On the Chinese lunar calendar, "Autumn Equinox" is the beginning of autumn and thisday is just at the middle point between "Autumn Begins" to "Hoar-Frost Falls". After "Autumn Equinox", the temperature decreases obviously, just like the old proverbs among the farmers, "Each autumn rain makes it's colder", "The night of White Dewsand Autumn Equinox, one night is colder than the one before". It arrives on September 22 to September 23 each year when the sun reaches the celestial longitude of 180 degrees. As said in the ancient Chinese books, "the Autumn Equinox" shows the Yin Qiand Yang Qi are half and half on this day". This means the day and night are balanced and the heat and the cold are even. There is no polar day or polar night happening on this day on every corner of the world. In some part of the north-east China, it's not strange to see frost at this time. The differences between the temperature in the morning and in the night are increasing, to more than 10 degree Celsius. The amountof rainfall decreases and it's getting drier and drier in the air.

Traditional Customs
"Spring Equinox" is the time for sacrifice for the sun and "Autumn Equinox" is the time tosacrifice for the moon. According to historical research, the original moon scarification ceremony is held on the day of "Autumn Equinox". However, since it doesn't happenson the same day each year and sometimes the moon on this day is not the roundest. Aceremony without full noon is not a perfect one. Later, the ceremony date was changed from "Autumn Equinox" to the Mid-Autumn Festival Day. In many countryside areas in China, people still have the tradition of eating Tang Yuan (rice dumpling). Apart from eating, people boil twenty to thirty Tang Yuan without filings, plug it with thin bamboostick and put it along the field. This is to "stick the mouth of sparrow", hoping the sparrows won't come to destroy the crops.

Healthy Living Tips
Based on the principle that the Yin Qi and Yang Qi are balanced on this day, people should live and eat also in a way that can balance the two inside their body. Also astemperature decreases, people should keep exercises to buid immunity. To benefiting the lungs, people can drink more water and eat food like sesame, nut, sticky rice, honey, pears and diary food.