Chinanews client, Beijing, August 4th (Reporter Shangguanyun) From the evening of the 3rd to the 4th, the "round moon" maxed out the circle of friends. Many people rushed to publish their photos of the moon and set off a fancy "moon shooting" contest.

　　It’s no surprise that I like to take beautiful pictures of the moon. However, this time the moon is a little special: According to calculations, on June 14 of the lunar calendar this year, the roundest moment of the moon happened to occur at the "last moment" of the day, at 23:59 on August 3.

Data map: On August 3, the moon rose in Beijing Beihai Park. It is reported that in the lunar June of the Year of the Gengzi Rat in 2020, the 15th moon "14 rounds", the fullest time appears at 23:59 on August 3rd. According to astronomy experts, the phenomenon of "14 rounds of the moon at fifteen" is relatively rare, and will only occur 6 times in the 21st century. Photo by China News Agency reporter Du Yang

　　"Fifteen moons and fourteen rounds", why is this?

"The fourteenth moon patted you"

　　"The moon is fifteen and sixteen round." This has almost become a familiar saying. However, on the fourteenth of the lunar month of this year, there is a "fifteenth moon and fourteen rounds".

　　The meaning of this sentence is probably that on the fourteenth of the lunar calendar in the year of the Gengzi Rat, the fullest moment of the moon happened to occur at the last moment of the day, at 23:59 on August 3.

　　Some netizens successively posted photos taken that night, and the bright moon in the night sky looked very beautiful and looked very "cured". Many people made a wish, "Those who wish to see this moon will have good luck next."

　　Some people regret that because of the weather, they have not been able to appreciate this rare full moon. The next time they will have to wait until June 27, 2037, 17 years later, which is the 14th May of the lunar calendar.

　　In fact, the reason why the full moon has attracted attention this time has something to do with its rarity. According to many media reports, this celestial phenomenon will only appear six times in the 100 years of the 21st century.

Why is the fifteenth moon fourteen round

　　The traditional Chinese calendar is the lunar calendar, which takes into account the revolution of the earth around the sun and the revolution of the moon around the earth. Traditionally, people also call the traditional calendar the "lunar calendar."

Data map: On March 9, the 16th night of the year of the rat in the lunar calendar, in Beijing, before the arrival of the "super moon", a full moon rose to reflect the community street lights. Photo by China News Agency reporter Sun Zifa

　　"If you take the sun as a reference, the moon revolves around the earth in 29.531 days. This is what we usually call a synodic moon, which is the cycle of the moon's cloudy, sunny, round and missing." Zhu Jin, honorary curator of the Beijing Planetarium, accepted Chinanews.com The reporter said in an interview.

　　When viewed from the earth, when the projections of the sun and the moon on the ecliptic coincide, it is "Shuo", which is the first day of the lunar calendar; when the projections of the sun and the moon on the ecliptic are exactly 180 degrees apart, it is the lunar calendar. Hope" is the full moon we often say.

　　But because the moon's orbit around the earth is not a perfect circle, but a somewhat flat ellipse, and the orbital surface does not coincide with the orbital surface of the earth's rotation, and the motion of the moon is also affected by the sun and other celestial bodies, so the moon The motion around the earth is not completely uniform, it seems to be fast and slow.

　　Zhu Jin explained that this causes the full moon (wang) of each month to not necessarily be exactly on the fifteenth of the lunar calendar, but may be on any day from the fourteenth to the seventeenth of the lunar calendar.

Check-in scenes: the moon and these related celestial phenomena

　　In addition to the "full moon", there are actually many well-known celestial phenomena related to the moon.

Data map: Previously, the "Super Moon" debuted in Beijing. The picture shows the Zhengyangmen Arrow Tower and the "Super Moon". Photo by China News Agency reporter Mao Jianjun

　　Zhu Jinxian gave an example. For example, solar and lunar eclipses are caused by changes in the relative positions of the moon, the earth, and the sun, including total solar eclipses, ring eclipses, partial solar eclipses, total lunar eclipses, and partial lunar eclipses.

　　He further explained that the solar eclipse must have occurred on the first day of the lunar calendar (New Year). The lunar eclipse must occur at the full moon (wang), so it may occur from the fourteenth to the seventeenth of the lunar calendar. Among them, the total solar eclipse is the most shocking celestial phenomenon that an observer on the earth can personally experience.

　　"In addition, because the moon revolves around the earth every month, planetary conjunctions occur almost every month. There are even rare astronomical phenomena where the moon occludes the planets." Zhu Jin said.

　　In addition, in recent years, the so-called "super moon" has also become very popular. But Zhu Jin believes that it is not a concept of astronomy in the strict sense, but is derived from "astrology." From an astronomical point of view, it itself is not a more meaningful astronomical phenomenon than the full moon.

　　In addition, astronomical phenomena such as "double stars with the moon" and "moon occultation of the Pleiades" also often arouse the enthusiasm of astronomers for observation.

Knock on the blackboard! Here comes the knowledge about the moon

　　Since ancient times, people have never stopped exploring the moon. There are some knowledge points to add about the beautiful moon.

On September 24, 2018, Beijing, a bright moon was in the sky, and the moon was round on the night of Mid-Autumn Festival. Photo by China News Agency reporter Zhai Lu

　　There have been several different theories about the origin of the moon. The various hypotheses about the origin of the moon since the 18th century can be roughly summarized into three categories, namely the homology theory, the split theory and the capture theory.

　　In this regard, Zhu Jin mentioned that the moon is a celestial body that orbits the earth under the gravity of the earth. Therefore, the moon is a satellite of the earth, not an asteroid. "We now know that the moon is not an asteroid that was captured by the earth before."

　　"As for the origin of the moon, the current generally accepted view is that it came from the collision of a Mars-sized planet with the earth in the early stages of the formation of the solar system, and part of that planet and part of the earth eventually formed the moon." Zhu Jin said.

　　In fact, the existence of the moon may have played a very important role in the origin and evolution of life on earth, whether it is through the influence on the stability of the earth's orbit or the influence on the ocean tides on the earth.

　　"However, the gravitational effect of the moon does not have any direct impact on the human body." Zhu Jin said. (Finish)