Date: February 7, 2011

Title: Hey, Light, Get Off of My Lawn!

Podcaster: Rob Sparks, Connie Walker, Carmen Austin (as Jenny), Chris Dunlop (as Mr. Jennings), and Britny Delp (as Barb) of the NOAO EPO group. Also starring Chuck Dugan (as the Dark Skies Crusader).

Organization: National Optical Astronomy Observatory (NOAO) –

Links: & Look for us on facebook and twitter.

Description: With half of the world’s population now living in cities, many urban dwellers have never experienced the wonderment of pristinely dark skies and maybe never will. This loss, caused by light pollution, is a concern on many fronts: safety, energy conservation, cost, health and effects on wildlife, as well as our ability to view the stars. Even though light pollution is a serious and growing global concern, it is one of the easiest environmental problems people can address on local levels. In this podcast, super hero, Dark Skies Crusader, helps Jenny, Mom, Barb and Mr. Jennings, learn about the effect of light pollution on not being able to sleep and gives a simple solution. More information is discussed on the effects of light pollution on human health in general. And to provide opportunities for public involvement in dark skies preservation and energy conservation, we invite the public to participate in the GLOBE at Night campaign (

Bio: Podcast co-author, Connie Walker (as the Mom and Narrator #2), is an associate scientist and senior science education specialist in the Education and Public Outreach (EPO) group at the National Optical Astronomy Observatory (NOAO) in Tucson, Arizona. She directs the worldwide citizen science campaign on monitoring sky brightness called GLOBE at Night ( She also chaired the global cornerstone project on Dark Skies Awareness for the International Year of Astronomy ( Podcast co-author, Rob Sparks (as the Narrator #1), is a science education specialist in the EPO group at NOAO and works on the Galileoscope project (, providing design, dissemination and professional development. He also pens a great blog at New to portraying podcast characters, Carmen Austin (as Jenny), Chris Dunlop (as Mr. Jennings), and Britny Delp (as Barb) are University of Arizona undergraduates who work to support programs, events and other efforts as part of the NOAO EPO group. The returning star by popular demand is Chuck Dugan (as Dark Skies Crusader), a public program specialist for the NOAO Kitt Peak Visitor Center.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by David Zimmerman. I heard a couple of podcasts that were sponsored by ‘no one’. I hate to hear Pamela so sad, so buy a day and keep her from crying. I wonder if next year, it’ll be “366 Days of Astronomy”.


Narrator #1 (in the style of a Saturday movie serial) : It’s a typical day at Elmwood Elementary school. Ms. (or Mr.) Jennnings fifth grade science class is completing a lesson on astronomy.

Jennings: So you can see from the pictures of Mars, that there is a network of what appear to be ancient riverbeds indicating Mars once has water on it surface. Can anyone give me some other evidence that Mars once had surface water?

Jenny: Loud, long yawn

Sound effect : class bell

Jennings: All right class, read pages 35 – 40 for tomorrow and we will talk about the asteroid belt. Johnny, could I see you for a minute?

Jenny: Yes, Mr. Jennings.

Jennings: Jenny, you have been very tired in class recently. I always see you yawning and it looks like you are about to fall asleep. Your grades have started slipping as well. Is everything all right?

Jenny: I have had a lot of trouble sleeping recently. I don’t know why.

Jennings: Have you been to the doctor recently?

Jenny: Yes, he said I was healthy.

Jennings: Well, I am going to call your parents. They need to know what is going on.

Narrator: That night after dinner…

Sound effect: Dishes clanking

Jenny: Mom, may I be excused to go outside and look at the Moon with my Galileoscope? Mr. Jennings said we get extra credit if we report our observations.

Mom: Jenny, Honey, could I talk to you for a minute?

Jenny: But I want to go outside and play.

Mom: Jenny, this is important. I got a call from your teacher today. He said you have been very tired and falling asleep in class. Have you been staying up reading comic books again?

Jenny: No, I swear! You took away the flashlight! I have not been able to get to sleep. I really am trying.

Mom: The doctor couldn’t find anything wrong with you. I wonder what could be happening?

Sound effect: Doorbell

Mom: I wonder who that could be this time of night.

Dark Skies Crusader: Greetings typical suburban family.

Mom and Jenny: Dark Skies Crusader!

