Luoxia Hong (, c. 130–70 BCE) was a Chinese astronomer during the Western Han dynasty. A folk astronomer from
southwest China
Southwestern China () is a region in the People's Republic of China. It consists of five provincial administrative regions, namely Chongqing, Sichuan, Guizhou, Yunnan, and Xizang.
Geography
Southwestern China is a rugged and mountainous region, ...
, Hong was one of over twenty astronomers who traveled to
Chang'an
Chang'an (; zh, t=長安, s=长安, p=Cháng'ān, first=t) is the traditional name of the city now named Xi'an and was the capital of several Chinese dynasties, ranging from 202 BCE to 907 CE. The site has been inhabited since Neolithic time ...
(now
Xi'an
Xi'an is the list of capitals in China, capital of the Chinese province of Shaanxi. A sub-provincial city on the Guanzhong plain, the city is the third-most populous city in Western China after Chongqing and Chengdu, as well as the most populou ...
) to propose a new calendar system for
Emperor Wu.
It was not uncommon for emperors to introduce new calendars in order to place greater emphasis on heavenly bodies that were seen as particularly astrologically relevant to the particular ruler,
but this reform was of such a scale that it was called the "Grand Inception" (太初) in contemporary documents. The calendar made by Hong and his associate Deng Ping was accepted over that of other contestants, including several imperial astronomers.
It included 12 months of 29 or 30 days, with an additional month in seven out of 19 years.
It also included precise calculations for the movement of the sun, moon, planets, and the time of eclipses, which Hong was able to predict using an equatorial
armillary sphere
An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (on the celestial sphere), consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines o ...
which he significantly improved,
or possibly even invented.
The ''Tai Chu'' lunisolar calendar went into effect in 104 BCE, and remained substantially unchanged for nearly 2,000 years.
Emperor Wu offered Hong an official position at court, but Hong declined and returned to solitary life.
See also
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History of Chinese Calendars
*
Chinese armillary spheres
*
Yu Xi
Yu Xi (虞喜; 307–345 AD), courtesy name Zhongning (仲寧), was a Chinese astronomer, politician, and writer of the Jin dynasty (266–420 AD). He is best known for his discovery of the precession of the equinoxes, independently of the earlie ...
*
Zhang Heng
Zhang Heng (; AD 78–139), formerly romanization of Chinese, romanized Chang Heng, was a Chinese polymathic scientist and statesman who lived during the Han dynasty#Eastern Han (25–220 AD), Eastern Han dynasty. Educated in the capital citi ...
References
{{DEFAULTSORT:Luoxia, Hong
130s BC births
70s BC deaths
Year of birth uncertain
Year of death uncertain
2nd-century BC Chinese astronomers
1st-century BC Chinese people