IAU designated constellations

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IAU designated constellations in equirectangular projection (epoch B1875.0)

In contemporary astronomy, 88 constellations are recognized by the International Astronomical Union (IAU).[1] Each constellation is a region of the sky bordered by arcs of right ascension and declination, together covering the entire celestial sphere. Their boundaries were officially adopted by the International Astronomical Union in 1928 and published in 1930.[2]

The ancient Mesopotamians and later the Greeks established most of the northern constellations in international use today, listed by the Roman-Egyptian astronomer Ptolemy. The constellations along the ecliptic are called the zodiac. When explorers mapped the stars of the southern skies, European astronomers proposed new constellations for that region, as well as ones to fill gaps between the traditional constellations. Because of their Roman and European origins, every constellation has a Latin name. In 1922, the International Astronomical Union adopted three-letter abbreviations for 89 constellations, the modern list of 88 plus Argo. After this, Eugène Joseph Delporte drew up boundaries for each of the 88 constellations so that every point in the sky belonged to one constellation.[1][2]


Some constellations are no longer recognized by the IAU, but may appear in older star charts and other references. Most notable is Argo Navis, which was one of Ptolemy's original 48 constellations. In the 1750s the French astronomer Nicolas Louis de Lacaille divided this into three separate constellations: Carina, Puppis, and Vela.

Modern constellations[edit]

The 88 constellations depict 42 animals, 29 inanimate objects, and 17 humans or mythological characters.


Each IAU constellation has an official three-letter abbreviation based on the genitive form of the constellation name. As the genitive is similar to the base name, the majority of the abbreviations are just the first three letters of the constellation name: Ori for Orion/Orionis, Ara for Ara/Arae, and Com for Coma Berenices/Comae Berenices. In some cases, the abbreviation contains letters from the genitive not appearing in the base name (as in Hyi for Hydrus/Hydri, to avoid confusion with Hydra, abbreviated Hya; and Sge for Sagitta/Sagittae, to avoid confusion with Sagittarius, abbreviated Sgr). Some abbreviations use letters beyond the initial three to unambiguously identify the constellation (for example when the name and its genitive differ in the first three letters): Aps for Apus/Apodis, CrA for Corona Australis, CrB for Corona Borealis, Crv for Corvus. (Crater is abbreviated Crt to prevent confusion with CrA.) When letters are taken from the second word of a two-word name, the first letter from the second word is capitalised: CMa for Canis Major, CMi for Canis Minor. Two cases are ambiguous: Leo for the constellation Leo could be mistaken for Leo Minor (abbreviated LMi), and Tri for Triangulum could be mistaken for Triangulum Australe (abbreviated TrA).[3]

In addition to the three-letter abbreviations used today, the IAU also introduced four-letter abbreviations in 1932. The four-letter abbreviations were repealed in 1955 and are now obsolete, but were included in the NASA Dictionary of Technical Terms for Aerospace Use (NASA SP-7) published in 1965.[4] These are labeled "NASA" in the table below and are included here for reference only.


For help with the literary English pronunciations, see the pronunciation key. There is considerable diversity in how Latinate names are pronounced in English. For traditions closer to the original, see Latin spelling and pronunciation.

