Modern calculations test an ancient Chinese record

Historical Chinese records describe the Sun rising twice at Zheng. The date is reconstructed as 21 April 899 BCE; the negative year follows this database's BCE convention.

The observation shows how court astronomy combined counting, calendrical cycles and systematic recording long before modern mathematical astronomy.

Accurate calendars mattered for ritual and government, showing that mathematical knowledge developed inside social institutions rather than through isolated individuals.

The Bur-Sagale eclipse was recorded in the Assyrian eponym lists. Its date, 15 June 763 BCE, anchors Near Eastern chronology.

Modern astronomical calculation connects the ancient record to an exact day, helping date rulers and events across Assyrian history.

Long sequences of observations enabled scholars to identify regularities in celestial events and refine numerical schemes.

The record shows that numerical astronomy and chronological calculation flourished in Mesopotamia centuries before classical Greek science.