Search any location or drop a pin to see its Bortle sky-darkness class — estimated from real satellite sky-brightness data. Built for planning where to shoot the Milky Way.
A 1-to-9 scale astronomers use to describe how dark a night sky is. Lower is darker and better for seeing faint objects like the Milky Way.
Aim for Bortle 4 or darker
The Milky Way's core is usually visible to the naked eye by Bortle 4, and genuinely striking by Bortle 3 or better. In Bortle 5-6 you can often still capture it with a camera even when it's hard to see by eye.
Check the moon phase too
A bright moon washes out faint sky detail just like light pollution does. Dark skies and a new moon together give you the best shot at seeing the Milky Way's full structure.
Terrain and weather still matter
This map estimates sky glow from satellite data — it can't see local terrain blocking your horizon, incoming clouds, or a single bright streetlight right next to your spot. Use it to narrow down a region, then verify in person if you can.
Small distances can make a big difference
Driving even 20-30 minutes away from a town's direct glow often drops you a full Bortle class or more. Zoom in and drop a few pins around your planned spot to compare.
A 1-to-9 scale astronomers use to describe how dark a night sky is, from Bortle 1 (an excellent truly dark site where the Milky Way casts visible shadows) to Bortle 9 (inner-city skies where only the Moon, planets, and a handful of bright stars are visible).
The underlying data comes from the World Atlas of Artificial Night Sky Brightness, a satellite-derived model of sky glow. It's a genuinely useful planning tool, but actual darkness at a specific spot also depends on terrain, weather, moon phase, and nearby direct light sources a satellite can't fully see — treat the number here as a strong estimate, not a lab measurement.
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The core is usually visible to the naked eye by Bortle 4 and becomes genuinely striking by Bortle 3 or darker. In Bortle 5-6 suburban skies you can often still capture it with a camera even when it's hard to see by eye.