Dark Sky Odds

Stargazing at Nacionalni park "Sutjeska": when is the sky clear and dark?

August is the best month for stargazing at Nacionalni park "Sutjeska": on average 60 clear, moonless hours of full darkness, and 42% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 80% of Europe’s land (NASA VIIRS 2025).

Data updated: 31 December 2025 · Sources and licences

Calculated 5 November 2026 · cloud cover ERA5 2006–2025 · night lights NASA VIIRS 2025

national park · Bosnia and Herzegovina

AugustBest month
425Clear moonless dark hours a year
80%darker than … of Europe’s land
42%Nights with ≥ 2 such hours (August)

Month by month

MonthNights with ≥ 2 such hoursClear moonless dark hoursMoonless dark hoursOf them clear
January14%2517214%
February17%2714818%
March18%3113823%
April22%2810626%
May19%228227%
June24%256141%
July38%447559%
August42%6010358%
September29%4312634%
October26%4415728%
November23%3816922%
December23%3818720%

Climate, not a forecast: these are shares of past nights (ERA5 reanalysis, 2006–2025), not a prediction for a particular night. Check a forecast before you go.

Light pollution

Darker than80% of Europe’s land
Light pollutiondark rural sky (darkest 20–50 %)
Sky-glow index (own, VIIRS) — Darkest spot we found0.63
Sky-glow index (own, VIIRS) — at the official map point0.78
Sky-glow index (own, VIIRS) — median across the area0.71
Darkest spot we found43.308, 18.742 (map) — within 2.8 km of the Wikidata point (no OSM boundary)

Next new moons

New moonNightMoonless dark hours that nightTypical share of good nights that month
9 November 20268–9 November 202610.823%
9 December 20268–9 December 202611.523%
7 January 20277–8 January 202711.514%
6 February 20276–7 February 202710.517%
8 March 20277–8 March 20279.318%
6 April 20276–7 April 20277.722%
6 May 20276–7 May 20275.819%
4 June 20274–5 June 20274.324%
4 July 20273–4 July 20274.238%
2 August 20271–2 August 20275.542%
31 August 202731 August 2027 – 1 September 20277.342%
30 September 202729–30 September 20279.029%

Hours with the Sun below −18° and the Moon below the horizon, on the night of the new moon, at the darkest spot.

Meteor showers

ShowerPeak nightChance of a clear peak nightMoon litMoonless dark hours (Sun < −12°)Radiant max. height
Leonids17–18 November 202630%55%6.368°
Geminids *13–14 December 202632%20%10.080°
Geminids *14–15 December 202628%28%9.080°
Quadrantids3–4 January 202718%13%11.367°
Lyrids22–23 April 202737%95%1.281°
Eta Aquariids *5–6 May 202738%0%7.320°
Eta Aquariids *6–7 May 202733%0%7.219°
Perseids *12–13 August 202770%84%3.066°
Perseids *13–14 August 202773%90%2.067°
Orionids21–22 October 202742%59%3.563°
Leonids *17–18 November 202730%82%1.868°
Leonids *18–19 November 202735%73%3.268°
Geminids14–15 December 202728%98%0.080°

* The peak falls in daylight in Europe, so both neighbouring nights are shown.

Clear peak night: at least 2 hours with ≤ 20 % cloud while the Sun is below −12°, on the same calendar night ± 1 in 2006–2025.

How we calculate