Gaocheng Observatory

Location: Dengfeng

Located in Gaocheng Town, the shadow-measuring Plarform and the Astronomical Observatory are not only the oldest observatories in China but also the famous astronomical buildings in the world. It reflects the outstanding achievements of ancient scientists and people in the field of astronomical science.

According to the annals, Zhougong dan, the fourth son of Emperor Zhou wenwang, founded this for measuring the shadow of the sun and testing the changes of the four seasons when he constrcted the east capital Luoyang.

The original sundial was made of clay. In 723 A.D.,it was replaced with a stone one. It's 3.95 metres high. It is also named “No shadow Platform”, because there is no shadow in the surroundings on Summer Solstice.

Through observing for a long time, Zhougong calculated the 24 solar terms. Zhougong Temple was built just for commemorating his devotion.

The observatory of the Yuan Dynasty is the oldest one in China. At the end of 13th centuny, after Emperor Kublaikhan (1216-1294) unified China, he appointed two famous astronomers Guo Shoujing and Wang xun for the reform of the calendar in order to promote the development of agriculture and animal husbandry. 27 observatories were built arround China in 1276年 . And this central one is the only one left.

The observatory is made of two parts, the body and the stone sundial. The platform is 12.62 metres high, and the stone sundial is 31.19 metres long, known “Measuring-the-sky-ruler”.

After four years of observing and calculating, Guo Shoujing mastered the law of the sun, the moon, the stars and the earth, and calculated the precise time of the 24 solar terms. The calendar, named “Shoushi Calendar ”was promulgated to the whole China in 1280.

This calendar is the same as Gregorian calendar, but Shoushi Calendar is 300 years earlier than Gregorian Calendar. It proves the precious devotion of the ancient Chinese people in astronomical science.