Dark Sky Odds

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

March is the best month for stargazing at Sallandse Heuvelrug National Park: on average 32 clear, moonless hours of full darkness, and 21% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 24% 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 · Netherlands

MarchBest month
196Clear moonless dark hours a year
24%darker than … of Europe’s land
21%Nights with ≥ 2 such hours (March)

Month by month

MonthNights with ≥ 2 such hoursClear moonless dark hoursMoonless dark hoursOf them clear
January12%1918210%
February16%2314716%
March21%3213025%
April18%218226%
May6%62227%
June0%00—
July0%1610%
August10%137217%
September19%2411421%
October14%2215315%
November15%2117512%
December10%151888%

No astronomical darkness (June): 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 than24% of Europe’s land
Light pollutionnoticeable light glow
Sky-glow index (own, VIIRS) — Darkest spot we found10
Sky-glow index (own, VIIRS) — at the official map point11
Sky-glow index (own, VIIRS) — median across the area12
Darkest spot we found52.325, 6.408 (map) — within the OSM boundary

Next new moons

New moonNightMoonless dark hours that nightTypical share of good nights that month
9 November 20268–9 November 202610.815%
9 December 20268–9 December 202612.010%
7 January 20277–8 January 202711.812%
6 February 20276–7 February 202710.716%
8 March 20277–8 March 20279.021%
6 April 20276–7 April 20276.518%
6 May 20275–6 May 20273.26%
4 June 20274–5 June 20270.00%
4 July 20273–4 July 20270.00%
2 August 20271–2 August 20272.510%
31 August 202731 August 2027 – 1 September 20276.010%
30 September 202729–30 September 20278.319%

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 202623%55%6.860°
Geminids *13–14 December 202618%20%10.871°
Geminids *14–15 December 202620%28%9.771°
Quadrantids3–4 January 202723%13%12.572°
Lyrids22–23 April 202740%95%1.570°
Eta Aquariids *5–6 May 202735%0%5.710°
Eta Aquariids *6–7 May 202730%1%5.59°
Perseids *12–13 August 202725%84%3.267°
Perseids *13–14 August 202723%90%2.267°
Orionids21–22 October 202730%58%2.854°
Leonids *17–18 November 202723%82%1.560°
Leonids *18–19 November 202722%73%2.860°
Geminids14–15 December 202720%98%0.071°

* 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