Purple Mountain Observatory
Nanjing, Jiangsu, PRC

7. Abridged Armilla

At the beginning of the Yuan Dynasty, astronomer Guo Shou-jing simplified the complicated ancient instrument so as to separate the circles of the horizontal coordinate system from those of the equatorial system. It can avoid the obscuration of the observable sky region by the many rings of the old instrument. It is a copy made in 1437, the second year of the Zheng-Tong Reign of the Ming Dynasty.