What is the constellation based on?

Gregorian calendar is the universal Gregorian calendar. 1949 On September 27th, the first plenary session of China People's Political Consultative Conference adopted the internationally accepted Gregorian calendar era, and designated Gregorian calendar 1 month 1 day as New Year's Day and New Year's Day. Because the first day of the first lunar month is usually around beginning of spring, the first day of the first lunar month is designated as the "Spring Festival".

The origin of Gregorian calendar (Gregorian calendar)

At the end of Rome and the Republic, Caesar formulated the julian calendar according to this calendar of ancient Egypt, which was implemented throughout Rome. Julian calendar has a big moon of 3 1 day and a small moon of 30 days, alternating between big and small months. Every four years is a leap year, with 30 days in February and 29 days in a normal year.

When Caesar's nephew Octavian ruled Rome, because Octavian's birthday was in August, he changed August to a big month, September to a small month, and so on, subtracting one day from mid-February.

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