In recent years, various services have emerged through which people can have the opportunity to name a star in honor of themselves or someone they love. With these services, users can honor a loved one or caress their own egos, but this has no bearing on the astronomical community. Over the centuries, the methods for naming stars have changed and, currently, it is the International Astronomical Union (IAU) that governs these methods. In some cases, stars have proper names, while in others, they are named because of their brightness and, in others, because of their position within the constellation. Below, you will find an explanation of how the names of the stars are determined.
Method 1 of 2: Give a Star a Proper Name
Step 1. Give a star a proper name according to its mythological meaning
Many constellations are associated with myths or legends and, in the same way, the stars within these constellations were named after the myths to which they were associated.
- The constellation Gemini represents the twin children of Queen Leda of Sparta, whom the death of one of them failed to separate. The twins' names were Castor and Pollux, which are also the names of the two brightest stars in this constellation.
- The seven brightest stars in the Pleiades represent the seven daughters of Atlas and Pleyone, whom Orion pursued: Alcíone, Celeno, Electra, Maia, Merope, Sterope and Taygeta, in whose honor these stars were named.
- Sirius, the proper name for the brightest star in the constellation Can Major, means "scorching" or "fiery" and is derived from the ancient Egyptians' belief that Sirius contributed its heat to that of the sun when it rose along with him in early August. Sirius's nickname is "the dog star."
- It is also possible that the proper name of a star is derived from a myth that differs from that of the constellation in which the star is found. The star Alkaid was perceived among the ancient Egyptians as the one leading a funeral procession, which is why they gave it this name. However, this star is in the constellation Ursa Major, which the Greeks perceived as a bear.
Step 2. Give a star a proper name based on its position in the sky or in the constellation
In many cases, the proper names of the stars come from their position within their own constellation or an adjacent constellation.
- The name of the bright star Deneb in the constellation Cygnus comes from the Arabic word for "tail", since this star represents the tail of the swan. Similarly, the star Denébola in the constellation Leo represents the tail of the lion, while the star Deneb Kaitos in the constellation Ceto represents the tail of the whale.
- "Betelgeuse" means "armpit" and "Rigel" means "foot" in Arabic, so the stars with these names constitute, respectively, the right armpit and the left foot of the constellation Orion.
- Arturo, the name of the star in the constellation El Boyero, means "conducting bear" as it follows the constellations Ursa Major and Ursa Minor as they orbit the north celestial pole.
Step 3. Give a star a proper name based on its astronomical properties
In some cases, the proper names for stars come from properties that astronomers were able to observe with the naked eye or through primitive lenses.
- The star Algol in the constellation Perseus gets its name from the Arabic word "al ghul", which means "demon" or "evil spirit". This is an eclipsing binary star that has a dimmer appearance when the dimmest star is closer to Earth than the brightest star and represents the head of Medusa, the gorgon whom Perseus killed.
- The star Mira in the constellation Keto gets its name from the Latin word for "wonderful", which has the same root as the word for "miracle." This is a variable star and undergoes changes in brightness over a regular period of time.
Step 4. Give a star a proper name for other reasons
In modern star registries, people are allowed to give stars unofficial names in honor of themselves or their loved ones, but there are some stars that were given official names for similar reasons. For example, the star Cor Caroli in the constellation Canes Venatici was named after King Charles II of Great Britain and means "the heart of Charles."
Method 2 of 2: Other Methods for Naming a Star
Step 1. Name them according to their brightness within the constellation
Around 1600, the German astronomer Johannes Bayer developed the first modern system for naming stars according to their apparent brightness within the constellation. To do this, he used Greek letters with which he classified the stars from the brightest to the dimmest ("alpha" being the brightest and "omega" the dimmest) followed by uppercase and lowercase Roman letters after they ran out. Greek letters. The name of a star was made up of its classification as to its brightness and the possessive form of its name. So, according to the Bayer system, the brightest star within the constellation The Centaur was called Alpha Centauri.
- Using the Bayer system, stars were not always named exclusively according to their brightness, but sometimes the position of the star within the constellation was also taken into consideration. According to Bayer, Castor was designated as "Alpha Geminorum" and Pollux as "Beta Geminorum", even though the latter is actually brighter than Castor. This is because, in the sky, Castor appears in the upper right of Pollux.
- Later, modifications were made to the Bayer method and letters were added after the names of the stars to designate individual stars within a multiple star system, such as Alpha Centauri A and Alpha Centauri B, as well as numbers for designate the magnitude indicator, such as Pi1 Orionis, Pi2 Orionis, etc.
Step 2. Name a star according to its position within the constellation
According to the Flamsteed method, which John Flamsteed developed in the 18th century, the star at the western end of the constellation was given the number 1, the next star the number 2, and so on, using the possessive name as a suffix. Therefore, following this system, the star at the western end of the constellation Leo would be designated as 1 Leonis.
Bayer and Flamsteed naming conventions are often used in conjunction with proper names. For example, if a star has a proper name, it is often known by this name. Otherwise, your Bayer name is used. If you do not have a proper name or a Bayer name, your Flamsteed number is used. Alpha Centauri is the main exception to this rule, as this star is known by its Bayer name rather than by its proper name, Toliman (and is known to aviators and sailors as Rigel Kentaurus)
Step 3. Name a star according to its right ascension and declination regardless of the constellation to which it belongs
The system of proper names, Bayer names, and Flamsteed numbers favored the brightest stars and ignored the large number of dimmer stars, so another method was needed to classify all the stars that existed in the world. night sky. Using this method, stars are classified according to their right ascension, their distance from the vernal equinox, and their declination from the celestial equator. According to these classifications, the sky is usually divided into stripes of either right ascension (celestial longitude) or declination (celestial latitude), and then the stars within these stripes are listed.
- The Harvard Revised Bright Star Catalog, which is now edited by Yale University, lists 9,000 stars down to the sixth magnitude from west to east. According to this catalog, the star Vega within the constellation of Lyre is known as HR 7001.
- The 19th century Bonner Durchmusterung ("The Bonn Compilation") covered the stars that were visible in the northern sky down to the tenth magnitude and divided each degree of declination into a strip. According to this catalog, the star Vega would be designated as BD38 3238. (There was also a complementary compilation, the Cordoba Durchmusterung or "The Cordoba compilation", which covered the southern sky).
- Today the most commonly used star catalog is Henry Draper's. Here, the stars are numbered solely according to their right ascension, whereby the star Vega has the designation HD 172167. Other star catalogs include the Smithsonian SAO Catalog and the international Hipparcos catalogs. According to these, the star Vega is known as SAO 067174 and HIC 91262, respectively.
- Some stars may have been given various proper names. Alkaid, in Ursa Major, is also often known as Benetnasch, while Alpheratz in the constellation Andromeda is also often known as Sirrah. The UAI is the one who determines what is the preferred proper name.
- Note that stellar catalogs that are based on the positions of the stars in the sky must undergo periodic reviews due to the precession of the Earth's axes and the proper motion of the stars relative to each other in the galaxy. In catalogs of this type, the position of the star or the vernal equinox is usually specified from a certain date.