How dark is the sky in Nevada?
Sky darkness for 26 towns and parks in Nevada, worked out from NASA satellite images of light at night (2025). 16 of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Humboldt-Toiyabe National Forest (21.92, Bortle 2), the brightest Las Vegas (16.61, Bortle 8).
19
Bortle class, 1 pristine to 9 city center
park or dark-sky place
city
Numbers like 21.95 or 16.97 are the brightness of the sky overhead on a clear, moonless night, in mag/arcsec². The scale runs backwards: a lower number means a brighter sky, from about 22 for a natural sky to about 17 in a city center.
How the readings are made
Darkest skies in Nevada
- Humboldt-Toiyabe National ForestBortle 221.92
- Black Rock Desert - High Rock Canyon Emigrant Trails National Conservation AreaBortle 221.91
- Great Basin National ParkBortle 221.91
- Berlin-Ichthyosaur State ParkBortle 221.90
- Belmont Courthouse State Historic ParkBortle 321.89
Among the places on this site. Plenty of land between them is just as dark, with no town or park to name it by.
All 26 places in Nevada
Amber names are parks and certified dark-sky places. The figure is the Bortle class: 1 darkest, 9 city center.
Avi Kwa Ame National Monument4Basin and Range National Monument3Belmont Courthouse State Historic Park3Berlin-Ichthyosaur State Park2Black Rock Desert - High Rock Canyon Emigrant Trails National Conservation Area2Carson City7Cathedral Gorge State Park4Cave Lake State Park3Enterprise8Fort Churchill State Historic Park4Gold Butte National Monument4Great Basin National Park2Henderson8Humboldt-Toiyabe National Forest2Inyo National Forest3Lake Tahoe State Park4Las Vegas8North Las Vegas8Paradise8Reno8Spring Mountains National Recreation Area5Spring Valley8Sunrise Manor8Toiyabe National Forest4Valley of Fire State Park4Ward Charcoal Ovens State Historic Park3