Editing Constellation (section)

==Early modern astronomy==
Historically, the origins of the constellations of the northern and southern skies are distinctly different. Most northern constellations date to antiquity, with names based mostly on Classical Greek legends.<ref name="Norton14th">{{cite book |last=Norton |first=Arthur P. |title=Norton's Star Atlas |title-link=Norton's Star Atlas |year=1959 |page=1}}</ref> Evidence of these constellations has survived in the form of [[star charts]], whose oldest representation appears on the statue known as the [[Farnese Atlas]], based perhaps on the star catalogue of the Greek astronomer [[Hipparchus]].<ref name="Bradley2005">{{cite journal
|last=Schaefer | first=Bradley E.
|title=The epoch of the constellations on the Farnese Atlas and their origin in Hipparchus's lost catalogue
|journal=Journal for the History of Astronomy
|volume=36/2 | issue=123 | pages=167–19
|date=May 2005 | bibcode=2005JHA....36..167S |doi=10.1177/002182860503600202 | s2cid=15431718
|url=http://www.phys.lsu.edu/farnese/JHAFarneseProofs.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.phys.lsu.edu/farnese/JHAFarneseProofs.pdf |archive-date=2022-10-09 |url-status=live }}</ref> Southern constellations are more modern inventions, sometimes as substitutes for ancient constellations (e.g. [[Argo Navis]]). Some southern constellations had long names that were shortened to more usable forms; e.g. Musca Australis became simply Musca.<ref name="Norton14th" />

Some of the early constellations were never universally adopted. Stars were often grouped into constellations differently by different observers, and the arbitrary constellation boundaries often led to confusion as to which constellation a celestial object belonged. Before astronomers delineated precise boundaries (starting in the 19th century), constellations generally appeared as ill-defined regions of the sky.<ref name="Norton2nd">{{cite book |last=Norton |first=Arthur P. |title=Norton's Star Atlas |title-link=Norton's Star Atlas |year=1919 |page=1}}</ref> Today they now follow officially accepted designated lines of [[right ascension]] and [[declination]] based on those defined by [[Benjamin Apthorp Gould|Benjamin Gould]] in [[Equinox (celestial coordinates)|Equinox]] B1875.0 in his star catalogue ''Uranometria Argentina''.<ref>{{cite web
|url=http://www.optcorp.com/edu/articleDetailEDU.aspx?aid=2195
|title=Astronomical Epoch
|access-date=16 July 2010
|url-status=dead
|archive-url=https://web.archive.org/web/20110724193348/http://www.optcorp.com/edu/articleDetailEDU.aspx?aid=2195
|archive-date=24 July 2011 }}</ref>

The 1603 star atlas "[[Uranometria]]" of [[Johann Bayer]] assigned stars to individual constellations and formalized the division by assigning a series of Greek and Latin letters to the stars within each constellation. These are known today as [[Bayer designation]]s.<ref name="Swerdlow1986">{{cite journal |last=Swerdlow |first=N. M. |date=August 1986 |title=A Star Catalogue Used by Johannes Bayer |journal=Journal for the History of Astronomy |volume=17 |issue=5 |pages=189–97 |bibcode=1986JHA....17..189S |doi=10.1177/002182868601700304 |s2cid=118829690}}</ref> Subsequent star atlases led to the development of today's accepted modern constellations.

===Origin of the southern constellations===
{{See also|Uranometria|Harmonia Macrocosmica|Former constellations}}
[[Image:Southern Celestial Map of Mestre João Faras.gif|thumb|right|Sketch of the southern celestial sky by Portuguese astronomer [[João Faras]] (1 May 1500)]]
[[File:Planisphæri cœleste.jpg|thumb|A [[celestial chart|celestial map]] from the [[Golden Age of Netherlandish cartography]], by the Dutch cartographer [[Frederik de Wit]]]]

The southern sky, below about −65° [[declination]], was only partially catalogued by ancient Babylonians, Egyptians, Greeks, Chinese, and Persian astronomers of the north. The knowledge that northern and southern star patterns differed goes back to Classical writers, who describe, for example, the [[Exploration of Africa|African circumnavigation]] expedition commissioned by Egyptian Pharaoh Necho II in c.&nbsp;600&nbsp;BC and those of [[Hanno the Navigator]] in c.&nbsp;500&nbsp;BC.

