How to Find and Evaluate a Dark Sky Site

The astronomer's worst enemy is stray light. Light pollution from improperly installed security lighting drowns out starlight, leaving little detail visible to the astronomer. Aside from a blackout, there is no cure for this situation. You can only run from it. Scroll down to Step 1 to start on your quest for that perfect patch of dark sky.


  1. Image titled Appear to Be a Vampire Step 1
    Chart the quality of your local sky. This can be done by taking an index card, folding it in half, and cutting a square out. Hold it an arm's length away and count the number of stars inside it. This number will be your guide to how much light pollution there is. Write it on the side of the card for future reference.
    • Watch the clouds. Clouds should not glow orange at night. Black clouds, almost like holes, indicate a great sky.
    • Check the weather forecast for a clear sky and for geomagnetic storms. During solar storms, auroras may come down south, and the air glow may become strikingly intense. If you live near the Northern Lights, solar storms can cause the light show to be spectacular.
  2. Image titled Capture a UFO Image on Camera Step 4
    Find the light level in your area. This can be done by going to and looking at the atlases featured on the left. Use The World Atlas of Artificial Light Sky Brightness as a guide to a site. Remember what color zone you are in.
  3. Image titled Capture a UFO Image on Camera Step 7
    Find an area that is at minimum green, preferably blue on the atlas. From these areas, you will see significant improvement over a city sky. Try traveling to a local campground in a green/blue area, because the park rangers will be able to help you get around if you get lost.
  4. Image titled Find and Evaluate a Dark Sky Site Step 4
    Travel to the site. Take the back roads because they can lead you to even better sites, but don't get lost! Have a map or GPS to guide you. When you find the site, make sure to stay away from bright lights, as this can ruin your night vision.
  5. Image titled Capture a UFO Image on Camera Step 2
    When you get there, do the star test again. If you don't see much of an improvement in the star count, go back out searching and try again. But you'll most likely see over 10 times as many stars in a good site.
    • Let your eyes adapt to the dark. Stay away from lights for 20 minutes and let your eyes do the magic. Get as far away as possible from roads.
  6. Image titled Capture a UFO Image on Camera Step 6
    Enjoy the night sky! Search for satellites, watch meteors as they streak across the sky, and catch a glimpse of the zodiacal light or air glow.
    • Take optical aid. A small telescope or binoculars will do. You'll be surprised at the wonders the sky has to offer. Try searching for the zodiacal light after sunset, which follows the sun's path across the sky. Later at night, the gegenschein and green air glow will be visible overhead. If you're lucky, you may be able to see all eight planets with binoculars, and possibly a few asteroids.
    • There are many tablet device apps and cell phone apps on astronomy that help you to pinpoint the night sky. Make sure that you're device is fully charged and use this app to help you to locate features in the night sky.


  • Use a laser to point out objects. Be careful with it though, as it may wipe your night vision, or do worse, such as damage your eyesight.
  • The worst sources of light pollution are half-cutoff (cobra) streetlights and billboards. These spray light up, not down, and wipe out starlight. These also cause severe glare, and can be a pain when watching the sky. You'll notice a great improvement if you get out of sight of streetlights.
  • Only take a red flashlight out with you. A white flashlight will reduce or wipe out your night vision. Red cellophane over the bulb is a simple but effective modification.
  • If Venus or Jupiter blind you, or you confuse the Milky Way with rising dawn, you've found the perfect site. Light pillars caused by city lighting should not be apparent at your site.
  • Take your friends with you! It's always fun to share the wonders of the universe with friends.
  • If artificial lighting is bothering you, write a letter to your city's mayor. If you are afraid to tackle this alone, the International Dark Sky Association (and possibly your local astronomy club) will be glad to help.


  • Always tell someone you are going to a dark sky site. Preferably take someone with you too and always be alert when you're alone in a quiet, lonely area.
  • Don't look at bright lights. Only 2 seconds of light are needed to ruin your night vision. It may also give you a headache, or leave afterimages that block your field of view. Not only do you need to watch the stars with your eyes, you need to keep an eye on your surroundings.
  • Prepare for the worst––take a blanket, a bit of food, and a cell phone. Make sure you have a full tank, and don't leave the car battery running too long.
  • Summer nights can still get dangerously cold, especially in the desert. Dress for the cold. Take something warm to eat, such as an MRE or ramen noodles in a thermos.
  • Don't point at airplanes or others with a laser. You could damage their eyesight. A confirmed hit on an airplane can get you fined.

Things You'll Need

  • Dark sky atlas such as The World Atlas of Artificial Light Sky Brightness
  • Index card
  • Red flashlight
  • Food and drink to keep warm
  • Warm clothing
  • Transportation

Sources and Citations

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