Artificial Light at Night (ALAN)

Artificial Light at Night (ALAN) refers to human-made lighting used during nighttime hours, such as streetlights, billboards, and illuminated buildings. While ALAN enhances safety and activity after dark, excessive or poorly managed lighting can disrupt natural ecosystems, interfere with wildlife behaviors, and impact human health by disturbing circadian rhythms. It also contributes to light pollution, which obscures views of the night sky. Understanding ALAN involves balancing the benefits of nighttime illumination with its environmental and health effects by implementing smarter lighting practices, such as using appropriate fixtures, reducing brightness, and directing lights downward to minimize waste and negative impacts.