How can light pollution be minimized?

• A. Using broadly focused lighting with minimal shielding.
• B. Using directional, shielded LED lighting.
• C. Leaving all exterior lights on all night.
• D. Increasing light intensity at the perimeter.

Answer: (B)

Reducing light pollution comes down to directing light only where it’s needed and keeping it from spilling into the night sky. Directional, shielded lighting does exactly that: it points illumination downward onto the target area (walkways, entrances, landscaping) and the shielding blocks light from escaping upward or sideways. This reduces skyglow and glare while still providing adequate visibility, and LEDs offer efficient, controllable lighting that can run at lower intensities.

By contrast, broadly focused lighting with little shielding wastes light in many directions, including upward toward the sky, which increases light pollution. Leaving exterior lights on all night keeps unnecessary illumination going, boosting light pollution and energy use. Increasing light intensity at the perimeter adds more light into the environment, worsening glare and skyglow.