Star naming

The International Astronomical Union (IAU) is the internationally recognized authority in astronomy for assigning names to stars and other celestial bodies . Many of the star names known today come from the time before the IAU was founded. Other names, mostly for variable stars including novae and supernovae , are constantly being added. Most of the innumerable stars, however, have no name and are identified - if at all - with the help of catalog numbers. The following is a brief overview of various methods of star naming ( astronymy ).

Proper names

Many of the brighter stars or stars that are interesting for other reasons have proper names. Most come from Arabic , such as B. Algol or Ras Algethi , but there are also some with Latin names, such as Polaris or Regulus , and some have German names in addition to the Arabic or Latin ones , such as the dog star or the little rider . Some stars are named after their discoverers, such as Barnard's Arrow Star or Kapteyn's Star .

See also: List of star names - a list of known historically determined proper names

See also: List of German words from Arabic - with the exact origin of the name ( etymology ) of important stars

The IAU has been cataloging and standardizing the proper names of stars since 2016, and these are then published in the IAU Catalog of Star Names (IAU-CSN) . By September 7, 2018, a total of 336 proper names were recorded. The catalog is constantly being expanded. In addition, the IAU Working Group on Star Names (WGSN) publishes the catalog expansions collected at regular intervals.

Bayer / Flamsteed Code

The nomenclature for the clear-sighted stars follows a scheme as in Alpha Centauri after the constellation of the centaur .

Johann Bayer introduced this still widespread system of naming the brighter stars of each constellation using Greek and occasionally Latin letters. This is explained in more detail in the article on Bayer names . According to the Bayer designation, the brightest star of the respective constellation is designated α, the second brightest β, and so on.

John Flamsteed devised a similar system by numbering the stars of the constellations, but arranging the numbers according to right ascension . Today it is mostly used where there is no Bayer name and is described in the article on Flamsteed names . The Flamsteed catalog contains 2554 stars that were visible from the south of England during the creation of the catalog; thus stars of the southern sky are hardly represented.

Naming variable stars

Variable stars without Bayer designation are given special designations. The first variable within a constellation is called R, the next S, then T and so on (e.g. R Doradus ). When this was no longer sufficient with the improved astrophotographic possibilities, two-digit designations were introduced (e.g. VY Canis Majoris ). Nowadays, newly discovered variables are numbered consecutively with a preceding V (e.g. V452 Scuti ). This system is explained in more detail in the article on naming variable stars .

Catalog numbers

In the absence of a better method of naming a star, catalog numbers from the major star catalogs are generally used. With the myriad of stars that are only known in our Milky Way galaxy , this is the only practically feasible procedure that also ensures unambiguous identification and retrieval in a uniform manner. For this purpose, there are many different star catalogs, some of which have been compiled by observing astronomers , but some have also been collected in automatic surveying projects by special satellites and large observatories . While the Hipparcos catalog numbers the objects consecutively, the objects in the Two Micron All Sky Survey are named after their right ascension and declination.

Star naming

It should also be noted that there are some companies and also observatories that offer customers to name stars according to their wishes. When a star is named, a star identified by a catalog number with a self-chosen name is usually given for money. However, these terms have no scientific or official meaning and only exist in the company's own list or website and on a printout provided to the customer. So it is a purely symbolic gesture that basically anyone can perform themselves.

See also

• Naming variable stars
• Chinese star constellations - to the traditional, but still common nomenclature of Chinese astronomy
• Messier Catalog (M), New General Catalog (NGC), Index Catalog (IC), Perek Kohoutek Catalog (PK) - for naming other astronomical objects such as galaxies, star clusters and nebulae

Web links

• Official IAU statement on the “purchase of stars” and German translation .

Individual evidence

1. ^ IAU Catalog of Star Names. Retrieved on August 16, 2019 . 
2. ^ Working Group on Star Names (WGSN). Retrieved November 11, 2016 .