when it comes and how it is celebrated in the world

The equinox occurs twice a year – in spring and autumn. It marks the astronomical change of seasons.

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The autumnal equinox is considered the beginning of autumn according to the astronomical definition of the seasons.

After the autumnal equinox, the days become shorter than the nights, the sun rises later, and darkness falls earlier. This will last until the winter solstice, after which the days will gradually become longer.

In 2024, the autumnal equinox will take place on September 22 at 1:44 p.m. Kyiv time (at 12:44 p.m. GMT). The Autumnal Equinox 2024 falls on a Sunday.

Autumnal equinox: what is it

Due to the tilt of the Earth’s axis, the Sun illuminates the northern and southern hemispheres more. But twice a year (in spring and autumn) the Sun evenly illuminates them both. Then night and day become almost equal in duration, which is why this phenomenon got its name – equinox.

The equinox occurs when the sun crosses the celestial equator – an imaginary line perpendicular to the Earth’s axis that divides the planet into the northern and southern hemispheres.

On the day of the autumnal equinox in the northern hemisphere, the day is a few minutes longer than the night. Perfectly equal day and night come a few days after the “official” phenomenon and this moment is called equilux.

Such a difference is caused by the refraction of the sun’s rays by the atmosphere and the error due to the measurement of sunrise and sunset. It is usually fixed by the first and last rays on the horizon, but the Sun is not a point, but a disc. So the perfectly equal length of day and night occurs when the subsolar point (the point of the Earth located directly under the Sun) falls on the equator.

This is where you can determine the current position of the subsolar point, so you can follow it now and on the exact day of the equinox and see the difference with your own eyes.

The date of the autumnal equinox: interesting facts

According to NASA, the equinox is the best time to “catch” the northern lights, because geomagnetic activity is more active in spring and fall than in summer or winter. Considering the fact that the northern lights have already been observed several times in Ukraine, it is worth paying attention to the sky above us during the equinox.

In Japan, the autumnal equinox is an official national Higan holiday that lasts a whole week – three days before and 3 days after this astronomical phenomenon. There is even a saying: “both heat and cold end with higan”, because this holiday is celebrated for the second time during the spring equinox. Higan is also a memorial period, during which people visit the graves of their ancestors, pray, bring flowers and light incense sticks.

Neo-pagans on this day celebrate the festival of Mabon, one of the festivals of the Wiccan Wheel of the Year. On the day of the autumnal equinox, they give thanks for a bountiful harvest and for the fact that the harvested fruits will provide them with food during the winter months.

In Great Britain, on the autumnal equinox, they celebrate the harvest festival. There is also the concept of “Harvest Month”. This is the closest full moon to the equinox (within two weeks before or after the equinox). These days, the moon lingers a little longer in the sky, and it was believed that in ancient times it allowed peasants to work late in the fields to harvest crops.

The Chinese and Vietnamese still celebrate the “Harvest Month” (or Mid-Autumn Festival). It falls on the 15th day of the eighth lunar month according to the Chinese calendar (ie, in September according to the Gregorian calendar). On this day, the streets are lit up with lanterns, people gather together, have dinner, eat traditional round “Mooncakes” and watch the moon.

In Greek mythology, the autumnal equinox marks the descent of the fertility goddess Persephone into the underworld to Hades. He kidnapped her and tricked her into marriage. Mother Demeter managed to return her daughter Persephone, but with the condition that she would be forced to return underground to her husband for 3 months. So when Persephone goes to Hades, everything on earth freezes in grief.