DSC: I am investigating reports of an increase in sleeping disorders. Is anyone in your household having difficulty sleeping?

Jenny: I am. I got in trouble at school today for falling asleep in science class.

DSC: I think I know why. Come outside with me.

Sound effect: Footsteps

DSC: Your neighbor across the street recently installed some bright new security lights.

Mom: Wow! That light is pointing right at our house!

Jenny: Look, it’s shining right into my window!

DSC: Yes, and too much nighttime lighting can interfere with human sleep patterns. It hinders production of melatonin.

Mom: What can we do?

DSC: Let’s talk to your neighbor.

Sound effect: Footsteps/doorbell/door opening

DSC: Are you the owner of this lovely ranch home?

Barb: Yes, I am.

DSC: Your new security light is shining into windows of the house across the street. Johnny is having trouble sleeping because of too much light.

Barb: But I need the lights in my garden to keep people from stealing my collection of antique sundials.

DSC: Don’t worry, friend. I think I can help both of you. All it takes is a slightly different lighting fixture.

Sound effect: Construction sounds

Jenny: Wow! You directed all the light into his garden. It no longer is shining in my window!

Barb: And there is a lot less glare now. I can see my garden even better than before. No one is going to dare take my sundials!

DSC: And I put in a lower wattage bulb since you are no longer lighting up such a large area. You should save money in the long run and you are no longer guilty of light trespass!

Jenny: And without the bright light in my yard, I can see a lot more stars with my Galileoscope!

Narrator: A few weeks later at school…

Jennings: And that is why Pluto is now considered a dwarf planet.

Sound effect: Bell

Jennings: Okay, class. Read pages 88-93 for tomorrow and we are going to learn about the telescopes at Kitt Peak National Observatory. Jenny, can I see you for a minute?

Jenny: Yes Mr. Jennings?

Jennings: I noticed your work has really improved the last couple of weeks and you don’t seem nearly as tired.

Jenny: Yes! We got a visit form the Dark Skies Crusader. He taught me about light trespass and how lighting can affect our sleep patterns. I am sleeping better now. Better yet, I can see more stars outside and have decided I want to be an astronomer when I grow up.

Narrator #1: Join us next time as the Dark Skies Crusader continues in his ongoing quest to keep the night skies safe for the next generation of astronomers!
Narrator #2:


Artificial light has benefited society by extending the workday or providing more time for recreation. However, when artificial outdoor light becomes inefficient, overused, wasted and annoying, it becomes light pollution. Many environmentalists and medical researchers consider light pollution to be one of the quickest growing forms of environmental pollution. And scientific research either shows or strongly indicates that light pollution can have adverse effects on human health.


Blue light, especially at night, can cause more eyestrain and fatigue than other colors of light and may cause halos around objects because the blue light makes it harder for the eye to focus. Just as blue light scatters in the atmosphere making our sky and oceans appear blue, it scatters in our eyes as well, impairing our night vision.

The aging eye is especially vulnerable to eyestrain and loss of night vision. With age, we undergo a natural process that reduces our visual abilities. Issues of contrast, glare, the uniformity of illumination, and the type of light used are all factors that help determine how well we see. Smart lighting decisions help preserve vision and promote the overall health of the eye.


Bright points of light from poorly designed roadway lighting produce a condition known as “disability glare”. Disability glare is so intense, it causes us to avert our eyes from the veil of light being scattered across our retinas. This reduces our sensitivity to contrast and color perception. This condition can temporarily cast everything except the light source into virtual invisibility. Older drivers are especially vulnerable to disability glare, because the aging eye loses its ability to adjust quickly to changing levels of illumination. Fully shielded roadway lighting reduces this hazard and creates a safe and more pleasant driving experience by distributing the light evenly and shielding glare from the light source.


The 24-hour day/night cycle, known as the circadian clock, affects physiologic processes in almost all living organisms. These processes include brain wave patterns, hormone production (such as melatonin), cell regulation and other biological activities. Disruption of these rhythms can result in insomnia, depression, cancer and cardiovascular disease1.


Melatonin, a naturally occurring hormone produced by the pineal gland, is known for helping to regulate the body’s daily biologic clock or circadian rhythm. Melatonin triggers a host of biologic activities, possibly including a nocturnal reduction in the body’s production of estrogen. The body produces melatonin at night, and melatonin levels drop precipitously in the presence of artificial or natural light. Numerous studies suggest that decreasing nocturnal melatonin production levels increases an individual’s risk of developing cancer.

