Fifteen moons and sixteen circles are an astronomical phenomenon. The reason is that the lunar standard is that the first day of the lunar calendar must fall on the moon.
Under normal circumstances, in the early morning of the first day, it should be fifteen nights. So the new moon appeared late on the first day, and Wang appeared on the sixteenth. Sometimes even as high as seventeen. The most perfect and brightest moment of the moon is when looking.
What is "hope"? On the first day of the lunar calendar, the moon runs between the earth and the sun, and the illuminated hemisphere of the moon faces away from the earth, so we can't see the moon, which is called "new moon" or "new moon". On the fifteenth and sixteenth day of the lunar calendar, the bright side of the moon faces the earth, so we see a round moon, which is called "full moon" or "full moon".