Dark Sky Odds

Stargazing at Olympos National Park: when is the sky clear and dark?

December is the best month for stargazing at Olympos National Park: on average 63 clear, moonless hours of full darkness, and 34% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 49% 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 · Greece

DecemberBest month
594Clear moonless dark hours a year
49%darker than … of Europe’s land
34%Nights with ≥ 2 such hours (December)

Month by month

MonthNights with ≥ 2 such hoursClear moonless dark hoursMoonless dark hoursOf them clear
January32%5417731%
February30%4714632%
March30%4913935%
April29%3911434%
May23%299430%
June26%297042%
July42%549060%
August42%6211056%
September33%5112740%
October33%5715636%
November32%5916835%
December34%6318734%

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 than49% of Europe’s land
Light pollutionnoticeable light glow
Sky-glow index (own, VIIRS) — Darkest spot we found3.77
Sky-glow index (own, VIIRS) — at the official map point4.66
Sky-glow index (own, VIIRS) — median across the area4.60
Darkest spot we found40.108, 22.342 (map) — within 3.6 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 202610.732%
9 December 20268–9 December 202611.334%
7 January 20277–8 January 202711.332%
6 February 20276–7 February 202710.730%
8 March 20277–8 March 20279.530%
6 April 20276–7 April 20278.029%
6 May 20276–7 May 20276.323%
4 June 20274–5 June 20275.226%
4 July 20273–4 July 20275.042%
2 August 20271–2 August 20276.242%
31 August 202731 August 2027 – 1 September 20277.742%
30 September 202729–30 September 20279.233%

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 202643%54%6.270°
Geminids *13–14 December 202650%20%9.883°
Geminids *14–15 December 202647%28%8.883°
Quadrantids3–4 January 202760%13%10.864°
Lyrids22–23 April 202743%95%1.284°
Eta Aquariids *5–6 May 202742%0%7.722°
Eta Aquariids *6–7 May 202752%0%7.723°
Perseids *12–13 August 202770%84%3.065°
Perseids *13–14 August 202775%90%2.066°
Orionids21–22 October 202753%59%3.766°
Leonids *17–18 November 202743%82%2.070°
Leonids *18–19 November 202748%73%3.270°
Geminids14–15 December 202747%98%0.083°

* 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