YozoraAtlas

How dark is the sky in Munster?

Sky darkness for 15 towns and parks in Munster, worked out from NASA satellite images of light at night (2025). 10 of them have skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Mizen Head (21.86, Bortle 3), the brightest Cork (18.37, Bortle 8). The bright core of the Milky Way never climbs clear of the horizon haze anywhere in Munster while the sky is fully dark; the rest of the band passes overhead, with the longest moonless nights from September 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 Munster with every place marked

Darkest skies in Munster

  1. Mizen HeadBortle 321.86
  2. the Kerry Dark-Sky ReserveBortle 321.83
  3. Sheep's HeadBortle 321.83
  4. Loop HeadBortle 321.78
  5. the Beara PeninsulaBortle 321.77

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 Munster

  1. CorkBortle 818.37
  2. LimerickBortle 718.45
  3. WaterfordBortle 718.78
  4. TraleeBortle 619.29
  5. EnnisBortle 619.47

All 15 places in Munster

Amber names are parks and certified dark-sky places. The figure is the Bortle class: 1 darkest, 9 city center.
Cork8Ennis6Killarney National Park4Limerick7Loop Head3Mizen Head3Sheep's Head3Tralee6Waterford7the Beara Peninsula3the Burren4the Comeragh Mountains4the Dingle Peninsula3the Galtee Mountains4the Kerry Dark-Sky Reserve3