In this webinar, presented live on February 15, 2023, we learned more about the best practices for protecting night skies in your community, parks, and other places.
9:00: Welcome & Introductions
9:15-9:55 - Todd Burlet, President - Starry Skies North - IDA Chapter
Todd provided an introduction to light pollution. There are four types: glare (eye sees source of light), skyglow (sum total of all wasted light that is unshielded or reflecting off of ground), light trespass (neighboring light that you don’t control but impacts you), and clutter (unshielded and haphazard).
Minnesota has the largest dark-sky area east of the Mississippi and three International Dark Sky Places: Voyageur’s National Park, Quetico Provincial Park, and the Boundary Waters Canoe Area (which is the world’s largest IDS Sanctuary, a designation for the most protected sites in the world).
Yet, 99% of Americans live under light pollution. In urban cores, only 10% of the stars are visible to people. Light pollution is a growing problem - 10% increase each year and we are doubling our light pollution every 7 years.
However, there are solutions! There are five principles for responsible outdoor lighting:
Low light levels
Color (color temperature: 3,000 kelvin or below recommended)
The ROLAN Manifesto for lighting professionals includes 10 core principles for external illumination and a plan for action to implement change in the lighting community to lead to a more sustainable, healthier, and safer future for all.
7 reasons to care about light pollution:
Energy waste: 35% of light is wasted by unshielded, poorly aimed, and poorly controlled outdoor lighting — $3 billion/year! 21 million tons of CO2 annually – 3 million passenger cars/ 600 million trees!
Awe and natural darkness: Increases social positivity, altruism, and connectedness
Wildlife & ecosystems: Light pollution effects migratory birds with disorientation and entrapment, habitat avoidance, disrupts their sleep/wake cycle, and can decrease offspring. Songbird populations have declined 40% in the last 50 years - due in part to light pollution. Meanwhile, insects are attracted to lights - bats may overeat if they are ok with light or they may suffer because certain bats avoid lighting. In water ecosystems, there can be more algae (need light to grow) but zooplankton (which eats algae) don’t like light. Melatonin and reproductive hormones are disrupted for fish and it can trigger fight or flight mode for certain fish species which expends their energy.
Astro-tourism: We are fortunate to have world-class dark skies along with iconic cultural and natural attractions that can be enjoyed day and night in Minnesota. This is great for astronomy and can help increase tourism and occupancy during shoulder seasons.
Cultural heritage: Dark skies can provide inspiration for artists and cultural storytelling. For example, many constellations have strong cultural stories tied to them that vary across cultures.
Safety and social justice: Well designed lighting can improve driver and pedestrian safety but poor design create glare and clutter that reduce safety. Lights can often provide a false sense of security. Studies show that 'omnipresence' programs disperse the community and move the crime to other locations.
Human health & wellness: Melatonin signals it is time to rest and restore but light over 3000K can disrupt our circadian rhythm and lead to cancers, obesity, diabetes, cardiovascular disease, anxiety, depression, and impaired daytime function.
The International Dark Sky Communities program provides guidance and certification for the implementation and enforcement of quality lighting policies, dark-sky education, and citizen support.
9:55-10:05 - Q&A
10:05 - 10:10 - Minnesota GreenCorps Host Site Information - Candice McElroy
Host site applications are open until March 14
10:10-10:30 - Nick Cusick, Events & Marketing Coordinator - Visit Cook County
Nick shared how astro-tourism has grown across Cook County. One opportunity is that the tourism season can be elongated by branding shoulder seasons as great dark-sky seasons (although it’s good any time of the year!). This has added recognition from media (See 25 Amazing Journey for 2022, National Geographic, Nov. 2021).
The Dark Sky Festival is held every winter since 2018 and there are many more events held throughout the year. In 2022, the festival included activities from NASA, Lonely Planet’s “Dark Skies: A Practical Guide to Astrotourism” author Valerie Stimac, and a new documentary, “Northern Nights, Starry Skies”. The 2023 Dark Sky Festival will be December 7-9.
10:30-10:50 - Kip Berglund, Senior Planner - City of Plymouth
Kip provided information about the City of Plymouth’s Exterior Lighting ordinance that was adopted in 2004 based on the joint Illuminating Engineering Society and International Dark Sky Association’s Model Lighting Ordinance (MLO). The goal was to improve lighting regulation in the city, particularly in areas where homes bordered commercial and industrial development. The City updated their ordinance in 2013 for lighting considerations related to LEDs and created a light zone map to regulate ambient lighting, set maximum lighting mount height, provide a lumens per hardscape allowance, and set maximum allowable backlight/uplight/glare ratings based on zoning locations. The ordinance also includes language on lighting controls, curfew and cutoff times, and shielding requirements.
11:00 - conclusion
View the workshop recording:
View the slides and additional materials:
- International Dark Sky Association
- Starry Skies North - Minnesota IDA Chapter
Light Pollution Map - An interactive world light pollution map using satellite data.
These Minnesota cities are winning the fight against light pollution (Star Tribune, 2022)
In an ever-brighter world, tourists travel north for truly dark skies (MPR, 2022)
How ‘dark sky’ designation are giving communities new tourism appeal (Washington Post, 2021)
Northern Nights, Starry Skies (PBS North, 2022)
The People Behind Northern Nights, Starry Skies (National Park Service)
‘Sense of awe’: Astrotourism takes off along the shores of Lake Superior (Kare 11, 2022)
Dark Skies Festival - 2022 (Explore Minnesota)
Weeklong events celebrate dark skies, battle against light pollution (Duluth News Tribune, 2022)
Top stargazing apps:
Stellarium Web and Mobile