A linear systems approach to protect the night sky: implications for current and future regulations

Area of Science:

• Astronomy and Astrophysics
• Environmental Science
• Urban Planning

Background:

• Global artificial light emissions are increasing, causing widespread skyglow and threatening astronomical observations.
• Light pollution poses risks to scientific infrastructure, biodiversity, tourism, and cultural heritage.
• Current mitigation strategies focus on individual light sources, neglecting cumulative territorial impacts.

Purpose of the Study:

• To propose a complementary mitigation strategy for light pollution based on ambient artificial skyglow immission limits.
• To establish clear limits for acceptable night sky deterioration above astronomical observatories.
• To develop a framework applicable to protecting nocturnal ecosystems and informing public lighting decisions.

Main Methods:

• Development of general indicators to quantify ambient artificial skyglow.
• Creation of linear models to correlate skyglow indicators with territorial artificial light emissions.
• Analysis of aggregated light pollution effects across regions surrounding observatories.

Main Results:

• A novel top-down strategy for setting skyglow immission limits is presented.
• Linear models demonstrate a relationship between emissions and skyglow indicators.
• The proposed approach offers a quantifiable method for managing light pollution impacts.

Conclusions:

• Ambient artificial skyglow immission limits are essential to complement existing light pollution controls.
• This strategy provides a robust tool for safeguarding astronomical observatories and nocturnal environments.
• The approach supports informed spatial planning and public lighting policies to mitigate light pollution.