How often do the sun and the moon shine together on average? What does it symbolize?

How often do the sun and the moon shine together on average? Almost twice a month (lunar calendar), once in the afternoon of the first half of the year and once in the morning of the second half. The principle of the sun and the moon shining together is only a natural phenomenon, and the phenomenon of the sun and the moon shining together requires the sun and the moon to be above the horizon at the same time. Theoretically, as long as the atmospheric conditions are good, this phenomenon may occur except the fifteenth day of the lunar calendar. But there is a second condition, that is, the limit magnitude of the sky (the darkest celestial body that can be seen) cannot be too low, so generally speaking, when the sun rises or is about to set, the brightness of the sky can easily meet this condition (even in cities). Therefore, in the first half of the lunar calendar (after the fourth day of the lunar calendar), you can see the moon phase when the sun goes down, from west to east in turn, and from west to east in turn after the sun rises in the second half of the lunar calendar (before the twenty-seventh day). What do the sun and the moon symbolize? In some stories, it represents the emergence of evenly matched people or forces. But in fact, in the realistic environment of ancient times, it is a good omen that the sun and the moon shine together. Duke Zhou said that both the sun and the moon are bright, which indicates good luck. In ancient times, some people made this into an inkstone, which means that the future is bright and the promotion is step by step. If we insist on careful observation and thinking, we can also find that the moon and the sun can actually appear in the sky at the same time every day, but the time when the sun and the moon shine together will be long and short, some days only last for a few minutes, but some days can last for several hours, and the two time periods that are easy to be observed are just the latter, so it is easier to be seen. On different days, the duration of the sun and the moon shining together should be calculated by the movement law of the moon and the sun in the sky. The sun and the moon shine together. It must be that the closer the moon is to the sun, the longer it lasts (equivalent to rising and falling together), just because when the moon is too close to the sun, it will be submerged in dazzling sunlight and cannot be observed. Several parameters used in the calculation are as follows: a = 29.5/360 = 0.0819/1-The age of the moon corresponding to the unit distance angle between the moon and the sun ω= 360/24h = 15/h- the running speed of the moon and the sun in the sky (ignoring the revolution of the earth, In this way, we can draw the following conclusions: φ= x/a- the distance angle between the moon and the sun. Through the above equation, we can calculate the duration of the sun and the moon's brilliance, which can last for five or six hours in the days around the eighth day (that is, the winding), that is, we can see this phenomenon five or six hours before the sun sets in the west.