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A Reserve to



Dark Sky Reserve




Continuing the efforts of numerous initiatives to fight light pollution and protect the nighttime environment, the Mont Mégantic region became the very first International Dark Sky Reserve certified by the DarkSky International in 2007.

Centered on the Mont-Mégantic National Park and Observatory, the Mont-Mégantic International Dark Sky Reserve currently measures about ​​5,300 square kilometres. In order to include the main sources of light pollution from the surrounding area, the Reserve's territory covers an area of approximately 50 km of radius around Mont Mégantic.


This includes the 14 municipalities of the Haut-Saint-François RCM to the west and 19 municipalities of the Granit RCM to the east. Located 60 km to the west, the city ​​of Sherbrooke is also part of the Dark Sky Reserve and is a very important partner.

The process leading to the designation of the International Dark Sky Reserve has contributed to the development of strong regional expertise in outdoor lighting management. The implementation of regulations for outdoor lighting and the involvement of the 34 municipalities of the Reserve strongly contributed to the adequate control and reduction of light pollution, which had greatly increased in previous decades. Thanks to the initial conversion of thousands of luminaires, light pollution at the core of the Reserve has been reduced by more than a third while saving nearly 2 gigawatt-hour of electricity per year for the region.

Following the creation of the Mont-Mégantic International Dark Sky Reserve, new reserves certified by DarkSky International have been created around the world. In addition, many cities and parks have followed the pioneering city of Flagstaff in Arizona and the Natural Bridges National Monument in Utah and are now part of the Dark Sky movement.


According to the definition given by DarkSky International, an International Dark Sky Reserve (IDSR) is a large public or private land possessing a starry sky of exceptional quality and nocturnal environment which is subject to protection for scientific, educational, cultural or natural enjoyment.


The reserve consist of a core area where the dark sky is preserved, and a peripheral area where public administrators, individuals, and businesses recognize the importance of natural darkness preservation and are committed to protecting it in the long term. DarkSky International also certifies communitiesparks, sanctuaries as well as urban dark sky places.





In the past, some regions around the world established their own certification as "Dark Sky Reserves" since there was no universal official standard based on specific criteria. In fact, before 2006, the Royal Astronomical Society of Canada (RASC) was the only organization that had a recognition program in place to acknowledge communities' efforts to reduce light pollution.


Concerned that this would affect the credibility of a real worldwide dark sky protection plan, DarkSky International put together a working committee to define and oversee "International Dark Sky Reserves", "International Dark Sky Parks" and "International Dark Sky Communities". The Mont-Mégantic region served as a model for elaborating minimum criteria to be met in order to be certified.

We can only rejoice at the growing number of certified dark sky protection locations around the world.

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Mont Mégantic




Astronomical observations on Mont Mégantic

As research, education, and tourism activities in the Mont Mégantic region are based on astronomical observation, the protection of the dark sky is of crucial importance. Unfortunately, the distance from urban centres does not guarantee dark skies by itself and light pollution at the Mont-Mégantic Observatory (OMM) had more than doubled during its first twenty years of operation.


With its constant growth, light pollution risked compromising the scientific usefulness and the vocation of OMM in the medium term. It then became imperative to curb the growth of light pollution and reduce its impacts.


Invading light

It was at the end of the 90s that the fight against light pollution really began. The OMM was then in the process of renewing its research equipment and wanted to preserve its deep sky observation capacity.

Preliminary analyzes were made to determine the approximate contributions to sky glow:

  • 50% from municipalities located within a 25km radius

  • 25% from the city of Sherbrooke

  • 25% from other light sources located more than 25km

Despite their small size, the nearby municipalities contribute a significant portion of the light pollution above the observatory since light intensity is greatly correlated with distance. Therefore, these municipalities were priority targets in reducing light pollution around the Mont-Mégantic National Park.


Starting a project to protect the stars

In 2002, the ASTROLab's president and the directors of the Mont-Mégantic National Park and the MMO jointly defined the guidelines of the light pollution reduction project.


By considering everyone's needs and in a spirit of regional collaboration, the objectives necessary for the creation of an International Dark Sky Reserve were agreed and set. Ultimately, the project would allow the preservation of the scientific research capacity and the astro-tourism potential of Mont Mégantic.


To do this, the action plan targeted three main areas of intervention:

  1. AWARENESS, to educate about the issues and solutions;

  2. REGULATION, to ensure long-term preservation;

  3. CONVERSION and retrofit of light fixtures, to reduce light pollution.



Regulations and conversions

One after another, the Granit RCM, the Haut-Saint-François RCM, and the city of Sherbrooke adopted regulations to limit light pollution and protect the starry sky with the installation of suitable outdoor lighting.

Following the adoption of the first regulations, a major phase of conversion of public and private lighting was undertaken in the municipalities located near Mont Mégantic. Together, municipalities, businesses, and citizens participated in the reduction of light pollution.


Designation of the world's first

International Dark Sky Reserve

Work carried out in this initial light pollution abatement project made it possible to convert more than 3,300 luminaires in a total of 17 municipalities. This project alone is saving more than 1,700,000 kWh per year of energy, or approximately $200,000 of electricity, for the entire region.


The results obtained to date are indisputable: with a reduction of over 35% in light pollution, the region has truly regained its stars!

On September 21, 2007, it was with great pride that the Mont Mégantic region was officially recognized by DarkSky International as the world's first International Dark Sky Reserve!

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