Chinese constellations

Chinese constellations are the way ancient Chinese grouped the stars. They are very different from the modern recognized constellations, which were based on Greek astronomy, or the Nakshatras of the Indian astronomy. This is due to the independent development of ancient Chinese astronomy.



Ancient Chinese skywatchers divided their night sky into 31 regions, namely Three Enclosures and Twenty-eight Mansions . The Three Enclosures occupy the area close to the North Celestial Pole. The stars in the Three Enclosures can be seen all year around.



The Twenty-eight Mansions occupy the zodiac region of the sky. They can be considered as the equivalent to the 12 zodiacal constellations in the Western Astronomy. Contrary to the Western Astronomy, the Twenty-eight Mansions reflect the movement of the Moon in a lunar month rather than the Sun in a Solar Year.



The Three Enclosures and the Twenty-Eight Mansions are further divided into 23 s. Each visible star is assigned into one of the asterisms. Some of the asterisms only have one star. Traditionally, a star is named by combining the name of its asterism with a number.

Three Enclosures

The Three Enclosures are the Purple Forbidden enclosure , the Supreme Palace enclosure and the Heavenly Market enclosure . The Purple Forbidden Enclosure occupies the northernmost area of the night sky. From the viewpoint of the ancient Chinese, the Purple Forbidden Enclosure lies in the middle of the sky, and is circled by all the other stars.



The Supreme Palace Enclosure lies east and north to the Purple Forbidden Enclosure, while the Heavenly Market Enclosure lies west and south. The Three Enclosures are separated by "walls", which are asterisms with their shapes resembling their namesakes.

The Twenty-Eight Mansions

The zodiac is listed below,

The Southern Asterisms

The sky around the south celestial pole was unknown to ancient Chinese. Therefore, it was not included in the Three Enclosures and Twenty-Eight Mansions system. However, by the end of the Ming Dynasty, Xu Guangqi introduced another 23 asterisms based on the knowledge of western star charts. These asterisms were since incorporated into the traditional Chinese star maps.

Chinese Star Designation

Ancient Chinese astronomers designated names to the visible stars systematically, roughly more than one thousand years before Johann Bayer did it in a similar way. Basically, every star is assigned to an asterism. Then a number is given to the individual stars in this asterism. Therefore, a star is designated as "Asterism name" + "Number". The numbering of the stars in an asterism, however, is not based on the apparent magnitude of this star as in Bayer designation, but rather its position in the asterism.



For example, Altair is named 河鼓二 in Chinese. 河鼓 is the name of the asterism . 二 is the number designation . Therefore it literally means "the Second Star of the Drum at the River.



Some stars also have traditional name, often related with mythology or astrology. For example, Altair is more commonly known as 牛郎星 or 牵牛星 in Chinese, after the mythologic story of Cowherd and Weaver Girl.



These designations are still used in modern Chinese astronomy. All the stars using the traditional name in English are routinely translated with traditional Chinese designations, instead of the translation of its catalogue names.