Stargazing at National Park of Tzoumerka, Peristeri & Arachthos Gorge: when is the sky clear and dark?
August is the best month for stargazing at National Park of Tzoumerka, Peristeri & Arachthos Gorge: on average 85 clear, moonless hours of full darkness, and 57% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 57% of Europe’s land (NASA VIIRS 2025).
national park · Greece
Month by month
| Month | Nights with ≥ 2 such hours | Clear moonless dark hours | Moonless dark hours | Of them clear |
|---|---|---|---|---|
| January | 20% | 35 | 174 | 20% |
| February | 20% | 33 | 148 | 22% |
| March | 20% | 32 | 139 | 23% |
| April | 21% | 29 | 115 | 25% |
| May | 22% | 27 | 94 | 29% |
| June | 36% | 39 | 80 | 49% |
| July | 56% | 72 | 90 | 80% |
| August | 57% | 85 | 112 | 76% |
| September | 38% | 57 | 128 | 44% |
| October | 30% | 50 | 158 | 31% |
| November | 26% | 50 | 166 | 30% |
| December | 26% | 49 | 188 | 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 | 57% of Europe’s land |
|---|---|
| Light pollution | dark rural sky (darkest 20–50 %) |
| Sky-glow index (own, VIIRS) — Darkest spot we found | 2.60 |
| Sky-glow index (own, VIIRS) — at the official map point | 9.88 |
| Sky-glow index (own, VIIRS) — median across the area | 11 |
| Darkest spot we found | 39.475, 21.142 (map) — within 15 km of the Wikidata point (no 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 | 10.8 | 26% |
| 9 December 2026 | 8–9 December 2026 | 11.3 | 26% |
| 7 January 2027 | 7–8 January 2027 | 11.3 | 20% |
| 6 February 2027 | 6–7 February 2027 | 10.5 | 20% |
| 8 March 2027 | 7–8 March 2027 | 9.3 | 20% |
| 6 April 2027 | 6–7 April 2027 | 8.0 | 21% |
| 6 May 2027 | 6–7 May 2027 | 6.5 | 22% |
| 4 June 2027 | 4–5 June 2027 | 5.3 | 36% |
| 4 July 2027 | 3–4 July 2027 | 5.2 | 56% |
| 2 August 2027 | 1–2 August 2027 | 6.2 | 57% |
| 31 August 2027 | 31 August 2027 – 1 September 2027 | 7.7 | 57% |
| 30 September 2027 | 29–30 September 2027 | 9.2 | 38% |
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 | 33% | 54% | 6.2 | 71° |
| Geminids * | 13–14 December 2026 | 35% | 20% | 9.7 | 84° |
| Geminids * | 14–15 December 2026 | 35% | 28% | 8.7 | 84° |
| Quadrantids | 3–4 January 2027 | 37% | 13% | 11.0 | 65° |
| Lyrids | 22–23 April 2027 | 32% | 95% | 1.2 | 84° |
| Eta Aquariids * | 5–6 May 2027 | 40% | 0% | 7.8 | 23° |
| Eta Aquariids * | 6–7 May 2027 | 43% | 0% | 7.8 | 24° |
| Perseids * | 12–13 August 2027 | 88% | 84% | 3.0 | 65° |
| Perseids * | 13–14 August 2027 | 87% | 90% | 2.2 | 66° |
| Orionids | 21–22 October 2027 | 47% | 59% | 3.7 | 66° |
| Leonids * | 17–18 November 2027 | 33% | 82% | 1.8 | 71° |
| Leonids * | 18–19 November 2027 | 35% | 73% | 3.3 | 71° |
| Geminids | 14–15 December 2027 | 35% | 98% | 0.0 | 84° |
* 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.