Tang Chik (冬至)

I spent this morning down at the Swee Cheok Tong, offering worship to our Kongsi deities in observance of Tang Chik (冬至), the Winter Solstice. I had assumed it would fall tomorrow, on the 22nd of December, but the calendar told me otherwise. As I drove into the city, the signs were already there: other Chinese clan houses along the way had their doors open as different communities carried out their own rituals.

Tang Chik marks the winter solstice, the point in the year when the day is shortest and the night longest. In traditional Chinese society, this was no ordinary date. In agrarian times, farmers would lay down their tools and return home, recognising that the agricultural year had reached a pause. Families gathered not to mark an ending, but a turning. Of course, we are no longer farmers here in the nanyang, but the significance of the day remains the same. The eating of koay ee symbolised the idea of growing a year older, not necessarily wiser, but certainly marked by time.

Unlike many traditional festivals tied to the lunar calendar, Tang Chik is governed by astronomy. It occurs when the sun reaches a specific point in its apparent path across the sky, the moment when Earth’s axial tilt places the sun at its lowest position in the Northern Hemisphere. This astronomical alignment produces the longest night of the year. In Chinese cosmology, Tang Chik is one of the 24 Solar Terms, fixed not by human convention but by the movement of the heavens.

This year, in 2025, the winter solstice occurs on the 21st of December, with the precise astronomical moment falling at 15:03 GMT. Converted to Malaysian time, which is eight hours ahead, this places the solstice at 11:03pm on the night of the 21st. On the surface, this would seem to justify observing Tang Chik on that same date.

However, I would argue that this conclusion is not entirely consistent with traditional Chinese timekeeping. In the classical Chinese luni-solar system, the transition from one day to the next does not occur at midnight, but at 11pm. Time is divided into twelve two-hour segments, each beginning on an odd hour. The hour which runs from 11pm to 1am marks the start of a new day.

Viewed through this traditional framework, a solstice occurring at 11:03pm would already fall into the following day. By that reckoning, the moment of Tang Chik in Malaysia actually belongs to the 22nd of December rather than the 21st. From a strictly astronomical standpoint, both interpretations may appear reasonable. Yet within the logic of traditional Chinese calendrical thinking, celebrating Tang Chik on the 22nd would be entirely consistent.

Because the Earth’s orbit and axial tilt follow a predictable rhythm, the winter solstice falls on nearly the same date each year, usually between the 21st and 22nd of December, and occasionally on the 23rd. This consistency is why Tang Chik remains one of the rare traditional observances that aligns neatly with the Gregorian calendar. The other, of course, is Cheng Beng.

Standing in the clan house this morning, surrounded by incense and the familiar faces of the Kongsi members, it struck me that Tang Chik is less about marking a moment in time than acknowledging a shift. The longest night has passed. The days will lengthen again, slowly and almost imperceptibly at first, but the turning has already begun.