Constellation Abbreviations Genitive Origin Meaning Brightest star
IAU[5] NASA[6]
And Andr Andromedae
ancient (Ptolemy) Andromeda (The chained maiden or princess) Alpheratz
Ant Antl Antliae
1763, Lacaille air pump α Antliae
Aps Apus Apodis
1603, Uranometria, created by Keyser and de Houtman Bird-of-paradise/Exotic Bird/Extraordinary Bird α Apodis
Aqr Aqar Aquarii
ancient (Ptolemy) water-bearer β Aquarii
Aql Aqil Aquilae
ancient (Ptolemy) eagle Altair
Ara Arae Arae
ancient (Ptolemy) altar β Arae
Ari Arie Arietis
ancient (Ptolemy) ram Hamal
Aur Auri Aurigae
ancient (Ptolemy) charioteer Capella
Boo Boot Boötis
ancient (Ptolemy) herdsman Arcturus
Cae Cael Caeli
1763, Lacaille chisel or engraving tool α Caeli
Cam Caml Camelopardalis
1613, Plancius[note 1] giraffe β Camelopardalis
Cnc Canc Cancri
ancient (Ptolemy) crab β Cancri
Canes Venatici
/ˈknz vɪˈnætɪs/[8]
CVn CVen Canum Venaticorum
/ˈknəm vɪnætɪˈkɒrəm/
1690, Firmamentum Sobiescianum, Hevelius hunting dogs Cor Caroli
Canis Major
/ˈknɪs ˈmər/[8]
CMa CMaj Canis Majoris
/ˈknɪs məˈɒrɪs/
ancient (Ptolemy) greater dog Sirius
Canis Minor
/ˈknɪs ˈmnər/[8]
CMi CMin Canis Minoris
/ˈknɪs mɪˈnɒrɪs/
ancient (Ptolemy) lesser dog Procyon
Cap Capr Capricorni
ancient (Ptolemy) sea goat δ Capricorni
Car Cari Carinae
1763, Lacaille, split from Argo Navis keel Canopus
Cas Cass Cassiopeiae
ancient (Ptolemy) Cassiopeia (mythological character) α Cassiopeiae
Cen Cent Centauri
ancient (Ptolemy) centaur α Centauri
Cep Ceph Cephei
ancient (Ptolemy) Cepheus (mythological character) α Cephei
Cet Ceti Ceti
ancient (Ptolemy) sea monster (later interpreted as a whale) β Ceti
Cha Cham Chamaeleontis
1603, Uranometria, created by Keyser and de Houtman chameleon α Chamaeleontis
Cir Circ Circini
1763, Lacaille compasses α Circini
Col Colm Columbae
1592, Plancius, split from Canis Major dove α Columbae
Coma Berenices
/ˈkmə bɛrəˈnsz/[8]
Com Coma Comae Berenices
/ˈkm bɛrəˈnsz/[8]
1536, Caspar Vopel,[9] split from Leo Berenice's hair β Comae Berenices
Corona Australis
/kˈrnə ɔːˈstrælɪs, -ˈstr-/[7][8]
CrA CorA Coronae Australis
/kˈrn ɔːˈstrælɪs/
ancient (Ptolemy) southern crown α Coronae Australis
Corona Borealis
/kˈrnə ˌbɔːriˈælɪs, -ˈlɪs/[7][8]
CrB CorB Coronae Borealis
/kˈrn bɔːriˈælɪs/
ancient (Ptolemy) northern crown α Coronae Borealis
Crv Corv Corvi
ancient (Ptolemy) crow γ Corvi
Crt Crat Crateris
ancient (Ptolemy) cup δ Crateris
Cru Cruc Crucis
1603, Uranometria, split from Centaurus southern cross Acrux
Cyg Cygn Cygni
ancient (Ptolemy) swan or Northern Cross Deneb
Del Dlph Delphini
ancient (Ptolemy) dolphin β Delphini
Dor Dora Doradus
1603, Uranometria, created by Keyser and de Houtman dolphinfish α Doradus
Dra Drac Draconis
ancient (Ptolemy) dragon γ Draconis
Equ Equl Equulei
ancient (Ptolemy) pony α Equulei
Eri Erid Eridani
ancient (Ptolemy) river Eridanus (mythology) Achernar
For Forn Fornacis
1763, Lacaille chemical furnace α Fornacis
Gem Gemi Geminorum
ancient (Ptolemy) twins Pollux
Gru Grus Gruis
1603, Uranometria, created by Keyser and de Houtman crane α Gruis
Her Herc Herculis
ancient (Ptolemy) Hercules (mythological character) β Herculis
/ˌhɒrəˈlɒiəm, -ˈl-/[7][8]
Hor Horo Horologii
1763, Lacaille pendulum clock α Horologii
Hya Hyda Hydrae
ancient (Ptolemy) Hydra (mythological creature) Alphard
Hyi Hydi Hydri
1603, Uranometria, created by Keyser and de Houtman lesser water snake β Hydri
Ind Indi Indi
1603, Uranometria, created by Keyser and de Houtman Indian (of unspecified type) α Indi
Lac Lacr Lacertae
1690, Firmamentum Sobiescianum, Hevelius lizard α Lacertae
Leo Leon Leonis
ancient (Ptolemy) lion Regulus
Leo Minor
/ˈl ˈmnər/[7]
LMi LMin Leonis Minoris
/lˈnɪs mɪˈnɒrɪs/
1690, Firmamentum Sobiescianum, Hevelius lesser lion 46 Leonis Minoris
Lep Leps Leporis
ancient (Ptolemy) hare α Leporis
/ˈlbrə, ˈl-/[7]
Lib Libr Librae
ancient (Ptolemy) balance β Librae
Lup Lupi Lupi
ancient (Ptolemy) wolf α Lupi
Lyn Lync Lyncis
1690, Firmamentum Sobiescianum, Hevelius lynx α Lyncis
Lyr Lyra Lyrae
ancient (Ptolemy) lyre / harp Vega
Men Mens Mensae
1763, Lacaille, as Mons Mensæ Table Mountain (South Africa) α Mensae
Mic Micr Microscopii
1763, Lacaille microscope γ Microscopii
Mon Mono Monocerotis
1613, Plancius unicorn β Monocerotis
Mus Musc Muscae
1603, Uranometria, created by Keyser and de Houtman fly α Muscae
Nor Norm Normae
1763, Lacaille carpenter's level γ2 Normae
Oct Octn Octantis
1763, Lacaille octant (instrument) ν Octantis
Oph Ophi Ophiuchi
ancient (Ptolemy) serpent-bearer α Ophiuchi
Ori Orio Orionis
/ˈrənɪs, ˌɒriˈnɪs/[8]
ancient (Ptolemy) Orion (mythological character) Rigel
Pav Pavo Pavonis
1603, Uranometria, created by Keyser and de Houtman peacock α Pavonis
Peg Pegs Pegasi
ancient (Ptolemy) Pegasus (mythological winged horse) ε Pegasi
Per Pers Persei
ancient (Ptolemy) Perseus (mythological character) α Persei
Phe Phoe Phoenicis
1603, Uranometria, created by Keyser and de Houtman phoenix α Phoenicis
Pic Pict Pictoris
1763, Lacaille, as Equuleus Pictoris easel α Pictoris
/ˈpsz, ˈpɪ-/[7][8]
Psc Pisc Piscium
ancient (Ptolemy) fishes η Piscium
Piscis Austrinus
/ˈpsɪs ɔːˈstrnəs/
PsA PscA Piscis Austrini
/ˈpsɪs ɔːˈstrn/
ancient (Ptolemy) southern fish Fomalhaut
Pup Pupp Puppis
1763, Lacaille, split from Argo Navis poop deck ζ Puppis
Pyx Pyxi Pyxidis
1763, Lacaille mariner's compass α Pyxidis
Ret Reti Reticuli
1763, Lacaille eyepiece graticule α Reticuli
Sge Sgte Sagittae
ancient (Ptolemy) arrow γ Sagittae
Sgr Sgtr Sagittarii
ancient (Ptolemy) archer ε Sagittarii
Sco Scor Scorpii
ancient (Ptolemy) scorpion Antares
Scl Scul Sculptoris
1763, Lacaille sculptor α Sculptoris
Sct Scut Scuti
1690, Firmamentum Sobiescianum, Hevelius shield (of Sobieski) α Scuti
Ser Serp Serpentis
ancient (Ptolemy) snake α Serpentis
Sex Sext Sextantis
1690, Firmamentum Sobiescianum, Hevelius sextant α Sextantis
Tau Taur Tauri
ancient (Ptolemy) bull Aldebaran
Tel Tele Telescopii
1763, Lacaille telescope α Telescopii
Tri Tria Trianguli
ancient (Ptolemy) triangle β Trianguli
Triangulum Australe
/trˈæŋɡjʊləm ɔːˈstræl, -ˈstr-/
TrA TrAu Trianguli Australis
/trˈæŋɡjʊl ɔːˈstrælɪs/
1603, Uranometria, created by Keyser and de Houtman southern triangle α Trianguli Australis
Tuc Tucn Tucanae
1603, Uranometria, created by Keyser and de Houtman toucan α Tucanae
Ursa Major
/ˌɜːrsə ˈmər/[7]
UMa UMaj Ursae Majoris
/ˌɜːrs məˈɒrɪs/
ancient (Ptolemy) great bear ε Ursae Majoris
Ursa Minor
/ˌɜːrsə ˈmnər/[7]
UMi UMin Ursae Minoris
/ˌɜːrs mɪˈnɒrɪs/
ancient (Ptolemy) lesser bear Polaris
Vel Velr Velorum
1763, Lacaille, split from Argo Navis sails γ Velorum
Vir Virg Virginis
ancient (Ptolemy) virgin or maiden Spica
Vol Voln Volantis
1603, Uranometria, created by Keyser and de Houtman, as Piscis Volans flying fish β Volantis
Vul Vulp Vulpeculae
1690, Firmamentum Sobiescianum, Hevelius, as Vulpecula cum Ansere fox α Vulpeculae


