Constellation Names and Abbreviations

Most of the well-known star constellation names date back to ancient Greece or earlier, but the precise list remained somewhat fuzzy until the early 20th century. Then, in a series of resolutions from 1922 to 1930, the International Astronomical Union (IAU) divided the celestial sphere into 88 precisely defined constellations with official spellings and abbreviations.

Every constellation name has two forms: the nominative, for use when you're talking about the constellation itself, and the genitive, or possessive, which is used in star names. For instance, Hamal, the brightest star in the constellation Aries (nominative form), is also called Alpha Arietis (genitive form), meaning literally "the Alpha of Aries." When space is at a premium, this is written α Ari, using the lower-case Greek letter alpha and the abbreviation for Aries.

Constellation Names

The table below lists all 88 constellations in alphabetical order. If you don't want to scroll through the whole thing, click on the appropriate abbreviation in the index table. Click on the pronunciations in the main table to hear what they really sound like. After the table, there are extended discussions of the constellations' history, their names and meanings, and their pronunciations.

¹The ancient constellation Argo Navis was split into Carina, Puppis, Pyxis, and Vela in the 18th century.

²In 1932 the IAU officially changed this constellation's name from Corona Australis to Corona Austrina (genitive Coronae Austrinae), but the revised name never really caught on. The original name is used far more often, and even the IAU website implicitly endorses it as an alternative.

³Australe, Australis, and Borealis are sometimes prounced aw-STRAIL-ee, aw-STRAIL-iss, and bor-ee-AIL-iss, respectively.

⁴Ophiuchus and Serpens used to share several stars. The IAU reforms assigned the shared stars to Ophiuchus, leaving Serpens in two disjoint pieces: Serpens Caput (the Serpent's Head) and Serpens Cauda (the Serpent's Tail).

⁵Before the IAU reforms, astronomers used the names Scorpius and Scorpio interchangeably. Scorpio is now used primarily by astrologers.

⁶Tucana and Tucanae are sometimes pronounced tyoo-KAY-nuh and tyoo-KAY-nee, respectively.

Constellation Origins

Star constellations are human inventions, not things that really exist "out there" in the sky. Different cultures have divided and organized the stars and deep sky objects in very different ways, though a few patterns (notably true physical clusters like the Pleiades) are so eye-catching that they're nearly universal. The constellations recognized by scientists today are the ones that arose out of the European tradition.

The major European constellation names are very old. A few, notably the Great Bear, are widely believed to predate the invention of writing some 5,000 years ago. And there's compelling evidence that many, including the zodiacal constellations, originated in Mesopotamia sometime before 1,000 BC. Somehow, the Mesopotamian constellations were imported into ancient Greece, but there's no record of how or why this occurred. As for timing, the Mesopotamian constellations were not mentioned in the works of Homer and Hesiod (about 700 BC), but they were firmly entrenched in the earliest comprehensive Greek constellation lists, which appeared around 350 BC.

The Greeks seem to have invented some constellations of their own, notably the Perseus family, around the same time that they adopted the Mesopotomian constellations, and a few more were added after 350 BC. The comprehensive list of ancient constellations appeared in a book written around AD 150 by the Greco-Egyptian astronomer Claudius Ptolemy. This book, which summarized all of classical astronomy, is now known by its (entirely appropriate) Arabic name: Almagest, meaning "the Greatest."

Astronomy was neglected in Europe for more than a millennium following the Almagest, but it revived in the 15th century, when European navigators started to explore unknown waters. When these sailors ventured south of the equator, they saw stars that were not in Ptolemy's catalog and organized them into new constellations. Later, in the telescopic era, astronomers invented additional constellations to fill the gaps between the traditional ones — areas that were uninteresting to Ptolemy and the early European navigators because they contain no bright stars.

Rome conquered the entire Greek-speaking world by 30 BC, and the Greek constellation names were translated or transliterated into Latin, the primary language of the Roman Empire. Latin has remained the standard language for scientific nomenclature ever since. That's why all constellations invented since classical times have Latin names, as do all species of plants and animals.

