Yu Xi's precession of the equinoxes
Precesión de los equinoccios de Yu Xi
- Date
- c. 330 · confidence medium
- Place
- Jiankang (Nanjing), Jiangsu, China
- Credited to
- Yu Xi
- People
- 👤 Yu Xi
- Field
- Cosmos & Earth
What was discovered
Yu Xi compared winter solstice positions recorded over centuries and concluded that the point shifts by one degree every 50 years. He introduced the correction into the calculation of the Chinese calendar.
An independent discovery from Hipparchus's (c. 130 BCE); the Chinese value (1°/50 years) is less accurate than the real one (1°/72 years).
What it led to
- correction of precession in Zu Chongzhi's Daming calendar (463)