Pear blossom wind and clear, how the ancients stargazing fixed the season [surging ask bar podcast 21]

When the annual movement of the sun gave birth to the natural changes of yin and yang and the rise of the four, the ancients looked for the connection between themselves and the vast nature in observing the sunrise and moon setting and the shifting of the stars. And today, in the song of "spring rain shocks the spring valley days, summer is full of mango and summer and summer are connected", we place our imagination on the grass warblers flying or frost and snow in the sky, and also look for the power of time rolling forward and the cycle of life.

After a long history, the twenty-four solar terms are gradually moving out of the categories of agriculture, astronomy and nature, and have become the coordinates of cultural time Chinese. In this issue of the surging question, we invite Fang Yun, ph.D. in folklore from East China Normal University, and Wang Jichen, Ph.D., ph.D., from the perspective of science and aesthetics, to systematically discuss the invention and evolution of the twenty-four solar terms. When the ancients looked at the heavens, would they divide the morning and evening shifts? How does the C major of the rhythm echo the winter solstice? During the Song and Yuan Dynasties, why do you make popcorn during the Rain Festival? The above questions are welcome to look for answers in the program.

【Audio】 Pear blossoms are windy and clear, how the ancients watched the stars and fixed the solar terms

【Music】

Memories of Marigold- Howard Harper-Barnes

插 曲：Every Reason I Know-Bireli Snow

【Timeline】

07:40 Is there really a scientific basis for the spring equinox egg?

12:25 Qingming sacrifice turns strange undead into relatives

24:57 Winter Solstice Nine Nine Cold Relief Chart: The spiritual comfort of the ancient literati who survived the winter

28:40 Rain Festival for popcorn divination harvest

42:00 Aesthetics and creativity in Yuan Ming's "Suiyuan Food Menu"

44:30 Why did the ancients observe the heavens in the morning and evening shifts?

53:05 Correspondence of the winter solstice to C major

59:10 There is no beginning or end of the four seasons, and the ancients advocated the Taoist temple

01:07:05 People predict the weather through technology, but they also lose their awe of eclipses and lunar eclipses

01:14:55 It doesn't matter if the solar terms are accurate

【The following is an excerpt from this interview】

The Paper: Why did the "Qingming" festival develop into a traditional festival "Qingming Festival"? Why did the festival change from walking on the green to worshiping ancestors and visiting the tomb?

Fang Yun: The origin of the Qingming Festival, there is a process from the festival to the festival merger, which merges a cold food festival. The festival of cold food originated from the ancient people's belief and worship of the fire god. In the ancient court, the fire system was very important. According to records, the fire-changing system in the Tang Dynasty period was first from the palace, and then lit one by one after the fire was obtained by drilling wood, and the civil and military officials were arranged well, and one by one the candles were lit and passed on, and everyone welcomed the new fire to their own homes, that is, "the candles were passed on in the Han Palace at dusk, and the light smoke was scattered into the five hou families." Because the ancients believed that fire is a living thing, the same fire cannot be used all year round, and the fire will be extinguished after a long time, and it needs to be re-fired.

After the Song Dynasty, sacrifices began to flourish. Because ancient China had a strong concept of clans, temple sacrifices were generally held in clan ancestral halls, from the royal family to the people, there were such customs, so the customs of "QingmingHui" or "eating Qingming" often appeared everywhere. As long as the family has the same surname and the same origin, they will worship the ancestors at this time, and after the sacrifice is completed, the sacrifice will be divided into food. It is precisely because of the earliest ancestral hall festival that it slowly evolved into a tomb festival. When participating in tomb sacrifices, people often wear willow branches on their heads, which is said to ward off evil spirits and protect their descendants.

The Paper: Why did the ancient literati draw the 99-9 cold map on the winter solstice? Has this custom disappeared now?

Fang Yun: "Nine Nine Cold Removal Chart" is more of an artistic act. There are literati and scholars who love to paint plum blossoms, nine petals on a flower, one petal a day, and when they are painted, it is exactly nine nine eighty-one days. There is also a more advanced way to play is to write words, the total stroke of the word must be nine paintings, the word post is drawn like red, and the long winter has passed.

The ancient literati came up with this design because the eighty-one days after the waxing moon were regarded as the coldest season. In order to survive the long winter, there must be some meaningful way to record it, and the weather will become very warm after the painting.

The Paper: What is the relationship between the twenty-four solar terms and the twenty-four flower trade winds and the seventy-two seasons?

Fang Yun: In fact, the twenty-four flower trade winds are not distributed in the twenty-four solar terms, not one solar term corresponds to one flower trade wind, but refers to the eight solar terms in spring, each of which has three flower trade winds. For example, from xiao han is plum blossom camellia and daffodil, big han is Ruixiang orchid and alum, Li Chun is Yingchun, cherry and wangchun, rain is cauliflower, apricot blossom, plum flower, etc., the names here are not listed one by one, until the valley rain.

