End of Heat

Meaning

The End of Heat, Chushu, is the fourteenth of the twenty-four solar terms: the Sun at 150°, about 23 August. Chǔ here means to stop, to withdraw into rest: the heat of summer goes back where it came from. The middle of the day can still be hot, but the mornings and evenings cool, the sky rises high and clear, and the nights lengthen visibly.

It is a principal term, the middle of the Monkey month, and it names the seventh lunar month. In the north this is the time between the storms of summer and the first harvests of autumn, when the grain fills and colours in the fields.

Its three pentads show the season growing stern: the hawk lays out the birds it has caught, as the otter laid out its fish in spring; heaven and earth begin to grow austere; and the grain ripens. The old readers saw in it the first sign of autumn’s strictness, the time to gather in and to put in order.

In practice

• In BaZi nothing turns at the End of Heat: the month pillar stays the Monkey month’s until Bailu. A birth near it is no nearer a change of pillar.
• In the Chinese calendar it names the seventh lunar month.
• The Calendar marks it on its day, with the Sun at 0° Virgo, as the middle of the Monkey month; astrology marks the same instant as the Sun’s entry into Virgo.
• In the zodiac and Feng Shui the month animal and the month’s star are those of the Monkey month, from Liqiu to Bailu.

Across traditions

• In Western astrology the Sun enters Virgo at this very moment, the maiden who holds an ear of wheat in her hand, the star Spica, as the Chinese calendar says that the grain ripens.
• In Korea an old saying holds that after cheoseo the mosquitoes’ mouths go crooked, so cool have the nights become; in Japan the term is shosho, in Vietnam xử thử.
• In the farming year of Europe the late August weeks are those of the grain harvest’s end and the first fruits, the same turn from heat to gathering.

Origin and history

The Monthly Ordinances of the Book of Rites already give the signs of this month, the hawk’s offering and the austerity of heaven and earth, and tell the ruler to mend the dykes and the city walls against the autumn floods. The Huainanzi, in 139 BC, sets the term among the twenty-four, and the old seasonal instructions give each sign its five days.

The term has fewer festivals than its neighbours, being a time of work, but it marks a change that every farming family felt: from here the long labour of the harvest begins. In some regions families share a duck dish in these days, and in many the evenings are given back to walks under the clear autumn sky.

How Ulune calculates it

Ulune takes the End of Heat as the instant the Sun’s apparent longitude reaches 150°, from its table of the solar terms computed with the Swiss Ephemeris for 1800 to 2200. As a principal term it changes no pillar; the Calendar shows it on the reader’s own date. In 2026 it fell on 23 August at 02:18 UT.

Correspondences