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What is light pollution?

Answer: The human-made alteration of outdoor light levels from those occurring naturally. Learn more


What causes light pollution?


Who and what are affected by light pollution?


What can we do about light pollution?


Spread the word

Resources you can use to teach policy makers, businesses, and the general public about light pollution.

Public outreach materials

Educational brochures, presentations, infographics, and more. Download or order printed copies.

Materials for educators

Easily downloaded lesson plans for teachers and educational activities for kids.

Family activities to enjoy the night from home

Ways to engage in the dark sky movement with your loved ones — in your backyard, through your living room window, or on a computer screen.


Light pollution solutions

What renters can do

Renters don’t have as much flexibility as property owners to change their outdoor lighting, but we have some advice for renters and apartment complexes.

My neighbor’s lighting

What you can do when a neighbor installs a new, unshielded light on their property that spills onto your property and perhaps even inside your home. This is known as light trespass.

Guidance for U.S. homeowners associations (HOAs)

Few HOAs include outdoor lighting requirements in their covenants, conditions, and restrictions (CC&Rs). DarkSky has approved model CC&Rs that are dark sky friendly.

You’re part of the solution!

People just like you are already involved in the global dark sky movement! You can be part of the solution too.


The science of outdoor lighting

Artificial Light at Night (ALAN) research literature database

The ALAN database (off-site link) provides references to scientific literature on all aspects of research into artificial light at night, a joint effort between DarkSky and the Loss of the Night Network.

Measuring light pollution

Solving light pollution requires data, and a great way to do that is to measure the brightness of the night sky. It’s relatively easy to make such measurements, and you can help!

How to conduct a night sky quality survey

You don’t need to be a scientist to study light pollution! Surveys using sky quality meters (SQMs) are one way we can collect data on our brightening skies.


Dark sky principles

The Five Principles for Responsible Outdoor Lighting

By incorporating these principles, properly designed electric lighting at night can be beautiful, healthy, and functional.

Values-centered outdoor lighting

A resolution by DarkSky’s board of directors that expands on The Five Principles for Responsible Outdoor Lighting.

Responsible Outdoor Lighting at Night (ROLAN) manifesto for lighting

By following the ROLAN manifesto, governments, businesses, and individuals can support the implementation of the United Nations sustainable development goals.


Lighting policy and ordinances

Lighting ordinances

How to identify whether your community has an outdoor lighting ordinance, how to advocate for an ordinance, and how to ensure that an ordinance is enforced.

Dark sky friendly outdoor lighting for policy makers

Why municipalities should be concerned about light pollution.

Guidance for U.S. homeowners associations (HOAs)

Few HOAs include outdoor lighting requirements in their Covenants, Conditions, and Restrictions (CC&Rs). DarkSky has approved model CC&Rs that are dark sky friendly.

Lighting zones

The five lighting zones, LZ0 through LZ4, reflect the base (or ambient) light levels desired by a community, and are used when writing legislation for light pollution.

Model Lighting Ordinance

The MLO provides suggested lighting ordinance language and is designed to help municipalities develop outdoor lighting standards that reduce glare, light trespass, and sky glow. 



“Losing the Dark” planetarium film

A free planetarium show introducing and illustrating some of the issues around light pollution and suggesting three simple actions people can take to help mitigate it. Available in many formats and languages.


A collection of videos about dark sky issues.

DarkSky on YouTube

Videos from our staff, Advocates, and more. This is also where you can find recordings of DarkSky virtual events such as our annual Under One Sky global conference.


Informational images that can help people understand the complex issues of light pollution. Free downloads.


FAQs and Glossary

DarkSky FAQs

Do you have a question about light pollution, outdoor lighting, or what DarkSky does? Then check out our Frequently Asked Questions page.

FAQs about International Dark Sky Places

Everything you need to know about applying for Dark Sky Place certification and our nocturnal conservation program.


What’s an angstrom? Or the cut off angle of a luminaire? Actually, what’s a luminaire anyway?! Our Glossary unlocks lighting industry and light pollution terms!


DarkSky publications


Our award-winning members-only magazine provides current news about DarkSky and night sky protection and in-depth articles on DarkSky programs, light pollution issues, and protecting the night sky.

Annual impact reports

Our annual reports quantify the impact of our work around the globe, ranging from success stories and stats to financials.

Press releases and reports

Keep up to date with the latest news and scientific research.

Find or start a DarkSky chapter

Our chapter members are on the ground making a difference in their neighborhoods and communities. Find a chapter in your area and get involved. No chapter nearby? Then find some like-minded folks and start one!