On the one hand, because the most beautiful season of spring is closely related to flowers. In nature, flowers are considered to be the role of the messenger, even if anything may be deviated, the flower will always come as promised, and the word "flower letter" will come from this. This also makes flowers the object of many poets' songs. Poets gave personality to each flower, and through literary descriptions, the imagination of flowers was fixed, and twenty-four flower trade winds were formed.

On the other hand, the ancients attached great importance to the reproduction of heirs, and the worship of the flower god was widespread in folk customs, believing that flowers were a symbol of life and fertility. Every year during the spring equinox in February, there is a flower festival for the worship of the flower god for the public. In particular, the worship of the flower god in the south is more intense, because flower farmers need to grow flowers. Since the Beginning of the Song Dynasty, the flower economy has been very prosperous; after the Yuan Dynasty, the cotton industry has developed, and cotton has been slowly promoted into China through sea and land routes, and the people have really put on warm cotton clothes, so there is the concept of "clothes under the world". Therefore, the flower gods sacrificed at the Flower Festival are not only ornamental flowers, but also a type of cotton. Therefore, the significance of the twenty-four flower trade winds is also continuing and extending in the course of history.

The Paper: How were the twenty-four solar terms first established?

Wang Jichen: Solar terms are not invented by a single person, and its production and perfection is a long historical process. We can trace our earliest back to the late Neolithic period. Before 2000 BC, In Xiangfen, Shanxi, legend has it that Emperor Yao built the capital there. After years of archaeological excavations and field observations, archaeologists finally found a prehistoric observatory on the site. After astronomers' calculations and field surveys, the ancients could use the sun to rise between the slits of the stone pillars and the tangents of the ridge to determine the two solar terms of the winter solstice and the summer solstice. This discovery verifies the account in the Shang Shu Yao Dian that Yao formulated the calendar.

During the Spring and Autumn Period, there are already records of "points, solstices, openings, and closures" in ancient books, the so-called divisions, that is, spring and autumn equinoxes and winter and summer solstices, and opening and closing refers to the establishment of spring, winter, autumn, and summer. Divide and close together to become eight knots. In the pre-Qin document "Yi Zhou Shu", there were records of the four spring seasons of rain, sting, valley rain, and Qingming, but the order is not consistent with today. Then in the early Western Han Dynasty's "Huainanzi", the appearance of the twenty-four solar terms was officially seen. But we need to know that before the "Huainan Zi", especially during the Qin Dynasty, many excavated documents have vaguely seen some sporadic records of the twenty-four solar terms, of course, some names and orders are not completely consistent with today, but there should be a clear inheritance relationship before and after.

During the reign of Emperor Wu of the Han Dynasty, the astronomer Luo Hong introduced the twenty-four solar terms into the Taichu Calendar and invented the method of placing leaps without neutral gas, which was implemented in the Chinese official revision calendar for more than a thousand years. The reason why we have the phrase "Spring Festival" today is because of the integration of the solar terms into the official calendar. By the way, the beginning of the past year is arranged on the day of the spring every year, called the Spring Festival, and the beginning of the year is arranged on the first day of the first lunar month of the lunar calendar, called New Year's Day. It is completely different from today's New Year's Day and Spring Festival.

The Paper: How did the ancients determine the solar terms based on observing the celestial phenomena?

Wang Jichen: In ancient China, astronomical observations of fixed solar terms mainly used two methods, one is to use the great Mars, bird stars and other stars to carry out mid-heaven observation: in the important solar terms, the stars that appear in the southern position of midnight are used as symbols. Whenever a particular star comes to the middle heaven, it represents the arrival of a certain solar term.

The other is the immediate shadow measurement method taken during the day. The change in the position of the direct sun point has led to the division of the four seasons of spring, summer, autumn and winter in the northern hemisphere. The sun altitude angle will be higher in summer and lower in winter. This regularity change can be intuitively seen through the length of the shadow. The ancients therefore invented the gui table, the pole perpendicular to the ground is called "table", and the scale scale placed flat on the ground is called "gui". In this way, according to the length of the shadow projected on the ground by the watch rod, the solar terms can be clearly distinguished, the longest time of the shadow in a year is the winter solstice, the shortest time of the shadow is the summer solstice, and then the increase or decrease of the period is divided into twenty-four equal points, that is, the specific solar term corresponding to the shadow length of a certain day is known.

The Paper: With climate change, will the twenty-four solar terms deviate today?

Wang Jichen: Limited by time and space, deviations have always existed. For example, the Song Dynasty and the Ming Dynasty both experienced the Xiaoice River Period, and the global climate was much colder than it is today. But at any time, the twenty-four solar terms always have a very important significance, because it divides the year into twenty-four equal parts, similar to dividing a day into twenty-four hours. It's like what to do every morning at six o'clock and twelve o'clock in the afternoon, providing a time frame. This structural framework is applicable in the northern hemisphere, because as long as the two days of summer solstice and winter solstice are set according to the difference in the altitude angle of the sun, the temperature and heat changes of the year are basically fixed. Based on this set of time frames, we will arrange sunrise and sunset, and we can flexibly fill various behavioral activities in each specific moment, so the twenty-four solar terms have a strong adaptability.