Xuanyuan highlighted on the Suzhou star chart

Xuanyuan is the name of the Yellow Emperor. In Chinese astrology, it is a constellation/ asterism symbolizes the body of a yellow dragon. It consists of 17 stars in the area of Leo and Lynx.

Etymology & History of the term

The Yellow Emperor is a legendary figure in China. It is unknown whether or not the "persona" goes back to a real ruler of the country in the 3rd millennium or is completely invented. In the 20th century, this figure was made a symbol for the creator of the state of China and bringer of civilization.

In astrology, it mainly represents the concubines of the Yellow Emperor's harem. Based on the brightness and position of these stars, ancient astrologers named them after different ranks of concubines, mong which the most important is the Nüzhu, representing the emperor's primary wife (the queen), alf Leo. In terms of form, this star also represents the head of the Yellow Dragon, while the stars on the left and right represent its horns (rho, omicron).

Ian Ridpath's webpage on Leo has more information.

Historical Maps

As one of the oldest Chinese constellations, Xuanyuan is depicted on many historical star charts from China.

Lost ones

The Location of Nüshi in Xuanyuan

A weishu book from the western Han Dynasty (1st century BCE), titled Xiao Jing · Yuan Shen Qi (孝经·援神契), mentions a kind of Xuanyuan constellation with only 12 stars, compared to the current one with 17 stars. It is possible because the current Xuanyuan constellation includes several very faint stars. Since star maps from that time no longer exist, we cannot determine the specific configuration of these twelve stars. However, according to records, we know that it at least included the prominent/determinative star Nüzhu(Queen, alf Leo), Furen (higher concubine, eta Leo) and Yunü (lower concubine, 31 Leo).^[1] This early variant of Xuanyuan should be consistent with the 17-star form regarding the stars in the southern region.

The Huangdi (Yellow emperor)'s Divination is a book that possibly originated during the Han Dynasty. It records a kind of Xuanyuan constellation with also 17 stars, but in its account, Xuanyuan consists of another small star called Nüshi (Female historian, pi Leo) at the south of the Yunü star (called "Huangzi (a prince)" by this book) with a distance of 2 degrees.

Identification of stars

The numbering of stars has undergone changes. The numbering system popular today is developed by missionaries in the Qing Dynasty, starting from the northernmost star (10 UMa) of the Xuanyuan constellation for coding, which is contrary to the traditional Chinese practice, which should be counted northwards fron the determinative star (from 1 to 14, while the rest 3 stars at the southernmost were already named).

Preserved Images

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  constellation Xuanyuan on the Suzhou Star Chart (created in 1247, retrieved from https://www.chinesehsc.org/zoomify/suzhou_planisphere.html)

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  Xuanyuan on the Korean Star Chart (7th century or before)

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  Xuanyuan in the Xinyixiangfayao Star Map from Su Song(苏颂, 1020-1101 AD).

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  Xuanyuan mapped in Stellarium 2024 by Boshun Yang (2023)

Star Name Discussion (IAU)

Europeans in the IAU WGSN proposed in 2023/4 to use the name "Xuanyuan" for any star in this area, for instance, apply it to the star "alf Lyn" in the IAU-Catalog of Star Names (CSN).

The Chinese members of IAU WGSN considered "Xuanyuan" too important in Chinese Culture and refused to apply this name to any other than the determinative star. Hence, the only proper star for this name would be alpha Leonis which is already named "Regulus". Therefore, the IAU WGSN decided to not use "Xuanyuan" as a name of any stars. Hitoshi Yamaoka summarizes that this is the same case as Vega/Orihime. Such name should not used for any other star.

References

References (Chinese)