Bayer designation - Citizendia

A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name. A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth The Greek alphabet (Ελληνικό αλφάβητο is a set of twenty-four letters that has been used to write the Greek language since the late 9th or early In Grammar, the genitive case or possessive case (also called the second case) is the case that marks a Noun as modifying another In common usage a constellation is a group of celestial bodies that are connected together in some arrangement typically stars to form a visible figure or picture Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. The original list of Bayer designations contained 1,564 stars.

Most of the brighter stars were assigned their first scientific names by the German astronomer Johann Bayer during the early 17th Century, in 1603, in his star atlas Uranometria (named after Urania, the Greek Muse of Astronomy, along with Uranus, the Greek god of the sky and heavens). Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. Historically Astronomy was more concerned with the classification and description of phenomena in the sky while Astrophysics attempted to explain these phenomena Johann Bayer (1572 &ndash March 7, 1625) was a German Astronomer and Lawyer. As a means of recording the passage of Time, the 17th Century was that Century which lasted from 1601 - 1700 in the Gregorian calendar Uranometria is the short title of a star atlas produced by Johann Bayer. In Greek mythology, Urania (Οὐρανία jʊˈreɪnɪə in English which means "heavenly" was the Muse of Astronomy and Astrology In Greek mythology, the Muses ( Ancient Greek, hai moũsai: perhaps from the Proto-Indo-European root * men- "think" are Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study Johann Bayer traveled by sailing ship to various parts of the world, including the southern hemisphere, to conduct his astronomical observations and apply his data. Southern Hemisphere is the half of a Planet that is South of the Equator —the word hemisphere literally means 'half ball' Observation is either an activity of a living being (such as a Human) which senses and assimilates the Knowledge of a Phenomenon, or the recording of data Debt AIDS Trade in Africa (or DATA) is a Multinational non-government organization founded in January 2002 in London by U2 's Bayer assigned a lower-case Greek letter, such as alpha (α), beta (β), gamma (γ), etc, to each star he cataloged. Bayer then attached to each star’s Greek letter the Latin name of the star’s parent constellation in genitive form (or possessive form) to indicate that the star belonged exclusively to that constellation. In Grammar, the genitive case or possessive case (also called the second case) is the case that marks a Noun as modifying another (See List of constellations for a list of constellations and the genitive forms of their names) For example, Bayer assigned the Greek letter alpha (α) to a specific star in the constellation Taurus (the Bull), and added to the star’s Greek letter (α) the name Tauri, which is the genitive form of the Latin name Taurus, to indicate that the star belongs exclusively to Taurus the Bull. Each culture has its own Constellations usually based on Mythology. Taurus (it looks like a bull (ˈtɔrəs bull, symbol, Unicode ♉ is one of the Constellations of the Zodiac. Cattle, colloquially referred to as cows, are domesticated Ungulates a member of the Subfamily Bovinae of the family As a result, the star’s scientific name turned out to be α Tauri (that is to say Alpha Tauri), which means "Alpha of Taurus" or "Alpha of the Bull". A single constellation may contain fifty or more stars, but there are only twenty-four letters of the Greek alphabet, so, when he ran out of Greek letters to use for identifying the stars of a specific constellation, Bayer began using lower-case Latin letters. For example, Bayer assigned three stars in the constellation Carina as s Carinae, and another star in Centaurus as d Centauri, to indicate "s of the Keel" and "d of the Centaur", respectively. Carina ( Keel) is a southern Constellation which forms part of the old constellation of Argo Navis. S Carinae (S Car is a Star in the Constellation Carina. S Carinae is a M-type Red giant with a mean Apparent magnitude Centaurus ( Centaur) is a bright constellation of the southern hemisphere. D Centauri (D Cen is a Binary star in the Constellation Centaurus. Within constellations having an extremely large number of stars, Bayer eventually advanced to upper-case Latin letters, ending with the upper-case letter "Q". For example, Bayer assigned a star in Scorpius the Scorpion the scientific name G Scorpii, which means "G of Scorpius" or "G of the Scorpion". Scorpius ( Latin for Scorpion, symbol, Unicode ♏ is one of the Constellations of the Zodiac. Scorpions are eight-legged Carnivorous Arthropods They are members of the order Scorpiones within the class Arachnida. G Scorpii (G Sco is a Star in the Constellation Scorpius. It is an orange K-type giant with an Apparent magnitude of Another example is a star in Vela the Sails, called N Velorum, which means "N of Vela" or "N of the Sails". Vela (ˈviːlə Sails) is a southern Constellation, one of the three parts into which Argo Navis was split (the others being Carina and A sail is any type of surface intended to generate Thrust by being placed in a Wind &mdashin essence a vertically-oriented Wing. HD 82668 (N Vel / N Velorum is a Star on the border between the Constellations Carina and Vela.

1 Is Alpha Always the Brightest Star?
2 Bayer Designations in Orion
3 Various Bayer Designation Arrangements
4 Revised Bayer Designations
5 Bayer Designation Styles
6 Other Bayer Designations
7 See also

Is Alpha Always the Brightest Star?

