YozoraAtlas

How dark is the sky in Maine?

Sky darkness for 9 towns and parks in Maine, worked out from NASA satellite images of light at night (2025). 8 of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Baxter State Park (21.88, Bortle 3), the brightest Portland (18.38, 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

NASA satellite night-lights map of Maine with every place marked

Darkest skies in Maine

  1. Baxter State ParkBortle 321.88
  2. Katahdin Woods and Waters National MonumentBortle 321.86
  3. Quoddy Head State ParkBortle 321.72
  4. Camden Hills State ParkBortle 421.45
  5. Popham Beach State ParkBortle 421.35

Among the places on this site. Plenty of land between them is just as dark, with no town or park to name it by.

Brightest city skies in Maine

  1. PortlandBortle 818.38

All 9 places in Maine

Amber names are parks and certified dark-sky places. The figure is the Bortle class: 1 darkest, 9 city center.
Acadia National Park4Baxter State Park3Camden Hills State Park4Fort Point State Park4Katahdin Woods and Waters National Monument3Pemaquid Archeological Site4Popham Beach State Park4Portland8Quoddy Head State Park3