(429 – 500 AD)
Ancient science comprised mostly of raw maths. And while Europe dozed-away in the Dark Ages, Asia produced formidable mathematicians. Among the most notable of all is Zu Chongzhi (whose name is sometimes written as Tsu Chungchi). As a child, Zu displayed remarkable intellect, and was referred to the esteemed Hualin Xuesheng Academy before proceeding to the prestigious Imperial Nanjing University. He excelled in his studies: with predilection for maths. This mathematical flair augured well with his future research in astronomy. It enabled him to calculate the values of time with unprecedented accuracy. For example, his calculation of one year as 365.2428148 days is very close to our contemporary value of 365.2421988 days. The same is true for his number of overlaps between sun and moon: 27.21223, which is very similar to the 27.21222 we use today. With that overlaps-value, he accurately predicted eclipses. Again, his computation of Jupiter’s year as 11.8580 earth years fell short by only 0.004 earth year. Apart from advancing Liu Hui’s works, Zu Chongzhi was able to resolve the volume of a sphere, and calculated pi so accurately that his approximation became the standard for almost a millennium. He also dabbled into mechanical engineering, re-invented Ma Jun’s south-pointing chariot, and in collaboration with his son (named Zu Gengzhi), authored his famous (but long lost) math treatise titled Zhui Shu. Befittingly, Zu Chongzhi’s name is immortalized in several mathematical concepts which range from pi-ratio to encryption-algorithm. He is also the eponym of the 1888 Zhu Chong-Zhi asteroid, and the Tsu Chung-Chi lunar crater.