For the most part, Bayer assigned Greek and Latin letters to stars in order of apparent brightness, from brightest to dimmest, within a particular constellation. The brightest star in a particular constellation was assigned alpha (α), the second brightest beta (β), the third brightest gamma (γ), and so on. Since the brightest star in many constellations is designated as Alpha (α), many people wrongly assume that Bayer meant to put the stars exclusively in order of their brightness, but in his day there was no way to measure stellar brightness precisely. Traditionally, the stars were assigned to one of six magnitude classes, and Bayer's catalog lists all the first-magnitude stars, followed by all the second-magnitude stars, and so on. However within each magnitude class, there was no attempt to arrange stars by relative brightness. Bayer did not always assign Greek and Latin letters to stars in this manner. Bayer sometimes assigned letters to stars according to their location within a constellation (for example: the northern, southern, eastern, or western part of a constellation), according to the order in which a constellation’s stars rise in the east, according to the historical or mythological information on specific stars within a constellation, or according to his own random choosing. Usually the stars were roughly ordered from the head to the feet (or tail) of the figure (like the stars in the Big Dipper). This article is about the asterism; for other uses see Big Dipper (disambiguation. The conclusion is that Alpha (α) is NOT always the brightest star in a constellation; in fact, of the 88 modern constellations, there are at least 30 constellations in which alpha (α) is not the brightest star, and 4 of those 30 lack an alpha (α) star altogether.

Bayer Designations in Orion

Bayer Designation	Apparent Magnitude	Proper Name
α Ori	0. 45	Betelgeuse
β Ori	0. Betelgeuse (ˈbiːtəldʒuːz or /ˈbɛtəldʒuːz/ ( α Ori α Orionis Alpha Orionis is a Semiregular variable star located 640 Light-years away from 18	Rigel
γ Ori	1. Rigel (ˈraɪʤəl (β Ori / β Orionis / Beta Orionis is the brightest star in the constellation Orion and the sixth brightest star in the sky with Visual 64	Bellatrix
δ Ori	2. 23	Mintaka
ε Ori	1. Delta Orionis (δ Ori traditionally known as Mintaka (from منطقة manţaqah, which means "belt" in Arabic), is a Star some 900 69	Alnilam
ζ Ori	1. Alnilam is a large blue Star in the Constellation of Orion. It also has the modern name Epsilon Orionis (ε Ori / ε Orionis 70	Alnitak

Orion provides a good example of Bayer's method. Zeta Orionis (ζ Ori traditionally known as Alnitak ( Arabic: النطاق an-niṭāq) is a triple star some 800 light years distant in the Orion (ɒˈraɪən a Constellation often referred to as The Hunter, is a prominent constellation one of the largest and perhaps the best-known and most conspicuous (Remember that the lower the magnitude, the brighter the star. Additionally a "2nd-magnitude" star has a more precise magnitude between 1. 51 and 2. 50, inclusive. ) Bayer first designated the two 1st-magnitude stars, Betelgeuse and Rigel, as Alpha and Beta, with Betelgeuse (the shoulder) coming ahead of Rigel (the foot), even though the latter is the brighter.

He then repeated the procedure for the stars of the 2nd-magnitude. As is evident from the map and chart, he again followed a "top-down" ("north-south") route.

The belt of Orion is composed of three bright stars Delta Orionis, Epsilon Orionis and Zeta Orionis, however, the brightest star in the belt is not delta but epsilon. Delta Orionis (δ Ori traditionally known as Mintaka (from منطقة manţaqah, which means "belt" in Arabic), is a Star some 900 Alnilam is a large blue Star in the Constellation of Orion. It also has the modern name Epsilon Orionis (ε Ori / ε Orionis Zeta Orionis (ζ Ori traditionally known as Alnitak ( Arabic: النطاق an-niṭāq) is a triple star some 800 light years distant in the Instead, Bayer named the stars of Orion's belt in the special order in which they rise in the east, first delta (δ), then the middle star epsilon (ε), then zeta (ζ).

Various Bayer Designation Arrangements

This "First to Rise in the East" method is done in a number of other instances, even for Castor and Pollux of Gemini. Castor (α Gem / α Geminorum / Alpha Geminorum is the second brightest star in the Constellation Gemini and one of the brightest stars in the Pollux, also cataloged as Beta Geminorum (β Gem / β Geminorum is an Orange giant Star approximately 34 Light-years away in the Constellation Gemini (ˈgɛmɪnaɪ Twins, symbol, Unicode ♊ is one of the Constellations of the Zodiac known as "the twins" Although Pollux is brighter than Castor, the latter was assigned alpha because it rises in the east ahead of the former. Bayer may also have assigned the stars Castor and Pollux in terms of historical or mythological knowledge. Both historically and mythologically, Castor's name is almost always mentioned first (Castor and Pollux) whenever the twins are mentioned, and that may have compelled him to assign alpha (α) to Castor and beta (β) to Pollux.

