What does a birthday include?

Birthday, referred to as "eight characters", refers to the calendar date when a person was born; Year, month, day, * * * four columns, each column has two words, and * * * eight words.

The eight characters originated in ancient China, which is a method to accurately record the year, month, day and time by using heavenly stems and earthly branches. It consists of eight branches (eight characters * * *), namely, annual stem, annual branch, monthly stem, daily branch, daily stem and hour branch and annual branch.

Extended data:

Conversion method—

To learn eight characters, you should be familiar with a set of methods to change eight characters in time. First of all, every year starts from beginning of spring, and the month from beginning of spring to fright is (similar to the first month of the lunar calendar), which starts with the minute of "Festival" (not noon) and ends with the last minute of "Qi". Then calculate the heavenly stems and earthly branches of the moon column, the sun column and the time column in turn.

Since the astrology only reflects the relative angular position of the earth and the sun, the conversion of the astrological formula of time needs to refer to many factors, including average solar time, sidereal time, average time difference, time zone, daylight saving time, even longitude, and the relative angle between longitude and solar sunshine. This conversion algorithm is more accurate, but it is also complicated, mostly with the help of computer-aided calculation, usually with a perpetual calendar, and the formula is simple.

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