Group 1 - The lunar calendar is a traditional Chinese calendar that balances the lunar cycle and the solar year, consisting of 12 months, with each month being either 29 or 30 days long [2] - A year with only 12 lunar months averages 354 days, which is about 11 days shorter than the solar year, leading to seasonal misalignment [2] - To correct this, the ancient Chinese devised the method of adding a leap month every two to three years, known as a leap month [2] Group 2 - The reason for the occurrence of a leap month in June is tied to the 24 solar terms, which are crucial for determining leap months [4][6] - Each lunar month must contain a solar term; if a month lacks a solar term, it is designated as a leap month from the previous month [6] - In the current lunar calendar, the month following June contains only one solar term, which is the beginning of autumn, thus making June a leap month [6] Group 3 - There are six instances of leap June in this century, occurring in the years 2017, 2025, 2036, 2055, 2074, and 2093 [11][12]

Core Viewpoint - The article discusses the traditional Chinese lunar calendar, its structure, and the phenomenon of leap months, emphasizing that leap months are a normal occurrence in the calendar system and not related to climate anomalies [1][10]. Group 1: Lunar Calendar Structure - The lunar calendar is based on the moon's orbit around the Earth and the Earth's orbit around the sun, making it a lunisolar calendar [1]. - A lunar month is determined by the lunar cycle, averaging 29.53 days, leading to a lunar year of approximately 354 or 355 days, which is about 11 days shorter than a solar year [5]. - To align the lunar calendar with the seasons, ancient astronomers implemented a leap month system, adding 7 leap months in a 19-year cycle [6]. Group 2: Leap Month Mechanism - The leap month is determined based on the presence of solar terms, which divide the Earth's orbit into 24 segments, ensuring that each lunar month contains a solar term [6]. - If a lunar month lacks a solar term, it is designated as a leap month, with the current example being "leap June" in 2023, which has 29 days [7]. Group 3: Historical Context and Climate Relation - Leap June occurrences are not rare, with six instances recorded in the current century, including years like 2017 and 2025 [10]. - Recent extreme heat has been mistakenly linked to the leap month phenomenon, but experts clarify that leap months are a standard calendrical occurrence and do not indicate climate anomalies [10].

Core Viewpoint - The article discusses the occurrence of a leap month in the lunar calendar, specifically the leap June in 2023, and explains the astronomical reasoning behind it [2][6]. Summary by Sections Lunar Calendar Explanation - The lunar calendar is based on the moon's orbit around the Earth and the Earth's orbit around the sun, making it a lunisolar calendar [2][6]. - A lunar month is approximately 29.53 days, leading to a lunar year of about 354 or 355 days, which is about 11 days shorter than a solar year of 365.24 days [6]. Leap Month Mechanism - To align the lunar calendar with the solar calendar, ancient astronomers introduced leap months, adding 7 leap months in a 19-year cycle [6]. - The placement of leap months is determined by the 24 solar terms, which divide the Earth's orbit into 24 segments [6]. Current Leap Month Details - In 2023, the leap month is designated as "leap June," occurring from July 25 to August 22, with only one solar term (Liqiu) present in this period [6]. - The leap month has 29 days, and the absence of a solar term in the preceding month led to its designation as a leap month [6]. Frequency of Leap Months - This century will see a total of six occurrences of leap June, specifically in the years 2017, 2025, 2036, 2055, 2074, and 2093 [7]. Climate Connection - The article clarifies that the recent extreme heat is not related to the leap month phenomenon, emphasizing that leap months are normal occurrences in the lunar calendar [8].

