
The effects of artificial lighting might not seem like a big deal to you. But what if I were to tell you that this artificial lighting can also increase your chances of cancer…yeah, I thought that might grab your attention.
Types of Light Pollution
Sky glow is the result of artificial lights raising the night sky’s luminescence and creating the most visible effect of light pollution. Sky glow appears as a bright halo over urban areas at night. It is a product of light being scattered by water droplets or particles in the air.
Light trespass occurs when unwanted artificial light from, for instance, a floodlight or streetlight spills onto a neighboring property, lighting an area that would otherwise be dark.
Glare is created by light that shines horizontally.
Over illumination refers to the use of artificial light well beyond what is required for a specific activity, such as keeping the lights on all night in an empty office building.
You’re probably wondering when these artificial light nuisances become a health hazard. Well Dr. Richard Stevens, a professor and cancer epidemiologist at the University of Connecticut Health Center, believes that light photons must hit the retina for biologic effects to occur. In an environment where there is a lot of artificial light at night, (like Manhattan, Chicago, Las Vegas, or LA) there is a larger opportunity for your retina’s to be exposed to these harmful photons.
It is not only night owls who receive these photons as almost everyone awakes during the night and unless you have blackout shades, artificial light sneaks through your window.
George Brainard, a professor of neurology at Jefferson Medical College, at Thomas Jefferson University in Philadelphia says, “The health effects of light pollution have not been as well defined for humans as for wildlife, although a compelling amount of epidemiological evidence points to a consistent association between exposure to indoor artificial nighttime light and health problems such as breast cancer. Controlled laboratory studies do show that exposure to light during the night can disrupt circadian and neuroendocrine physiology, thereby accelerating tumor growth.”
What To Do About It
The best solution is to decrease your exposure to artificial lighting. Buy blackout shades, or a sleep mask for your bedroom to keep unwanted harmful rays out while you are sleeping. Use candles or other forms of natural light as often as possible instead of flicking a switch. Let your eyes adjust to the darkness instead of reaching for a flashlight or lamp.