IAU designated constellations

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 ==

The 88 constellations depict 42 animals, 29 inanimate objects, and 17 humans or mythological characters. Abbreviations 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). 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 The four-letter abbreviations were repealed in 1955 and are now obsolete, but were included in the NASA Dictionary of Technical Terms for Aerospace Use (NASA SP-7) published in 1965. These are labeled "NASA" in the table below and are included here for reference only. List 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. } || Aps || Apus || Apodis || 1598, Plancius, Keyser, de Houtman || bird-of-paradise || α Apodis == Asterisms ==

Various other unofficial patterns exist alongside the constellations. These are known as "asterisms". Some are part of one larger constellation while others consists of stars in two adjoining constellations. Examples include the Big Dipper/Plough in Ursa Major; the Teapot in Sagittarius; the Square of Pegasus in Pegasus and Andromeda; and the False Cross in Carina and Vela. == See also ==