YozoraAtlas

How dark is the sky in Akershus?

Sky darkness for 3 towns and parks in Akershus, worked out from NASA satellite images of light at night (2025). None of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Østmarka National Park (19.31, Bortle 6), the brightest Asker (17.88, Bortle 8). The bright core of the Milky Way never climbs clear of the horizon haze anywhere in Akershus while the sky is fully dark; the rest of the band passes overhead, with the longest moonless nights from October to March.

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 Akershus with every place marked

Darkest skies in Akershus

  1. Østmarka National ParkBortle 619.31
  2. LillestrømBortle 817.98
  3. AskerBortle 817.88

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 3 places in Akershus

Amber names are parks and certified dark-sky places. The figure is the Bortle class: 1 darkest, 9 city center.
Asker8Lillestrøm8Østmarka National Park6