Names and Nicknames

Most constellation names are simple common nouns with obvious English equivalents. For instance, Leo is Latin for "the lion" or "a lion." The Greeks sometimes tried to associate the constellation Leo with some particular lion from their mythology, but there's every reason to believe that when they inherited this constellation from Mesopotamia, it was just a generic lion. Or, more precisely, the great celestial Lion — the Lion that Lives in the Sky.

Other constellations are named after specific people or things. For instance, Eridanus is one particular mythological river, not the Latin equivalent of "a river" or "the river." The constellation Perseus is often nicknamed the Hero in English, but this is a little misleading, as that nickname could apply equally well to Hercules.

Not surprisingly, there are plenty of intermediate cases. Thus, Cetus means just a sea monster, whale, or large fish, but it's very likely that the constellation's inventor was thinking of the particular monster that tried to eat Andromeda. And Gemini is the common Latin word for "twins" but also the special epithet of the mythological twins Castor and Pollux.

Some sky atlas guides will use one variation of a constellations name while others may use another so be keep this in mind when using this reference guide.

Pronunciations

Our pronunciations of constellation names are drawn from four sources:

1. The article Pronouncing Astronomical Names by George A. Davis, Samuel G. Barton, and I. McHugh, Popular Astronomy. August 1942.
2. The American Heritage Dictionary, 4th edition.
3. Celestial Objects for Modern Telescopes by Michael A. Covington, pages 80–84.
4. Usage polls of Sky & Telescope editors.

Pronouncing Astronomical Names was the report of a committee of the American Astronomical Society (AAS) charged with standardizing the pronunciation of constellations and stars. Sky & Telescope republished the constellation pronunciations several times, first in the June 1943 issue and most recently (with minor modifications) in the article Designated Authority by E. C. Krupp, May 1997, page 66. The AAS pronunciations were the S&T standard until 2004, when the desire to include pronunciation guides in Night Sky magazine forced us to reexamine the entire subject.

In fact, the AAS report is deeply flawed. It was inspired by the IAU's standardization of constellation definitions, but that was a very different situation. The IAU reforms were successful because they addressed an urgent need. Newly discovered variable stars are named after the constellation that contains them, and this only works if everyone agrees on the constellation boundaries. There's no comparable reason to standardize pronunciation. Experienced astronomers, both professional and amateur, pronounce constellation names in many different ways but have no trouble understanding each other. Moreover, the pronunciations chosen for the AAS report were somewhat arbitrary. There are several well-defined systems for pronouncing Latin, and the AAS pronunciations don't conform with any of them.

What's worse, the AAS report clashes with common usage in several important cases. Even at Sky & Telescope, which has been eager to promote the AAS standard, not a single editor pronounces Pisces as piss-ease, in accordance with the AAS recommendations. Nonetheless, having told people for generations that they can't go wrong with the AAS pronunciations, we've made sure that they're all included in the table above, though not necessarily as the first choice.

The American Heritage Dictionary (AHD) lists all but two of the constellations, with one or more pronunciations specified for each. It's much more faithful to actual American usage than the AAS report. We've included all of the AHD pronunciations of constellation names except for a few minor variants.

Michael Covington is a professional linguist with a solid grounding in Greek and Latin. He has also written several books on amateur astronomy. Celestial Objects for Modern Telescopes specifies constellation pronunciations, most of them based on the English system, as explained on Covington's website Latin Pronunciation Demystified. Covington's pronunciations have served as a cross-check on the other authorities.

The editors of Sky & Telescope have served as a handy sample of the American amateur-astronomy community. Several pronunciations of constellation names were included because they were the most popular choice at S&T, even if they don't appear in any of the other sources.

Finally, it must be emphasized that these are suggestions, not rules. Nobody has the right to complain if you use one of the pronunciations listed here, but there are many equally legitimate ways to pronounce constellation names. For instance, many people rhyme all genitives ending in "i" and "ae" with "be" and "by," respectively. This is exactly backward from what's specified in the constellation names table above, but it's how these endings were pronounced in classical antiquity — and how they still are pronounced by many choral groups and by almost everyone outside the English-speaking world.

The bottom line is that if you're happy with the way you say something, and other people understand you, then there's no reason to change.