Dark Sky Odds

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

March is the best month for stargazing at Valkmusa National Park: on average 29 clear, moonless hours of full darkness, and 18% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 55% 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

MarchBest month
128Clear moonless dark hours a year
55%darker than … of Europe’s land
18%Nights with ≥ 2 such hours (March)

Month by month

MonthNights with ≥ 2 such hoursClear moonless dark hoursMoonless dark hoursOf them clear
January6%101895%
February7%101437%
March18%2911126%
April7%83125%
May0%00—
June0%00—
July0%00—
August2%21219%
September13%189120%
October15%2414816%
November7%111746%
December9%162048%

No astronomical darkness (May, June, July): 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 than55% of Europe’s land
Light pollutiondark rural sky (darkest 20–50 %)
Sky-glow index (own, VIIRS) — Darkest spot we found2.82
Sky-glow index (own, VIIRS) — at the official map point3.52
Sky-glow index (own, VIIRS) — median across the area3.47
Darkest spot we found60.575, 26.675 (map) — within 2.5 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 202611.07%
9 December 20268–9 December 202612.39%
7 January 20277–8 January 202712.56%
6 February 20276–7 February 202710.77%
8 March 20277–8 March 20278.318%
6 April 20276–7 April 20274.37%
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 20270.02%
31 August 202731 August 2027 – 1 September 20273.32%
30 September 202729–30 September 20277.713%

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 202610%54%7.551°
Geminids *13–14 December 202615%20%12.062°
Geminids *14–15 December 202612%28%10.562°
Quadrantids3–4 January 202715%13%14.274°
Lyrids *22–23 April 202737%96%1.559°
Lyrids *23–24 April 202732%90%3.258°
Eta Aquariids *5–6 May 202728%0%2.2-6°
Eta Aquariids *6–7 May 202717%0%1.8-7°
Perseids *12–13 August 202728%84%3.359°
Perseids *13–14 August 202733%90%2.361°
Orionids21–22 October 202718%59%1.845°
Leonids *17–18 November 202710%83%0.351°
Leonids *18–19 November 20278%73%2.251°
Geminids14–15 December 202712%98%0.062°

* 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