The chinese language calendar
proof from the Shang oracle bone inscriptions suggests that at least by the 14th century BCE the Shang dynasty chinese language had installed the solar year at 365 1/four days and lunation at 29 half of days. in the calendar that the Shang used, the seasons of the 12 months and the stages of the Moon have been all supposedly accounted for.
one of the methods that they used to make this calendar changed into to add an additional month of 29 or 30 days, which they termed the thirteenth month, to the end of a ordinary 12-month year. there’s also proof that suggests that the chinese advanced the Metonic cycle (see above complex cycles)—i.e., 19 years with a total of 235 months—a century in advance of Meton’s first calculation (no later than the Spring and Autumn period, 770–476 BCE).
in the course of this cycle of 19 years there had been seven intercalations of months. the other technique, which changed into abandoned quickly after the Shang began to undertake it, became to insert an additional month between any months of a regular 12 months. likely, a lack of astronomical and arithmetical information allowed them to do this.
chinese calendar from the 18th century.pictures.com/Jupiterimages by means of the 3rd century BCE the first technique of intercalation became regularly falling into disfavour, while the status quo of the meteorological cycle, the ershisi jieqi, during this period officially revised the second one technique. This meteorological cycle contained 24 points, each beginning one of the durations named consecutively the Spring starts, the Rain Water, the Excited insects, the Vernal Equinox, the clear and vivid, the Grain Rains, the summer season starts offevolved. 
the Grain Fills, the Grain in Ear, the summer season Solstice, the mild warmness, the high-quality warmness, the autumn begins, the limit of warmth, the White Dew, the autumn Equinox, the bloodless Dew, the Hoar Frost Descends, the wintry weather starts, the Little Snow, the Heavy Snow, the iciness Solstice, the Little bloodless, and the extreme cold. The established order of this cycle required a truthful quantity of astronomical know-how of the Earth as a celestial frame, and with out problematic gadget it is not possible to gather the necessary information. 
modern scholars well known the superiority of pre-Sung chinese language astronomy (at the least till about the thirteenth century CE) over that of different, cutting-edge nations.
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