Who is the culprit of the perpetual calendar?

Weather phenomena or astronomical phenomena. The "prank" in the perpetual calendar refers to a weather phenomenon or astronomical phenomenon, which means that due to the inclination of the earth's rotation axis, different sun positions appear in different parts of the earth at different times, thus causing changes in the length of day and night, the height of the sun, the time of sunrise and sunset, etc. This kind of change will be different in different regions and seasons, which is also called "prank". In the calendar, "pranks" are used to describe and predict these changes, so that people can better arrange production and daily life. "Noisy" is not a specific person or thing, but a natural phenomenon.