YozoraAtlas

How dark is the sky in Solothurn?

Sky darkness for Thal Nature Park (20.84, Bortle 4), so far the only place in Solothurn on Yozora Atlas, worked out from NASA satellite images of light at night (2025). Milky Way season in Solothurn runs May to July: on moonless nights the bright core stands clear of the horizon, climbing to about 14° at its highest.

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 Solothurn with every place marked

Darkest skies in Solothurn

  1. Thal Nature ParkBortle 420.84

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 1 place in Solothurn

Amber names are parks and certified dark-sky places. The figure is the Bortle class: 1 darkest, 9 city center.