How dark is the sky in Trnava Region?
Sky darkness for 4 towns and parks in Trnava Region, worked out from NASA satellite images of light at night (2025). 1 of them has skies of Bortle 4 or darker, where the Milky Way shows overhead. The darkest is Dunajské luhy Protected Landscape Area (20.79, Bortle 4), the brightest Trnava (18.76, Bortle 7). Milky Way season in Trnava Region runs May to July: on moonless nights the bright core stands clear of the horizon, climbing to about 13° 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
All 4 places in Trnava Region
Amber names are parks and certified dark-sky places. The figure is the Bortle class: 1 darkest, 9 city center.
