CCTV News: Qingming is both a solar term and a festival. It carries the deep feelings of the Chinese nation to pursue the distance, and contains ancient wisdom to adapt to the time and get close to nature. So how is Qingming determined? "When the handle of the Big Dipper quietly turned to the southeast, the willow branches in the middle of the Yellow River pulled out their green teeth." This is the record of the astronomer Luo Xiahong on the observatory in the Western Han Dynasty in more than 100 BC. This moment not only means the arrival of the fifteenth day after the vernal equinox, but also marks the solar term "Qingming" that carries the cycle of life, and has once again engraved a mark on the time axis of the Chinese.

"Huainanzi·Astronomy" records: "Fifteen days after the vernal equinox, the Dou point to Yi, and the Qingming wind will arrive." This sentence is a phased summary of the star-gazing and teaching time of the ancestors of China for thousands of years. As early as more than three thousand years ago, the ancestors of China had established the four major solar terms "two to two parts" in Dengfeng, Henan, using the earth and gui, which became the cornerstone of the twenty-four solar terms in later generations. By the Tang Dynasty, monks and their party measured "the day of the Qingming Festival is at the Six Degrees of Lou" through national astronomical measurements, and accurately measured the position of the sun to the specific degree of the constellation. These raw and cold numbers are eternal records of the dialogue between ancestors and stars.

From solar terms to festivals, the trajectory code of the Great Mars

From solar terms to festivals, the trajectory code of the Great Mars

According to popular science experts at the Beijing Planetarium, the ancient fire ban and fire reform systems correspond to the two time nodes of Cold Food and Qingming Festival, and the source can be traced back to the observations of Great Mars by ancestors in ancient times. It turns out that behind the origin of Qingming Festival and some customs, there are more ancient astronomical observation codes hidden.

In ancient times, when our ancestors observed the sun's visual trajectory, they often used stars near the eclipse that rose and set the same as the sun as the standard stars, and observed in the morning and evening. Among them, there is a star closely related to the origin of the solar term - Great Mars.

According to ancient astronomical classics, Great Mars has a special visual orbit. Spring appears on the eastern horizon, summer moves up to the southern sky, autumn slides down to the western sky and quickly disappears below the horizon. The ancient ancestors therefore determined the three seasons of spring, summer and autumn, and used them to guide when to set fire and when to burn the wasteland, and when to harvest and prohibit fire from autumn. This also became the source of the custom of banning fire in the cold food and ignition in the Qingming Festival.

This "Mars" is not the other "Mars".

The popular science experts at the Beijing Planetarium particularly emphasized that the important standard star "Great Mars" in ancient astronomy in my country is not the same as Mars among the eight planets in the solar system that are familiar to the public. It cannot be confused.

Associate researcher of Beijing Planetarium, Yang Fan introduced that the "Big Mars" in ancient China was actually Xinsu II, which is the eastern Canglongjiao, Kang, Di, Fang, Xinsu II is a very bright star. It is also the Alpha Scorpio, which is different from the Mars and planets we are talking about now.

The Great Mars in ancient Chinese astronomical world is also called Shangxing or Chenxing. It is a first-class brightness star emitting fiery red light. In ancient classics during the Warring States Period, there were records of the myths and legends of Suiren and the Great Mars, "Suiren observes the stars above and the five trees below, and thinks it is fire." This is what Suiren looked up at the celestial phenomena, saw that Mars appeared on the horizon in the east at dusk, and looked down at the growth of trees, telling the people that it was time to set fire to the fire. Whether the name "Big Mars" came about is another mystery that remains to be solved by the ancients.