Natural darkness is one of our natural resources, and it's at risk. Overused and badly used artificial outdoor lights can obscure the stars and threaten ecosystems that need both day and night. Light pollution can also affect humans by increasing the chance of sleep disorders, depression and other health issues.
Organizations like DarkSky International are working to protect star views by certifying lands where outdoor lights are managed or minimized. They certify them as Dark Sky Parks, Sanctuaries, Reserves or Communities or as Urban Night Sky Places.
Use our list of the best dark sky towns and other places in the U.S. to find incredible views of the night sky. Before you go, make sure the area is open to the public (some lands are private, and some places are only open seasonally). Check for conditions like road closures and bad weather, too. Visit first during the day to spot things that might make you trip or fall in the darkness, and be aware of local wildlife. Then go back to your stargazing site at least 30 minutes before nightfall so your eyes have time to adjust. Bring a red light so you can look around without disrupting your night vision. Don't forget a telescope or powerful binoculars.
Before you go, pick up a star map or download an astronomy app like SkyView, Stellarium Mobile, SkySafari 7 Pro or Night Sky. Night Sky is available only for iOS.
Want to help preserve dark skies? Get involved.
Shown here: A ranger at Rocky Mountains National Park using a laser to point out the constellations.