Core Points - The arrival of the "Small Heat" solar term indicates that the "Three伏" (Three Folds) period is approaching, which is characterized by high humidity and heat [2][3] - Traditional customs during this period include eating dumplings and "伏羊" (eating lamb), which are believed to help replenish energy and improve appetite [3][5] - The practice of "食新" (eating new food) during Small Heat signifies the harvest of new grains and encourages people to maintain energy balance by consuming fresh produce [5] Summary by Category Seasonal Significance - "Small Heat" serves as a reminder that the hottest days of summer, known as "Three Folds," are near, prompting preparations for the upcoming heat [2] - The overlap of "Small Heat" and "Three Folds" indicates that the weather will become increasingly hot and humid [2] Traditional Customs - Eating dumplings is a common practice during this period, particularly on the first day of "Three Folds," as it is believed to aid digestion and replenish energy [3] - The custom of eating lamb during "伏天" is rooted in the belief that it provides warmth and nourishment during the hot and humid weather [3] Agricultural Practices - The "食新" custom involves consuming newly harvested grains and vegetables, which reflects the agricultural cycle and the importance of fresh produce in maintaining health during the summer [5] - The saying "小暑黄鳝赛人参" highlights the nutritional value of eel during this time, suggesting it is particularly beneficial for health [5]

Core Insights - The article discusses the significance of the summer solstice in ancient Chinese civilization, highlighting its historical and astronomical importance as one of the earliest recorded solar events in China [1][3][12] Group 1: Historical Significance - The Taosi site is recognized as a key archaeological site for understanding the origins of Chinese civilization, alongside other significant sites like Liangzhu and Erlitou [1] - The ancient people of Taosi developed a solar calendar, marking the summer solstice as a crucial agricultural time marker [3][6] Group 2: Astronomical Observations - The Taosi astronomical observatory, with a radius of 10.5 meters and 12 observation slits, allowed ancient inhabitants to accurately track celestial movements and define 20 solar terms, which are foundational to the traditional 24 solar terms [3] - The use of a gnomon and a horizontal measuring stick (known as a "gui") complemented the observatory, enabling precise measurements of shadow lengths to establish a solar calendar [6] Group 3: Cultural Practices - The article describes how ancient people observed natural phenomena, such as the shedding of deer antlers and the emergence of cicadas, to mark seasonal changes and agricultural practices [8][10][12] - The concept of "half summer" is introduced, referring to a medicinal plant that grows during this period, symbolizing the transition of seasons and the balance of yin and yang [12]

Group 1 - The summer solstice is the tenth solar term and the fourth term of summer, occurring on June 21, 2025, marking the halfway point of summer [2] - The term "solstice" indicates the maximum solar radiation received at the northernmost point of the Earth, particularly affecting areas north of the Tropic of Cancer [2] - The tradition of eating noodles during the summer solstice is linked to the harvest of wheat in northern regions and the belief that hot noodles can expel dampness from the body [2] Group 2 - The "Three伏天" (Three Fu Days) is a traditional Chinese concept indicating the hottest and most humid period of the year, typically occurring from mid-July to late August [2] - The calculation of the Three Fu Days is based on a dual coordinate system involving the "Geng Day" and solar terms, reflecting ancient wisdom in observing nature [3] - The initial Fu period starts on the third "Geng Day" after the summer solstice and lasts for 10 days, while the middle Fu period varies between 10 to 20 days depending on the number of "Geng Days" between the summer solstice and the beginning of autumn [3][4] Group 3 - In 2025, the initial Fu period will last from July 20 to July 29, the middle Fu period from July 30 to August 8, and the final Fu period from August 9 to August 18, totaling 30 days, categorized as a "short Three Fu" [4] - The calculation system for the Three Fu Days showcases the integration of astronomical observations, climate patterns, and practical life applications, which remains relevant in modern agricultural practices and urban emergency planning [4]

Group 1 - The core concept of the article revolves around the significance of the "Xiaoman" solar term in the context of ancient Chinese astronomy and its philosophical implications, highlighting the integration of natural observations and life wisdom in Chinese civilization [1][5][8] - The "Xiaoman" solar term is defined as occurring when the sun reaches a longitude of 60 degrees, marking a specific point in the solar calendar [3][10] - Historical records indicate that the complete system of the 24 solar terms was developed by the Warring States period, linking each term to various astronomical phenomena and agricultural practices, thus embodying the "unity of heaven and humanity" philosophy [5][8] Group 2 - The article discusses the evolution of the 24 solar terms from ancient texts, particularly the "Huainanzi," which first documented the complete system, emphasizing the meticulous astronomical observations made by ancient Chinese astronomers [3][10] - It highlights the discrepancy between the ancient and modern observations of the sun's position during the "Xiaoman" term, attributing this to the phenomenon of precession, which alters the relative positions of celestial bodies over time [10] - The article illustrates how the ancient Chinese astronomers' observations were not incorrect but rather reflect the changes in the celestial background due to the precession of the equinoxes, demonstrating the depth of their astronomical knowledge [10]

