Honui and Ganui, Sejong's armillary spheres
Honui y Ganui, esferas armilares de Sejong
- Date
- 1432-1438 · confidence medium
- Place
- Gyeongbokgung Palace, Seoul, South Korea
- Credited to
- Jeong Cho, Yi Cheon, Jeong In-ji and Jang Yeong-sil
- Field
- Cosmos & Earth
What it is
A bronze armillary sphere with rings for measuring equatorial coordinates (Honui) and the Ganui, a simplified version with some rings removed for easier observation. They were installed at the Gyeongbokgung observatory for official astronomical measurements.
They build on the Chinese design by Guo Shoujing (Jianyi, 1276), simplified by Sejong's astronomers. Years vary by source (chronicles give 1432, 1433 and 1438 for different parts of the set).
What it led to
- observations for the Chiljeongsan and Korea's calendar reform
- the Gancheondae observatory in Seoul
- the later Joseon armillary clock tradition