What calendar did Guo Shoujing revise?

Guo Shoujing presided over the revision of the chronograph calendar, which became the most advanced calendar in the world at that time. Guo Shoujing improved simple instruments and standard watches, and presided over nationwide astronomical surveys.

Guo Shoujing's major achievements are making a chronograph calendar and making astronomical measuring instruments. Xixia and Dadu controlled water, dug Tonghui River and made a new calendar.

Mathematics: In addition to the progress in astronomical data, Guo Shoujing's calendar method has also made great creation and innovation in calculation methods.

Optics: Guo Shoujing used pinhole imaging principle for many times in astronomical instruments such as landscape symbols and pendulums, which is also an outstanding achievement in the history of optics in China, reflecting the high application ability of optical knowledge in ancient China.

Water Conservancy Science: Xixia Water Conservancy and Dadu River Water Conservancy.

Astronomy: making time calendars

Geography: Guo Shoujing once proposed to compare the differences between Dadu (now Beijing) and Bianliang (now Kaifeng, Henan) based on sea level, which was the creation of an important concept "elevation" in geography.

Reform and invention: astronomical instrument manufacturing; Guo Shoujing's equatorial instrument designed on simple instruments is the earliest equatorial instrument in the world. It was not until A.D. 1598 that the Danish astronomer Tycho invented a similar device in Europe. In Guo Shoujing, roller bearings are used in the simple instrument, so that the moving equatorial ring at the southern end of the simple instrument can flexibly run on the fixed equatorial ring. Similar devices in the west were invented by Italian scientist Leonardo da Vinci 200 years later.

Guo Shoujing and the calendar1spring of 280, when the calendar, the most advanced calendar in the world, was published, it took Guo Shoujing more than four years. In A.D. 128 1 year, Yuan Shizu ordered the nationwide implementation of the service calendar. The chronological method takes 365.2425 days as a tropical year, which is only 26 seconds away from the actual time when the earth goes around the sun, 300 years earlier than the current Gregorian calendar. It abolished the traditional calculation method of "Shang Yuan Chronology" and adopted a simple method of seeking truth from facts, taking the winter solstice of 1280 as the starting point for calculating various astronomical data, which was a great progress in the history of China.

Because it is very accurate in determining the first month, the intersection month and the length, and it has mastered the more accurate orbits of the sun and the moon, and adopted a detailed method, it is very accurate in predicting solar and lunar eclipses. After the publication of "Timing Calendar", it was well received by people. It also traveled across the ocean and was welcomed by North Korea, Japan and other countries.

After the book "Shoushi Calendar" was completed, he began to write books and stand out. At present, there are seven volumes of Home-made Cloth, two volumes of Licheng, three volumes of Yi Li Draft, three volumes of Variable Capacity Selection, and notes on the upper, middle and lower calendars 12. 1286, he was promoted to prefect and dedicated these works to Yuan Shizu. Yuan Shizu was collected in Hanlin National History Institute without reading it.