Dark Sky Odds

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

December is the best month for stargazing at Urho Kekkonen National Park: on average 18 clear, moonless hours of full darkness, and 10% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 71% 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 · Finland

DecemberBest month
84Clear moonless dark hours a year
71%darker than … of Europe’s land
10%Nights with ≥ 2 such hours (December)

Month by month

MonthNights with ≥ 2 such hoursClear moonless dark hoursMoonless dark hoursOf them clear
January8%141967%
February8%111378%
March12%147519%
April0%00—
May0%00—
June0%00—
July0%00—
August0%00—
September3%3398%
October9%131359%
November6%111826%
December10%182059%

No astronomical darkness (April, May, June, July, August): the Sun stays above −18° all night.

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 than71% of Europe’s land
Light pollutiondark rural sky (darkest 20–50 %)
Sky-glow index (own, VIIRS) — Darkest spot we found1.18
Sky-glow index (own, VIIRS) — at the official map point6.03
Sky-glow index (own, VIIRS) — median across the area4.04
Darkest spot we found68.242, 28.125 (map) — within 15 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 202611.26%
9 December 20268–9 December 202613.210%
7 January 20277–8 January 202713.08%
6 February 20276–7 February 202710.78%
8 March 20277–8 March 20277.012%
6 April 20276–7 April 20270.00%
6 May 20276–7 May 20270.00%
4 June 20274–5 June 20270.00%
4 July 20273–4 July 20270.00%
2 August 20271–2 August 20270.00%
31 August 202731 August 2027 – 1 September 20270.00%
30 September 202729–30 September 20275.83%

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 202613%54%8.744°
Geminids *13–14 December 202620%20%14.355°
Geminids *14–15 December 202615%28%12.255°
Quadrantids3–4 January 202713%13%15.570°
Lyrids *22–23 April 2027—96%0.0—
Lyrids *23–24 April 2027—90%0.0—
Eta Aquariids *5–6 May 2027—1%0.0—
Eta Aquariids *6–7 May 2027—0%0.0—
Perseids *12–13 August 2027—84%0.0—
Perseids *13–14 August 2027—90%0.0—
Orionids21–22 October 202722%59%0.038°
Leonids *17–18 November 202713%83%0.044°
Leonids *18–19 November 202717%73%0.344°
Geminids14–15 December 202715%98%0.055°

* 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