Reduction or elimination of light at night can help maintain a robust melatonin rhythm. While any kind of light can interfere with melatonin production, the blue light is the most potent for melatonin suppression in humans.


Exposure to the artificially extended daytime of our lighted modern world can lead to de-synchronization of our internal rhythms. According to the National Institution of Health or NIH, a shift in our clocks impairs our ability to sleep and wake at the appropriate times and leads to a decrease in cognition and motor skills.
A good night’s sleep helps reduce weight gain, stress, depression and the onset of diabetes. The NIH believes humans function best when they sleep at night and act in the daytime. If outdoor light is shining into your window and disrupting your sleep, the International Dark-Sky Association or IDA recommends you block out the light or request that the light be shielded for everyone’s benefit.


The scientific community is studying the range and complexity of circadian disruption and the role of melatonin suppression from too much artificial light at night. Scientists are finding an undisputed connection between sufficient sleep and good health. Moreover, they are recognizing the importance of exposure to daylight during the day and darkness at night to maintain a routine circadian rhythm. The World Health Organization now lists “shift-work that involves circadian disruption” as a probable carcinogen.

In June 2009, the American Medical Association adopted a resolution that supports the reduction of light pollution and glare and advocates for use of energy efficient, fully shielded outdoor lighting. Ongoing research continues to probe the connection between natural darkness and human health.


The International Dark Sky Association or IDA recommends the following solutions to these issues:
• Shield and lower the wattage of all outdoor lighting for homeowners, businesses and cities in general.
• Use only the light you need, when and where you need it, to get the job done.
• Use timers, dimmers and sensors to darken unoccupied areas. Shut off the lights when you can.
• Keep your bedroom as dark as possible by using blackout curtains or dark, thick curtains when sleeping.

A shielded light requires less wattage and saves everyone money, reduces our energy use and shrinks our carbon footprint. Work with your neighbors and local government to keep the light on the ground and the skies naturally dark. This is a win-win situation for everyone. You save money, energy, and health while preserving a valuable natural resource. (See also IDA’s brochures on the effects of light pollution on energy, safety and wildlife: The text for the informational part of this podcast is adapted from 4th IDA brochure, this one on “Light Pollution and Human Health”.

Look for the IDA Fixture Seal of Approval to make sure you are buying a true dark sky friendly fixture. The IDA website ( provides recommendations for fixtures to buy.

This episode of the Dark Skies Crusader has been brought to you by the GLOBE at Night campaign, an education and public outreach program of the National Optical Astronomy Observatory in partnership with ESRI, GLOBE, and the International Dark-Sky Association.

The GLOBE at Night program is an international citizen-science campaign to raise public awareness of the impact of light pollution by encouraging everyone everywhere to measure local levels of night sky brightness and contribute their observations online to a world map. All it takes is a few minutes to participate between 8–10 pm from February 21 through March 6 and again March 22 through April 4. Your measurements will make a world of difference. For more information, visit the GLOBE at Night website at Links to references used in this podcast along with a transcript of this podcast will be available at

This has been your host, Connie Walker, along with my colleagues, Rob Sparks, Carmen Austin, Chris Dunlop, Britny Delp and Chuck Dugan, wishing you clear and dark night skies.


1 Chepesiuk, Ron. “Missing the Dark: Health Effects of Light Pollution.” Environmental Health Perspectives. Vol. 117, Num. 1, 2009.

2 Mead, M. Nathaniel, “Benefits of Sunlight: A Bright Spot for Human Health,” Environmental Health Perspectives, 116:A160–A167, 2008.

3 Straif, K., et al., “Carcinogenicity of shift-work, painting, and fire-fighting” Lancet Oncol. Vol. 8, Is. 12 pp. 1065-1066, 2007.

End of podcast:

365 Days of Astronomy
The 365 Days of Astronomy Podcast is produced by the Astrosphere New Media Association. Audio post-production by Preston Gibson. Bandwidth donated by and wizzard media. Web design by Clockwork Active Media Systems. You may reproduce and distribute this audio for non-commercial purposes. Please consider supporting the podcast with a few dollars (or Euros!). Visit us on the web at or email us at Until tomorrow…goodbye.