Core Insights - The China Pavilion at the Osaka Expo has received over 200,000 visitors in its first month, averaging about 7,000 visitors per day, making it one of the most popular pavilions at the expo [1][2] Group 1: Pavilion Highlights - The theme of the China Pavilion is "Building a Community of Life Between Man and Nature - The Future Society of Green Development," featuring multiple unique exhibition areas [1] - The pavilion's design resembles a scroll of Chinese literature, showcasing both ancient civilization and modern technology [1] - A significant exhibit is a large circular screen displaying multimedia images themed around the "Twenty-Four Solar Terms," illustrating the harmony between humans and nature [1][2] Group 2: Visitor Experience - The pavilion has implemented a humanized flow mechanism to prioritize the entry of special groups, including the elderly, children, and disabled individuals, supported by around 60 volunteers [2][3] - Visitors have expressed admiration for the cultural connections between China and Japan, noting similarities in seasonal changes and traditional aesthetics [2] - The pavilion features a replica of the 4-meter tall bronze tree from the Sanxingdui site, which has impressed many visitors and reshaped their understanding of Chinese bronze artifacts [2][3] Group 3: Cultural Significance - The pavilion aims to convey the warmth of Chinese culture and its respect for vulnerable groups, as highlighted by the experiences of international visitors [3] - The "Moon Soil" exhibit, showcasing samples from China's Chang'e missions, has drawn significant interest, with visitors expressing amazement at China's achievements in space exploration [3] - An AI-generated mural titled "Co-creating Peach Blossom Land" allows visitors to contribute to a collective artwork, emphasizing the theme of global cooperation [3][4]

Core Points - The article discusses the significance of the "Xiaoman" solar term, which is the eighth of the twenty-four solar terms, marking the second solar term of summer, starting on May 21, 2025 [2][3] - "Xiaoman" symbolizes the maturation of crops, with different regions having their own specific crops that signify this period, such as barley and oilseed rape in the Jiangnan region, and wheat and peas in the northern regions [2][3] - The term "Xiaoman" reflects a balance of fullness without overflow, indicating the growth stage of crops and the relationship with rainfall [3][4] Summary by Sections - **Crops and Maturation**: In regions like Beijing, Liaoning, and Shandong, cherries are maturing, while lychees are being harvested in Fujian and Guangdong. The term "Xiaoman" is associated with the growth of winter wheat and other summer crops, which begin to fill out but are not yet fully mature [3][4] - **Cultural Significance**: The article highlights the philosophical implications of "Xiaoman," suggesting that it embodies the wisdom of ancient agricultural practices and reflects a cultural understanding of balance, as seen in the transition to the next solar term "Mangzhong" [4][5] - **Philosophical Insights**: The concept of "Xiaoman" is linked to traditional Chinese philosophy, emphasizing moderation and the idea that excess can lead to loss, as illustrated by the saying "water full will overflow" [4][5]

Group 1 - The Qingming Festival marks the transition between mid-spring and late spring, embodying the cultural tradition of honoring ancestors and reflecting on the past [6][9] - During the Qingming season, the weather is clear and pleasant, making it an ideal time for outdoor activities such as flower viewing and spring farming [7] - There is a long-standing tradition of tree planting during Qingming, as the soil moisture and temperature are suitable for the survival of saplings [11] Group 2 - Eating Qingming rice dumplings, a local custom in the Jiangnan region, involves mixing mugwort, wheatgrass juice, and glutinous rice flour, resulting in a fragrant and not overly sweet treat [13]