Zu Chongzhi

Zu Chongzhi

Zu Chongzhi (429-500) was an outstanding mathematician and astronomer during the Northern and Southern dynasties (420-589). He devoted his life to the study of natural sciences and made remarkable contributions to mathematics, astronomy, calendrical calculations, and mechanical engineering.

Zu was the first to calculate the value of pi to an accuracy of seven decimal places, between 3.1415926 and 3.1415927, which was a major contribution to China and the world. His calculation of Pi was later named after him as "Zu Chongzhi's Pi", and this record in accuracy was not surpassed until the 16th century. In addition, the "Daming calendar" Zu compiled was the most accurate calendar at that time. His calculation of the length of a tropical year differs from the modern value by only 46 seconds; it laid solid foundations for astronomical research worldwide.

To celebrate Zu Chongzhi's remarkable contributions to science and culture, the Purple Mountain Observatory named an asteroid – which was discovered in 1964 and given the international permanent number 1888 – "Zu Chongzhi Star".

祖沖之

祖沖之（429—500）是南北朝時期杰出的數學家、天文學家。他一生鉆研自然科學，在數學、天文歷法和機械制造等方面都作出了卓越的貢獻。

祖沖之首次將圓周率精算到小數點后第七位，即在3.1415926和3.1415927之間。他對圓周率數值的精確推算值，對于中國乃至世界是一個重大貢獻，后人將“這個精確推算值”用他的名字命名為“祖沖之圓周率”。直到16世紀，這一精算紀錄才被打破。此外，由祖沖之撰寫的《大明歷》是當時最科學、先進的歷法。按照他的推算，一個回歸年的長度和今時的推算值僅相差46秒，這為世界天文研究奠定了堅實基礎。

為了紀念祖沖之對中國和世界科學文化作出的杰出貢獻，紫金山天文臺將1964年發現的國際永久編號為1888的小行星命名為“祖沖之星”。