Go Dark Sky

A light-pollution check for your address

What is light pollution hiding from your sky?

About 80% of North Americans can no longer see the Milky Way from home. Enter your ZIP and find out where you stand — and how to get your stars back.

See what light pollution took. Then go dark sky.

Why your sky looks like this

Skyglow: light spilled into the night air

Light pollution is artificial light scattered into the night atmosphere — astronomers call the result skyglow. It's growing faster than population, and it has already erased the Milky Way for most people in North America.

But unlike almost every other kind of pollution, it disappears the instant the light is fixed.

How to get your sky back

Light pollution isn't permanent.

Skyglow comes from light sent upward and outward — unshielded fixtures, and cool, blue-rich light that scatters most in the atmosphere. The fix is straightforward:

  • Fully shielded fixtures that direct light down, where it's needed
  • Warm color temperatures (3000K or below)
  • Only as much light as the task needs
  • Timers and controls so light is off when no one's there

Shielded, warm-toned fixtures send light down where it belongs — not up into the sky. Better lighting saves energy, improves visibility, and brings back stars.

See dark-sky-friendly lighting →

Methodology & data

Sky brightness is estimated from NASA's VIIRS Black Marble nighttime-lights data and translated to the Bortle scale. Visibility reflects typical clear, moonless conditions. Real conditions vary with weather, the Moon, and your horizon. Ground-truth observations: GLOBE at Night.

Credits: NASA VIIRS Black Marble science team · GLOBE at Night (NSF NOIRLab) · DarkSky International · Built by Westgate Manufacturing.

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Most people have never seen their own night sky.

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