The history of southern constellations is not straightforward. Different groupings and different names were proposed by various observers, some reflecting national traditions or designed to promote various sponsors. Southern constellations were important from the 14th to 16th centuries, when sailors used the stars for [[celestial navigation]]. Italian explorers who recorded new southern constellations include [[Andrea Corsali]], [[Antonio Pigafetta]], and [[Amerigo Vespucci]].<ref name="Allen1899" />

Many of the 88 IAU-recognized constellations in this region first appeared on celestial globes developed in the late 16th century by [[Petrus Plancius]], based mainly on observations of the Dutch navigators [[Pieter Dirkszoon Keyser]]<ref>{{cite journal |last=Hogg |first=Helen Sawyer |author-link=Helen Sawyer Hogg |date=1951 |title=Out of Old Books (Pieter Dircksz Keijser, Delineator of the Southern Constellations) |journal=Journal of the Royal Astronomical Society of Canada |volume=45 |page=215 |bibcode=1951JRASC..45..215S}}</ref> and [[Frederick de Houtman]].<ref>Knobel, E. B. (1917). ''On Frederick de Houtman's Catalogue of Southern Stars, and the Origin of the Southern Constellations''. (''[[Monthly Notices of the Royal Astronomical Society]]'', Vol. 77, pp.&nbsp; 414–32)</ref><ref>[[Elly Dekker|Dekker, Elly]] (1987). ''Early Explorations of the Southern Celestial Sky''. (''Annals of Science'' 44, pp.&nbsp; 439–70)</ref><ref>[[Elly Dekker|Dekker, Elly]] (1987). ''On the Dispersal of Knowledge of the Southern Celestial Sky''. (''Der Globusfreund'', 35–37, pp.&nbsp; 211–30)</ref><ref>Verbunt, Frank; van Gent, Robert H. (2011). ''Early Star Catalogues of the Southern Sky: De Houtman, Kepler (Second and Third Classes), and Halley''. (''Astronomy & Astrophysics'' 530)</ref> These became widely known through [[Johann Bayer]]'s [[star atlas]] ''[[Uranometria]]'' of 1603.<ref>{{cite web|work = Star Tales
|url=http://www.ianridpath.com/startales/bayer-southern.html
|title=Johann Bayer's southern star chart
|author=Ian Ridpath}}</ref> [[:Category:Constellations listed by Lacaille|Fourteen]] more were created in 1763 by the French astronomer [[Nicolas Louis de Lacaille]], who also split the ancient constellation Argo Navis into three; these new figures appeared in his star catalogue, published in 1756.<ref>{{cite web |work = Star Tales
|url=http://www.ianridpath.com/startales/lacaille.html
|title=Lacaille's southern planisphere of 1756
|author=Ian Ridpath}}</ref>

Several modern proposals have not survived. The French astronomers [[Pierre Lemonnier (physicist)|Pierre Lemonnier]] and [[Joseph Lalande]], for example, proposed constellations that were once popular but have since been dropped. The northern constellation [[Quadrans Muralis]] survived into the 19th century (when its name was attached to the [[Quadrantid]] meteor shower), but is now divided between [[Boötes]] and [[Draco (constellation)|Draco]].

===88 modern constellations===
{{Main|IAU designated constellations}}

A list of 88 constellations was produced for the IAU in 1922.<ref name="auto" /> It is roughly based on the traditional Greek constellations listed by Ptolemy in his ''Almagest'' in the 2nd century and [[Aratus]]' work ''Phenomena'', with early modern modifications and additions (most importantly introducing constellations covering the parts of the southern sky unknown to Ptolemy) by Petrus Plancius (1592, 1597/98 and 1613), [[Johannes Hevelius]] (1690) and Nicolas Louis de Lacaille (1763),<ref name="iau-const">{{cite web |title=The Constellations |url=https://www.iau.org/public/themes/constellations/ |publisher=IAU – [[International Astronomical Union]] |access-date=29 August 2015}}</ref><ref>{{cite web |url=http://www.ianridpath.com/constellations1.html |title=Constellation names, abbreviations and sizes |author=Ian Ridpath |access-date= 30 August 2015}}</ref><ref>{{cite web |url=http://www.ianridpath.com/startales/almagest.html |title=Star Tales – The Almagest |author=Ian Ridpath |access-date=30 August 2015}}</ref> who introduced fourteen new constellations.<ref>{{cite web |url= http://www.ianridpath.com/startales/startales1d.html#lacaille |title=Nicolas Louis de Lacaille at the Cape|author=Ian Ridpath |access-date=4 July 2022}}</ref> Lacaille studied the stars of the southern hemisphere from 1751 until 1752 from the [[Cape of Good Hope]], when he was said to have observed more than 10,000 stars using a [[refracting telescope]] with an aperture of {{convert |0.5|in|mm}}.

