How dark is the sky in Piedmont?
Sky darkness for 12 towns and parks in Piedmont, worked out from NASA satellite images of light at night (2025). 7 of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Alpe Veglia and Alpe Devero Natural Park (21.45, Bortle 4), the brightest Turin (18.15, Bortle 8). Milky Way season in Piedmont runs April to August: on moonless nights the bright core stands clear of the horizon, climbing to about 17° at its highest.
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 Piedmont
- Alpe Veglia and Alpe Devero Natural ParkBortle 421.45
- Maritime Alps Nature ParkBortle 421.34
- Monviso Natural ParkBortle 421.34
- Gran Paradiso National ParkBortle 421.32
- Alta Valle Antrona Natural ParkBortle 421.31
Among the places on this site. Plenty of land between them is just as dark, with no town or park to name it by.