what are the three types of celestial objects in the .....10

Various sources point to the seven day week originating in ancient Babylonia or Sumeria, with possible origins dating back to the Egyptians. It has been suggested that a seven day week might be much older, deriving from early human observation that there are five celestial objects which move in the night sky relative to the fixed stars (plus the Sun and the Moon). In any event, a seven day week based on heavenly luminaries eventually diffused both East and West, to the Romans via the Greeks, and to the Japanese via Manicheans, Indians and Chinese.



The earliest known reference in Chinese writings is attributed to Fan Ning, who lived in the late 4th century, while diffusions via India are documented with the writings of the Chinese Buddhist monk Yi Jing and the Ceylonese or Central Asian Buddhist monk Bu Kong of the 8th century. The Chinese transliteration of the planetary system was soon brought to Japan by the Japanese monk Kobo Daishi; surviving diaries of the Japanese statesman Fujiwara Michinaga show the seven day system in use in Heian Period Japan as early as 1007. In Japan, the seven day system was kept in use (for astrological purposes) until its promotion to a full-fledged (Western-style) calendrical basis during the Meiji era.





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