In 1922, [[Henry Norris Russell]] produced a list of 88 constellations with three-letter abbreviations for them.<ref>{{cite web| url = http://www.ianridpath.com/iaulist1.html| title = The original names and abbreviations for constellations from 1922| access-date = 31 January 2010}}</ref> However, these constellations did not have clear borders between them. In 1928, the IAU formally accepted the 88 modern constellations, with contiguous boundaries<ref>{{cite web| url = http://www.ianridpath.com/boundaries.html| title = Constellation boundaries. | access-date = 24 May 2011}}</ref> along vertical and horizontal lines of [[right ascension]] and [[declination]] developed by [[Eugène Joseph Delporte|Eugene Delporte]] that, together, cover the entire celestial sphere;<ref name="auto"/><ref name="Lachièze-ReyLuminet2001">{{cite book|author1=Marc Lachièze-Rey|author2=Jean-Pierre Luminet|author3=Bibliothèque Nationale de France. Paris|title=Celestial Treasury: From the Music of the Spheres to the Conquest of Space|url=https://books.google.com/books?id=0ZFXiNn62ZEC&pg=PA80|date=2001|publisher=Cambridge University Press|isbn=978-0-521-80040-2|page=80}}</ref> this list was finally published in 1930.<ref name="IAU1928"/> Where possible, these modern constellations usually share the names of their Graeco-Roman predecessors, such as Orion, Leo, or Scorpius. The aim of this system is area-mapping, i.e. the division of the celestial sphere into contiguous fields.<ref name="iau-const" /> Out of the 88 modern constellations, 36 lie predominantly in the northern sky, and the other 52 predominantly in the southern.

{{scalable image|Hipparcos Catalogue equirectangular plot.svg|650px|{{center|Equirectangular plot of declination vs right ascension of stars brighter than apparent magnitude 5 on the [[Hipparcos Catalogue]], coded by spectral type and apparent magnitude, relative to the modern constellations and the ecliptic}}}}

The boundaries developed by Delporte used data that originated back to epoch [[epoch (astronomy)#Besselian years|B1875.0]], which was when [[Benjamin A. Gould]] first made his proposal to designate boundaries for the celestial sphere,<ref>{{cite web|work = Star Tales
|url= http://www.ianridpath.com/startales/gould.html
|title=Benjamin Apthorp Gould and the ''Uranometria Argentina''
|author=Ian Ridpath}}</ref> a suggestion on which Delporte based his work. The consequence of this early date is that because of the [[precession (astronomy)|precession]] of the [[equinox]]es, the borders on a modern star map, such as epoch [[J2000]], are already somewhat skewed and no longer perfectly vertical or horizontal.<ref>A.C. Davenhall & S.K. Leggett, [http://cdsarc.u-strasbg.fr/ftp/cats/VI/49/constell.pdf "A Catalogue of Constellation Boundary Data"], (Centre de Donneés astronomiques de Strasbourg, February 1990).</ref> This effect will increase over the years and centuries to come.

===Symbols===
{{main|Astronomical symbol#Symbols for zodiac and other constellations}}
The constellations have no official symbols, though those of the ecliptic may take the signs of the zodiac.<ref>For example, in the ''Nautical Almanac and Astronomical Ephemeris for the year 1833'' (Board of Admiralty, London)</ref> Symbols for the other modern constellations, as well as older ones that still occur in modern nomenclature, have occasionally been published.<ref>Peter Grego (2012) ''The Star Book: Stargazing Throughout the Seasons in the Northern Hemisphere''. F+W Media.</ref><ref name=constellations>{{cite web |url=https://www.unicode.org/L2/L2024/24235-constellation-symbols.pdf |title=Preliminary presentation of constellation symbols |last=Miller |first=Kirk |date=18 October 2024 |website=unicode.org |publisher=The Unicode Consortium |access-date=22 October 2024 |quote=}}</ref>