1 of 12
Ian Cheney, Filmmaker
Credit: The City Dark/Wicked Delicate Films
The bright lights in many cities block all the stars in a hazy glow, as seen in this still from the new documentary "The City Dark."
2 of 12
Tribute in Light
Credit: The City Dark/Wicked Delicate Films
Light pollution is so common that hardly any stars are visible in many cities around the world.
3 of 12
Observatory in "City Dark" Movie
Credit: The City Dark/Wicked Delicate Films
Astronomers have been forced to go farther and farther afield to find dark enough skies.
4 of 12
Birds Killed by Light Pollution
Credit: The City Dark/Wicked Delicate Films
Migrating birds can become disoriented by brightly lit buildings at night, causing many of them to crash into walls.
5 of 12
Observatory Interior from "City Dark" Movie
Credit: The City Dark/Wicked Delicate Film
Some of the best night skies are found in extremely remote locations, far from any city lights.
6 of 12
Brooklyn Streetlight in "City Dark" Documentary
Credit: The City Dark/Wicked Delicate Films
The documentary "The City Dark" explores what happens to people and animals when the stars are no longer visible at night.
7 of 12
Observatory in Hawaii from "City Dark" Documentary
Credit: The City Dark/Wicked Delicate Films
The filmmakers behind "The City Dark" travel to some of the few spots left on the globe with pristine views of the sparkling night sky.
8 of 12
Skywatching Attempt in Times Square
Credit: The City Dark/Wicked Delicate Films
Frustrated skywatchers in big cities may find it hard to spot even a single star from some brightly-lit locales.
9 of 12
Arizona Sky Village
Credit: The City Dark/Wicked Delicate Films
Some people, such as residents of the dark-sky community Arizona Sky Village, are choosing to live as far from city lights as possible.
10 of 12
Trespassing Light
Credit: The City Dark/Wicked Delicate Films
There is some evidence that exposure to bright lights at night may lead to increased cancer rates.
11 of 12
New York City, Capital of Light Pollution
Credit: The City Dark/Wicked Delicate Films
New York City is one of the most light-polluted spots on an increasingly over-lit Earth.
12 of 12
Light Pollution Can Harm Sea Turtles
Credit: The City Dark/Wicked Delicate Films
Light pollution from seaside buildings can confuse newborn sea turtles who have only a short time to make it to the ocean after hatching on the beach.
