To assess whether the sky in your area is affected by light pollution, follow these steps:
Visual Observation: On a clear night, look at the stars. In a heavily light-polluted area, you’ll see fewer stars due to the brightness of artificial lights drowning out dimmer celestial objects. In urban regions, it’s common to see only the brightest stars, planets, and the moon.
Bortle Scale: Utilize the Bortle Scale, a nine-level numeric scale that measures the night sky’s brightness and clarity, ranging from Class 1 (excellent dark-sky site) to Class 9 (inner-city sky). If your area falls between Classes 7 to 9, it indicates significant light pollution.
Dark Sky Maps and Apps: Online resources and mobile apps can show light pollution levels globally. Websites like Light Pollution Map or apps such as “Stellarium” can provide insights and help you identify your specific location’s conditions.
Gauging Naked-Eye Limiting Magnitude: Identify how faint stars you can observe with the naked eye. Comparing this with a star chart can provide an empirical measure of light pollution in your area.
Check for Nearby Light Sources: Consider the presence of nearby artificial light sources like streetlights, advertising signs, and large buildings with exterior lighting, which can significantly contribute to local light pollution.
Community and Local Resources: Contact local amateur astronomy clubs or observatories. They can offer insight into local observing conditions and may even conduct dark sky assessments.
By combining these methods, you can determine the extent to which light pollution affects the viewing of the night sky in your area.