Sima Qian was born at Xiayang in Zuopingyi (around present-day Hancheng, Shaanxi Province). He was most likely born about 145, though some sources give his birth year as about 135. Around 136, his father, Sima Tan, received an appointment to the relatively low-ranking position of "grand historian" ("tàishǐ" , alt. "grand scribe" or "grand astrologer"). The grand historian's primary duty was to formulate the yearly calendar, identifying which days were ritually auspicious or inauspicious, and present it to the emperor prior to New Year's Day. Besides these duties, the grand historian was also to travel with the emperor for important rituals and to record the daily events both at the court and within the country. By his account, by the age of ten Sima was able to "read the old writings" and was considered to be a promising scholar. Sima grew up in a Confucian environment, and Sima always regarded his historical work as an act of Confucian filial piety to his father.