Astronomical Seasons 2026/2027: All Dates & Explanation

By Alexander Merz · Published on 31 August 2026 · Details checked on 14 September 2026

Why do we have seasons?

Not because of the distance to the Sun – in January the Earth is actually closest to it! The reason is the 23.4-degree tilt of the Earth’s axis: in the northern summer the northern hemisphere leans towards the Sun (high Sun, long days), in winter it leans away. In the southern hemisphere everything runs the other way round.

The four astronomical turning points

Spring and autumn equinoxes: The Sun stands straight above the equator, day and night are roughly the same length everywhere, and the Sun rises exactly in the east. Summer and winter solstices: The Sun reaches its highest or its lowest midday position – the longest day (about 16.5 hours in Germany) or the longest night.

Dates for 2026 and 2027

Source: astronomical calculation (timeanddate.de). The meteorological seasons always start on the first of the month (1 March, 1 June, 1 September, 1 December) – a convention used for weather statistics.

Equinox 2026: autumn begins on 23 September

In 2026 the autumn equinox falls on 23 September at 02:05 CEST – in the middle of the night, so the astronomical autumn begins while most people are asleep. At that moment the Sun stands exactly above the celestial equator and moves from the northern to the southern half of the sky. From now on, nights in the northern hemisphere are longer than days – until the winter solstice on 21 December.

Day and night are still not exactly equal on that day. The atmosphere lifts the Sun’s image slightly at the horizon, and sunrise is counted from the upper edge of the solar disc, not its centre. Both add a few minutes to the day. The date on which day and night really are the same length therefore comes a few days after the autumn equinox in central Europe – and a few days before the spring equinox.

There is no “autumn solstice”, even though people often search for it: solstices are only the two extremes in June and December. In spring and autumn it is the equinox. For the night sky, the start of autumn means one thing above all: the nights get longer quickly, and from October it is properly dark early in the evening again.

What the seasons mean for stargazers

Every season has its own night sky: the Winter Hexagon around Orion, the Spring Triangle with Arcturus and the constellation Leo, the Summer Triangle with Vega, and the Great Square of Pegasus in autumn. For deep-sky fans the long, dark nights around the winter solstice are the most productive time – around the summer solstice, by contrast, it never gets properly astronomically dark in Germany. All constellations at a glance.

Frequently asked questions

When is the equinox in 2026?

Twice: in spring on 20 March 2026 at 15:46 CET and in autumn on 23 September 2026 at 02:05 CEST. In 2027 they fall on 20 March (21:24 CET) and 23 September (08:01 CEST).

Is there an autumn solstice?

No. Solstices are only the highest and lowest position of the Sun in June and December. Autumn begins with the equinox – in 2026 on 23 September at 02:05 CEST.

When is the winter solstice in 2026 and 2027?

In 2026 on 21 December at 21:50 CET, in 2027 on 22 December at 03:42 CET. After that the days get longer again.

When does spring start in 2026?

Astronomically on 20 March 2026 at 15:46 CET – the exact moment of the equinox.

Why doesn’t summer always start on 21 June?

The year lasts 365.24 days – that makes the date drift between 20 and 21 June, and leap years pull it back into place.

What is the difference between the astronomical and the meteorological start of a season?

Astronomically the exact position of the Sun counts (equinox/solstice); meteorologically it is whole calendar months, for the sake of the statistics – always starting on the first of the month.

Why is July the warmest month when the solstice is in June?

Soil and oceans store heat and release it with a delay – the temperature peak lags a few weeks behind the Sun’s highest point.