Stargazing at Defileul Jiului National Park: when is the sky clear and dark?
October is the best month for stargazing at Defileul Jiului National Park: on average 43 clear, moonless hours of full darkness, and 25% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 65% of Europe’s land (NASA VIIRS 2025).
national park · Romania
Month by month
| Month | Nights with ≥ 2 such hours | Clear moonless dark hours | Moonless dark hours | Of them clear |
|---|---|---|---|---|
| January | 20% | 34 | 182 | 19% |
| February | 17% | 24 | 145 | 17% |
| March | 20% | 30 | 136 | 22% |
| April | 16% | 21 | 103 | 20% |
| May | 8% | 10 | 74 | 14% |
| June | 11% | 13 | 62 | 21% |
| July | 18% | 21 | 65 | 33% |
| August | 27% | 35 | 98 | 36% |
| September | 23% | 33 | 126 | 26% |
| October | 25% | 43 | 155 | 28% |
| November | 17% | 31 | 168 | 18% |
| December | 23% | 38 | 188 | 20% |
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 | 65% of Europe’s land |
|---|---|
| Light pollution | dark rural sky (darkest 20–50 %) |
| Sky-glow index (own, VIIRS) — Darkest spot we found | 1.67 |
| Sky-glow index (own, VIIRS) — at the official map point | 2.85 |
| Sky-glow index (own, VIIRS) — median across the area | 2.22 |
| Darkest spot we found | 45.258, 23.442 (map) — within 6.6 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 | 17% |
| 9 December 2026 | 8–9 December 2026 | 11.5 | 23% |
| 7 January 2027 | 7–8 January 2027 | 11.5 | 20% |
| 6 February 2027 | 6–7 February 2027 | 10.5 | 17% |
| 8 March 2027 | 7–8 March 2027 | 9.3 | 20% |
| 6 April 2027 | 6–7 April 2027 | 7.5 | 16% |
| 6 May 2027 | 6–7 May 2027 | 5.3 | 8% |
| 4 June 2027 | 4–5 June 2027 | 3.7 | 11% |
| 4 July 2027 | 3–4 July 2027 | 3.5 | 18% |
| 2 August 2027 | 1–2 August 2027 | 5.0 | 27% |
| 31 August 2027 | 31 August 2027 – 1 September 2027 | 7.2 | 27% |
| 30 September 2027 | 29–30 September 2027 | 9.0 | 23% |
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 | 28% | 54% | 6.5 | 66° |
| Geminids * | 13–14 December 2026 | 45% | 20% | 10.2 | 78° |
| Geminids * | 14–15 December 2026 | 43% | 28% | 9.0 | 78° |
| Quadrantids | 3–4 January 2027 | 40% | 13% | 11.5 | 69° |
| Lyrids | 22–23 April 2027 | 35% | 95% | 1.2 | 78° |
| Eta Aquariids * | 5–6 May 2027 | 18% | 0% | 7.0 | 18° |
| Eta Aquariids * | 6–7 May 2027 | 22% | 0% | 7.0 | 18° |
| Perseids * | 12–13 August 2027 | 60% | 84% | 3.2 | 67° |
| Perseids * | 13–14 August 2027 | 63% | 90% | 2.2 | 68° |
| Orionids | 21–22 October 2027 | 45% | 59% | 3.3 | 61° |
| Leonids * | 17–18 November 2027 | 28% | 83% | 1.7 | 66° |
| Leonids * | 18–19 November 2027 | 25% | 73% | 3.0 | 66° |
| Geminids | 14–15 December 2027 | 43% | 98% | 0.0 | 78° |
* 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.