It’s estimated that one-third of the world’s population no longer can see the Milky Way, including 80% of Americans.

Our apparent fear of the dark is not only adding to our wasteful carbon emissions, it’s messing with a lot of wildlife.

Light pollution affects many animals because light and dark signal when to eat, sleep, hunt, migrate and reproduce.

Because most songbirds migrate at night, light pollution disrupts their circadian rhythm. Bright lights on tall buildings attract birds, which can result in fatal collisions.

Nocturnal insects, like fireflies, can have trouble finding mates.

Sea turtles lay their eggs on beaches, and when babies hatch, they move toward the brighter horizon of the ocean. However, artificial lights draw them away from the ocean, resulting in death.

More than 130 species of coral on the Great Barrier Reef spawn new life by moonlight. Urban light can disrupt their timing.

Light pollution may be contributing to drastic die-offs of nocturnal amphibians by changing both foraging and breeding patterns.

Pollination also is disrupted. In one study, nocturnal visits to plants were reduced by 62% compared to dark areas.

Trees evolved with circadian cycles to photosynthesize, send out leaves in spring and shed leaves in fall. Artificial light wreaks havoc with this system by extending the length of a day, thus changing flowering patterns and the capacity to store energy for winter.