Guo Shoujing

Bust of Guo Shoujing

Guo Shoujing (Chinese: 郭守敬; Pinyin: Guō Shǒujìng; Wade-Giles: Kuo Shou-ching) (* 1231 in Xingtai ; † 1316 ) was a Chinese hydraulic engineer , astronomer and mathematician .

Life

He was raised after his father's untimely death by grandfather Guo Yong, a scholar educated in subjects such as the Confucian classics, mathematics, and hydraulics. The child quickly developed an unusual talent. When the official and scholar Liu Bingzhong (1216–1274) came to Xingtai in 1246 and gathered a number of great intellectuals (including Zhang Wenqian) around him, Guo Yong took the opportunity and had his grandson study with Liu Bingzhong (approx. 1246–49 ). At the age of 20, Guo Shoujing planned the successful reconstruction of a (washed away) stone bridge over the Dahuoquan, thereby demonstrating his talent to local officials (1251).

In June 1260, following Zhang Wenqian's entourage, he was given the opportunity to learn about the irrigation systems of various districts. At the same time, he constructed and improved some astronomical instruments, whereupon the impressed Zhang Wenqian arranged an audience with the ruler Kubilai Khan . He submitted six specific suggestions to improve the water management in northern China and immediately received a post in the water administration, in which he then gradually rose. In 1271, as "director", he was given supervision over hydraulic engineering, the complex problem of river regulation and irrigation in China.

Among other projects, he built the northernmost section of the Imperial Canal , the Tonghui Canal (80 km long), which served to supply the capital Beijing (then: Dadu or Khan-balyq) with grain from the south. At that time the Kaiserkanal had to be re-routed and extended to the capital. The old route was too long for the new requirements and no longer sufficiently navigable. Another project was the Kunming Lake , which served to supply the capital with water.

His second field of activity was astronomy, together with his colleague Wang Xun (Wang Hsun). The Khan had invited the Persian astronomer and geographer Jamal ad-Din († around 1301) to China. He came in 1267, brought astronomical devices and a new, better calendar with him, the "Wan nien li" calendar. As a result, the Khan established an Institute of Muslim Astronomy to attract Persian and Arab astronomers, and gave scientists a higher status in society. In 1276, Guo Shoujing was commissioned to reform the calendar. To obtain better data on the course of the sun (today we would say Earth orbit) he built the Gaocheng Observatory . Based on the Persian knowledge he developed a new calendar by 1280, the Shou shih li (授 時 曆), which, with small changes, was 364 years, i.e. H. was still used through the Ming period. The year length in this calendar of 365.2425 days corresponded to the Gregorian calendar from the end of the 16th century. Guo Shoujing also constructed astronomical instruments that were assembled by a Nepalese named Arniko and used for 500 years.

Besides Zhu Shijie , the author of two mathematical works (1299/1303), he is also one of the great mathematicians of his time.

The International Astronomical Union honored him with the naming of the asteroid (2012) Guo Shou-Jing .

literature

• Igor de Rachewiltz, Hok-lam Chan, Hsiao Ch'i-ch'ing, Peter W. Geier a. a .: In the Service of the Khan - Personalities of the Early Mongol-Yüan Period , Wiesbaden 1993

Web links

• John J. O'Connor, Edmund F. Robertson :  Guo Shoujing. In: MacTutor History of Mathematics archive .
• Article on the Shoushi calendar from the National University of Singapore (PDF file; 509 kB)

Note: This article places the family name before the person's first name. This is the usual order in Chinese. Guo is the family name here, Shoujing is the first name.