Human produced light pollution not only inhibits our view of the stars; poor lighting threatens astronomy, disrupts ecosystems, affects human circadian rhythms, and wastes energy to the tune of $2.2 billion per year in the U.S. alone.
One way astronomy is affected:
Unshielded lights send their light in all directions, including straight up. This sets the sky aglow, in much the same way that the sun sets the sky aglow during the day. Now, the sky does not glow as bright at night as it does during the day, but the increase in sky glow caused by cities is enough to make it difficult to see dim objects in the sky... and it's getting worse.
One way ecosystems are affected:
Newly hatched turtles need a dark night sky to orient themselves toward the sea, but artificial lights behind beaches lure them away. Hatchlings are attracted to lights and crawl inland, or crawl aimlessly down the beach, sometimes until dawn, when terrestrial predators or birds get them.
One way humans are affected:
Light tresspass has been implicated in disruption of the human (and animal) circadian rhythm, and strongly suspected as the cause of suppressed melatonin production, depressed immune systems, and increase in cancer rates such as breast cancer.
Making a difference -
In 2003, Jennifer Barlow, a sophomore from Midlothian, VA, founded a grassroots effort called National Dark Sky Week "because I want people to be able to see the wonder of the night sky without the effects of light pollution. The universe is our view into our past and our vision into the future. With National Dark Sky Week, I want to help preserve its wonder."
It has been endorsed by the International Dark Sky Association, American Astronomical Society, Astronomical League, and Sky and Telescope, and now goes by the title of International Dark Sky Week.
The most important goal is that we once again may be able to see the wonder of the universe that has been a treasured part of history as long as humans have existed on this Earth, and that we do not allow such beauty to fade behind a blanket of light pollution.
The opportunity to experience the natural night sky should be available to everyone. This natural resource, which inspires our attempts to understand the cosmos, should be protected through the use of well-designed lighting systems that put light where it is needed and not waste energy through unnecessary illumination of the sky. Properly designed lighting systems provide safety and convenience without polluting one of our greatest natural assets.
It is so important that International Dark Sky Week gains more and more support each year to ensure its success. The only way to reduce light pollution is if everyone participates.
Ideas for participation:
- Evaluate your lighting needs and extinguish all unnecessary lighting in or around your property. If lights are necessary (for safety or visibility) do not turn them off.
- Blog about it. Or write a letter to your local news source to increase publicity.
- Encourage your friends and neighbors to permanently reduce the use of non-essential lighting. Purchase and install a dark sky friendly lighting fixture for yourself or a neighbor. Or talk to your local supplier about carrying a selection of these fixtures.
- If your an educator, teach students about the night sky and light pollution. Kids can find ways to understand and improve the issue by participating in activities such as a star count or a home audit.
- Host a observing event this weekend, such as a family/neighborhood backyard stargazing party, picnic, BBQ, or sidewalk astronomy.
- Spread the news to everyone you know and encourage them to turn off their unneccesary lights.
- Whatever you do, and however you participate, have fun and enjoy the night sky.
The night sky has been forgotten by many. I hope that International Dark Sky Week will encourage you to "look up" and appreciate its wondrous features... And not just nights this week, but on any night.