Various other unofficial patterns exist alongside the constellations. These are known as "asterisms". Examples include the Big Dipper/Plough and the Northern Cross. Some ancient asterisms, for example Coma Berenices, Serpens, and portions of Argo Navis, are now officially constellations.

See also[edit]


  1. ^ The constellations Camelopardalis, Columba, and Monoceros, formed by Petrus Plancius in 1592 and in 1613, are often erroneously attributed to Jacob Bartsch and Augustin Royer.


  1. ^ a b "The Constellations". International Astronomical Union. Archived from the original on 16 December 2020. Retrieved 26 July 2019.
  2. ^ a b Eugène Delporte; International Astronomical Union (1930). Délimitation scientifique des constellations. At the University press.
  3. ^ Russell, Henry Norris (1922). "The New International Symbols for the Constellations". Popular Astronomy. 30: 469. Bibcode:1922PA.....30..469R.
  4. ^ "Constellations". Ian Ridpath. Archived from the original on 16 July 2023. Retrieved 30 January 2023.
  5. ^ "The Constellations". International Astronomical Union. Archived from the original on 16 December 2020. Retrieved 9 December 2015.
  6. ^ NASA Dictionary of terms for Aerospace Use – table V, Constellations
  7. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb bc bd be bf OED, 2nd edition
  8. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb bc bd be bf bg Random House Dictionary
  9. ^ "Comae Berenices". Archived from the original on 24 November 2020. Retrieved 23 November 2020.
  10. ^ "Definition of dorado". Collins English Dictionary. Archived from the original on 28 November 2012. Retrieved 28 November 2012.
  11. ^ Serpens may be divided into Serpens Cauda (serpent's tail) and Serpens Caput (serpent's head), but these disjoint areas are considered part of the same constellation by the IAU.

External links[edit]