199 1 what is the lunar calendar?

199 1 agricultural calendar is as follows:

Lunar calendar is one of the traditional calendars in China, also known as lunar calendar, ancient calendar, Han calendar, yellow calendar, summer calendar and old calendar.

In astronomy, it mainly refers to the calendar arranged according to the moon phase cycle, in which the moon orbits the earth once (based on the sun, the actual moon orbits more than once). ) is January, which is a calendar based on the moon. There are twelve calendar months in a year. In the process of calendar development and evolution, the emergence of 24 solar terms was used to guide agricultural production scientifically, and the lunar calendar (Han calendar) was formed.

Only when the moon revolves around the earth, the position of the earth changes, counting forward more than 27 degrees. The moon runs at the speed of 13 degrees 15 minutes every day, so it takes 29 days 12: 44: 2.8 to return to the moon. This is called "the first moon", which is called a month by custom, meaning