Although the brightest star in Draco is Eltanin (Gamma Draconis), Thuban was assigned alpha (α) by Bayer because Thuban, in history, was once the North Star 4,000 years ago. Gamma Draconis (γ Dra / γ Draconis is a Star in the Constellation Draco. This article is about the Star Th'uban is an Arabic word for Dragon. Almost every star with a history of being the North Star, including Vega, Alderamin and Polaris, were designated as the alpha (α) of their parent constellations by Bayer. The North Star is the prominent Pole star that lies closest in the sky to the north celestial pole and which appears (approximately directly overhead to Vega (α Lyr / α Lyrae / Alpha Lyrae ( or) is the brightest Star in the Constellation Lyra, the fifth brightest star in the night Alpha Cephei (α Cep / α Cephei is a Star in the Constellation of Cepheus. Polaris (α UMi / α Ursae Minoris / Alpha Ursae Minoris commonly North(ern Star or Pole Star, and sometimes Lodestar

Sometimes, indeed, there's no apparent order, as exemplified by the stars in Libra and Sagittarius, where Bayer assigned designations to stars at random. Libra (ˈliːbrə balance, symbol, Unicode ♎ is a Constellation of the Zodiac. (The letters of the Greek alphabet were used in antiquity to represent the successive integers; so Bayer's scheme might be regarded as equivalent to a numbering system. )

Revised Bayer Designations

When the International Astronomical Union (IAU) outlined the official 88 constellations with definite boundaries in 1930, some stars became borderlined between constellations. The International Astronomical Union (IAU) declared that stars and other celestial objects can be assigned to only one constellation. Consequently, these borderlined stars that lie very close to constellation boundaries were reassigned to one new official constellation and were given new Bayer designations in the process. For example, β Tau, formerly known as (γ Aur), and α And, formerly known as (δ Peg). Beta Tauri (β Tau / β Tauri is the second brightest Star in the Constellation Taurus, with Apparent magnitude 1 Alpha Andromedae ( Alpha And / α And / α Andromedae) which also has the traditional names Alpheratz and Sirrah (alternately Another star, σ Lib, was formerly known as γ Sco; however it is not on the boundary of Libra and Scorpius but well inside Libra. Sigma Librae (σ Lib / σ Librae is a Star in the Constellation Libra. Libra (ˈliːbrə balance, symbol, Unicode ♎ is a Constellation of the Zodiac. Scorpius ( Latin for Scorpion, symbol, Unicode ♏ is one of the Constellations of the Zodiac. In addition, there are even cases where a star has a designation for a constellation in which it does not lie (according to the modern constellation boundaries). Nonetheless, these designations have proved useful and are widely used today.

Bayer Designation Styles

There are two common ways in which Bayer designations can be written. The designation can be written out in full, as in Alpha Canis Majoris or Beta Persei, or a lowercase Greek letter can be used together with the standard 3-letter abbreviation of the constellation, as in α CMa or β Per. Sirius is the brightest star in the night sky with a visual Apparent magnitude of &minus1 Algol (β Per / Beta Persei known colloquially as the Demon Star, is a bright Star in the Constellation Perseus. Earlier 4-letter abbreviations (such as α CMaj) are rarely used today.

Other Bayer Designations

The Latin letter extended designations are rarely used, but there are some exceptions such as h Persei (which is actually a star cluster) and P Cygni. NGC 869 is an Open cluster located 6800 Light years ref name="Kharchenko" /> away in the constellation of Perseus. Star clusters are groups of Stars which are gravitationally bound P Cygni is a Variable star in the Constellation Cygnus. It is a Hypergiant Luminous blue variable (LBV star of spectral Note that uppercase Latin Bayer designations never went beyond Q, and names such as R Leporis and W Ursae Majoris are variable star designations, not Bayer designations. W Ursae Majoris ( W UMa) is a Variable star in the Constellation Ursa Major. Variable stars are named using a variation on the Bayer designation format of an identifying label (as described below combined with the Latin genitive

A further complication is the use of numeric superscripts to distinguish between stars with the same Bayer letter. Usually these are double stars (mostly optical doubles rather than true binary stars), but there are some exceptions such as the chain of stars π¹, π², π³, π⁴, π⁵ and π⁶ Orionis. Double Star is a Science fiction Novel by Robert A Heinlein, first serialized in Astounding Science Fiction A binary star is a Star system consisting of two Stars orbiting around their Center of mass. Pi3 Orionis (π3 Ori / π3 Orionis formally designated Tabit, is a Yellow-white dwarf Star approximately 26 Pi4 Orionis (&pi4 Ori / &pi4 Orionis is a Spectroscopic binary Star in the Constellation Orion. Pi Orionis (&pi Ori / &pi Orionis is a group of fairly widely scattered Stars in the Constellation Orion that constitute Orion's shield

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