Equinox
The moment at which the Sun crosses the celestial equator. In March it marks the start of astronomical spring, in September the start of autumn. In 2027 spring begins on 20 March at 21:25.
What is the equinox?
Twice a year the Sun, on its path along the ecliptic, crosses the celestial equator. In March it moves from the southern to the northern side, in September back again. These two moments are called the equinox, from the Latin aequinoctium, equal night. On these days the Sun rises almost exactly in the east and sets in the west, everywhere on Earth.
The point in the sky where the Sun stands in March is called the vernal point, the one in September the autumnal point. With the equinox in March astronomical spring begins in the northern hemisphere, with the one in September autumn.
Are day and night really the same length?
Almost. At the equinox the day in Central Europe is already a little longer than the night. The day counts from the first to the last ray of sunshine. The air lifts the image of the Sun at the horizon slightly, and the upper edge of the disc can already be seen before its centre rises.
In Berlin on 20 March 2027 the day lasts 12 hours and 9 minutes, the night 11 hours and 51 minutes. There, day and night are the same length around 18 March and around 26 September.
In front of which constellation does the Sun stand?
At the March equinox the Sun stands in front of the constellation Pisces, in September in front of Virgo. In the zodiac signs of astrology, Aries begins at the vernal point. Because the vernal point moves backwards through the constellations through the precession of the Earth’s axis, sign and constellation today lie almost a whole constellation apart. More on this under zodiac.
The biodynamic planting calendar works with the constellations, that is, sidereally. There the vernal point determines neither the constellation nor the day type.
The equinox in the biodynamic year
In the Dyyna calendar the equinox is recorded as an event in the sky. For sowing and planting on this day, what the constellation, the Moon’s course and the Moon’s phase say applies; there is no rule of its own. In the biodynamic course of the year the equinoxes, together with the solstices and the festivals, divide the year. More under biodynamic festival calendar.
Dates up to 2030
| Year | Start of spring | Start of autumn |
|---|---|---|
| 2026 | – | 23 Sep, 2:06 CEST |
| 2027 | 20 Mar, 21:25 CET | 23 Sep, 8:02 CEST |
| 2028 | 20 Mar, 3:17 CET | 22 Sep, 13:45 CEST |
| 2029 | 20 Mar, 9:01 CET | 22 Sep, 19:37 CEST |
| 2030 | 20 Mar, 14:51 CET | 23 Sep, 1:27 CEST |
The date shifts by just under six hours from year to year and jumps back by a day in a leap year, because the calendar year is not exactly as long as the Earth’s orbit.
Sources
- Equinox, Wikipedia
- March equinox, Wikipedia
- Solstices and Equinoxes: 2001 to 2100, Fred Espenak, AstroPixels
Frequently asked questions about the equinox
When does spring begin in 2027?
On 20 March 2027 at 21:25 CET. Autumn begins on 23 September 2027 at 8:02 CEST.
What is the difference between the astronomical and the meteorological start of spring?
Astronomical spring begins with the equinox in March. Weather services count in whole months, and their spring begins on 1 March.
Does spring always begin on 20 or 21 March?
In this century it falls in Central Europe on 19, 20 or 21 March. Up to 2030 it falls on 20 March every year.
What is the vernal point?
The point at which the Sun crosses the celestial equator from south to north at the start of spring. Today it lies in the constellation Pisces.