1. International Dark-Sky Assocation Light Pollution: How Seeing the Stars will Save You Money Dr. Harold Williams Montgomery College Planetarium located at the Takoma Park/Silver Spring Campus http://montgomerycollege.edu/Departmennts/planet http://montgomerycollege.edu/Departmennts/planet

2. International Dark-Sky Assocation What Is It? The Night Around Us. –Our Communities. The Night Above Us. Dark skies.

3. International Dark-Sky Assocation The Bottom Line on “Why” For a functional, comfortable, and beautiful nighttime environment. For an environment friendly to: –humans, including the aging eye, –wildlife, –plants, –the night sky.

4. International Dark-Sky Assocation Where to light and when? Only where it is needed. –Avoid obtrusive light. –No wasted light or energy. Only when needed.

5. International Dark-Sky Assocation How much light? The myth of The More the Better. –Use IESNA or CIE recommended levels. Environmental lighting zones. –Consider the location where you are. Use good transition lighting.

6. International Dark-Sky Assocation North America at Night

7. International Dark-Sky Assocation Poor security lighting, using an old fashion 175 watt mercury fixture

8. International Dark-Sky Assocation Almost a definition of light trespass, at an installation in San Francisco.

9. International Dark-Sky Assocation Glare from a walkway light.

10. International Dark-Sky Assocation Glare, luminance overload, bad transition lighting

11. International Dark-Sky Assocation Why so much bad lighting ? Lack of awareness. –Even in the lighting community. –Builders, contractors, owners, operators. –The public. Governmental staff. Apathy, or inertia.

12. International Dark-Sky Assocation Keys to Quality Lighting See the effect, not the source. Shine the light down. No glare! Light only where and when needed. Don’t over light. Use energy efficient sources.

13. International Dark-Sky Assocation Use of a full cutoff fixture for a parking lot

14. International Dark-Sky Assocation A good antique (or period lighting) fixture, full cutoff

15. International Dark-Sky Assocation Here is another good example, using lighting fixtures with good control of the light output.

16. International Dark-Sky Assocation So … It works, right? It’s common sense. Use only good lighting! Let’s fix the bad stuff! Educate everyone; build allies.

17. International Dark-Sky Assocation Some Other Issues Visibility Safety and security The aging and disabled eye Human health, and animals and plants. Energy We all win!

18. International Dark-Sky Assocation IDA The International Dark-Sky Association Newsletter. Information sheets. Images. Slides. CD’s, videos, and so on. Web site: www.darksky.orgwww.darksky.org Join IDA ! We need you.

19. International Dark-Sky Assocation IDA’s Goals To preserve and protect the nighttime environment and our heritage of dark- skies through quality outdoor lighting. Membership based. Over 10,000 members, from all the states and 70 other countries. 500 organizations.

20. International Dark-Sky Assocation International Dark-Sky Association 3225 N First Avenue Tucson AZ 85719 USA 520-293-3198 Fax: 520-293-3192 ida@darksky.org www.darksky.org