Stargazing at Central Balkan National Park: when is the sky clear and dark?
August is the best month for stargazing at Central Balkan National Park: on average 57 clear, moonless hours of full darkness, and 40% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 69% of Europe’s land (NASA VIIRS 2025).
national park · Bulgaria
Month by month
| Month | Nights with ≥ 2 such hours | Clear moonless dark hours | Moonless dark hours | Of them clear |
|---|---|---|---|---|
| January | 28% | 50 | 183 | 27% |
| February | 27% | 41 | 143 | 29% |
| March | 26% | 40 | 138 | 29% |
| April | 25% | 34 | 109 | 31% |
| May | 16% | 20 | 84 | 23% |
| June | 17% | 18 | 62 | 29% |
| July | 34% | 40 | 76 | 52% |
| August | 40% | 57 | 103 | 56% |
| September | 34% | 52 | 128 | 41% |
| October | 32% | 53 | 155 | 34% |
| November | 30% | 49 | 168 | 29% |
| December | 27% | 48 | 184 | 26% |
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 than | 69% of Europe’s land |
|---|---|
| Light pollution | dark rural sky (darkest 20–50 %) |
| Sky-glow index (own, VIIRS) — Darkest spot we found | 1.35 |
| Sky-glow index (own, VIIRS) — at the official map point | 2.27 |
| Sky-glow index (own, VIIRS) — median across the area | 1.90 |
| Darkest spot we found | 42.792, 24.492 (map) — within the OSM boundary |
Next new moons
| New moon | Night | Moonless dark hours that night | Typical share of good nights that month |
|---|---|---|---|
| 9 November 2026 | 8–9 November 2026 | 10.7 | 30% |
| 9 December 2026 | 8–9 December 2026 | 11.5 | 27% |
| 7 January 2027 | 7–8 January 2027 | 11.5 | 28% |
| 6 February 2027 | 6–7 February 2027 | 10.7 | 27% |
| 8 March 2027 | 7–8 March 2027 | 9.3 | 26% |
| 6 April 2027 | 6–7 April 2027 | 7.7 | 25% |
| 6 May 2027 | 6–7 May 2027 | 5.8 | 16% |
| 4 June 2027 | 4–5 June 2027 | 4.5 | 17% |
| 4 July 2027 | 3–4 July 2027 | 4.3 | 34% |
| 2 August 2027 | 1–2 August 2027 | 5.7 | 40% |
| 31 August 2027 | 31 August 2027 – 1 September 2027 | 7.5 | 40% |
| 30 September 2027 | 29–30 September 2027 | 9.0 | 34% |
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
| Shower | Peak night | Chance of a clear peak night | Moon lit | Moonless dark hours (Sun < −12°) | Radiant max. height |
|---|---|---|---|---|---|
| Leonids | 17–18 November 2026 | 43% | 54% | 6.3 | 68° |
| Geminids * | 13–14 December 2026 | 42% | 20% | 9.8 | 80° |
| Geminids * | 14–15 December 2026 | 43% | 28% | 8.8 | 80° |
| Quadrantids | 3–4 January 2027 | 47% | 13% | 11.3 | 67° |
| Lyrids | 22–23 April 2027 | 52% | 95% | 1.2 | 81° |
| Eta Aquariids * | 5–6 May 2027 | 22% | 0% | 7.5 | 21° |
| Eta Aquariids * | 6–7 May 2027 | 22% | 0% | 7.3 | 20° |
| Perseids * | 12–13 August 2027 | 80% | 84% | 3.0 | 66° |
| Perseids * | 13–14 August 2027 | 80% | 90% | 2.0 | 66° |
| Orionids | 21–22 October 2027 | 57% | 59% | 3.5 | 63° |
| Leonids * | 17–18 November 2027 | 43% | 83% | 1.8 | 68° |
| Leonids * | 18–19 November 2027 | 42% | 73% | 3.0 | 68° |
| Geminids | 14–15 December 2027 | 43% | 98% | 0.0 | 80° |
* 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.