Editing IAU designated constellations (section)

{{Short description|Constellations recognized by the International Astronomical Union}}
{{Use dmy dates|date=March 2024}}

[[File:Constellations, equirectangular plot.svg|thumb|500px|right|IAU designated constellations in equirectangular projection (epoch [[Epoch (astronomy)#Besselian years|B1875.0]])]]

In contemporary [[astronomy]], 88 [[constellations]] are recognized by the [[International Astronomical Union]] (IAU).<ref name="international astronomical union">{{cite web |url=https://www.iau.org/public/themes/constellations/ |title=The Constellations |publisher=[[International Astronomical Union]] |access-date=26 July 2019 |archive-date=16 December 2020 |archive-url=https://web.archive.org/web/20201216152749/https://www.iau.org/public/themes/constellations/ |url-status=live }}</ref> 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.<ref name="international astronomical union-1930">{{cite book|author1=Eugène Delporte|author2=International Astronomical Union|title=Délimitation scientifique des constellations|url=https://books.google.com/books?id=v3XvAAAAMAAJ|year=1930|publisher=At the University press}}</ref>

The ancient [[Mesopotamian]]s and later the [[Greek astronomy|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 Navis|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.<ref name="international astronomical union" /><ref name="international astronomical union-1930" /> When astronomers say that an object lies in a particular constellation, they mean that it is positioned within these specified boundaries.