View source for Capricornus

{{Short description|Zodiac constellation in the southern hemisphere}}
{{About|the ''astronomical'' constellation|the ''astrological'' sign|Capricorn (astrology)|"Capricornis", the genus of goat/antelope-like mammals|Serow}}
{{Infobox constellation
|name=Capricornus
|abbreviation=Cap
|genitive=Capricorni
|pronounce={{IPAc-en|ˌ|k|æ|p|r|ᵻ|ˈ|k|ɔːr|n|ə|s}}, genitive {{IPAc-en|ˌ|k|æ|p|r|ᵻ|ˈ|k|ɔːr|n|aɪ}} 
|symbolism=the Sea-[[Goat]]
|RA={{RA|20|06|46.4871}} to {{RA|21|59|04.8693}}<ref name=boundary>{{Cite journal |title=Capricornus, constellation boundary |journal=The Constellations |publisher=[[International Astronomical Union]] |url=https://www.iau.org/public/themes/constellations/#cap |access-date=14 February 2014 |archive-date=28 January 2023 |archive-url=https://web.archive.org/web/20230128105231/https://www.iau.org/public/themes/constellations/#cap |url-status=dead }}</ref>
|dec={{dec|-8.4043999}} to {{dec|-27.6914144}}<ref name=boundary/>
|family=[[Zodiac]]
|areatotal=414
|arearank=40th
|numbermainstars=9, 13, 23
|numberbfstars=49
|numberbrightstars=1
|numbernearbystars=3
|brighteststarname=[[Delta Capricorni|δ Cap]] (Deneb Algedi)
|starmagnitude=2.85
|neareststarname=[[LP 816-60]]<ref name=Kirkpatrick2024/>{{rp|84}}
|stardistancely=18.33
|stardistancepc=5.62
|numbermessierobjects=1
|meteorshowers=[[Alpha Capricornids]]<br/>[[Chi Capricornids]]<br/>[[Sigma Capricornids]]<br/>[[Tau Capricornids]]<br/>[[Capricornids-Sagittariids]]
|bordering=[[Aquarius (constellation)|Aquarius]]<br/>[[Aquila (constellation)|Aquila]]<br/>[[Sagittarius (constellation)|Sagittarius]]<br/>[[Microscopium]]<br/>[[Piscis Austrinus]]
|latmax=[[62nd parallel north|62]]
|latmin=[[South Pole|90]]
|month=September
|notes=}}

'''Capricornus''' is one of the [[constellation]]s of the [[zodiac]]. Its name is [[Latin]] for "horned [[goat]]" or "goat [[Horn (anatomy)|horn]]" or "having horns like a goat's", and it is commonly represented in the form of a [[sea goat]]: a mythical creature that is half goat, half [[fish]]. 

Capricornus is one of the [[88 modern constellations]], and was also one of the 48&nbsp;constellations listed by the 2nd&nbsp;century astronomer [[Ptolemy|Claudius Ptolemy]]. Its traditional astrological symbol is [[Image:Capricornus symbol (fixed width).svg|20px]] (♑︎). Under its modern boundaries it is bordered by [[Aquila (constellation)|Aquila]], [[Sagittarius (constellation)|Sagittarius]], [[Microscopium]], [[Piscis Austrinus]], and [[Aquarius (constellation)|Aquarius]]. The constellation is located in an area of sky called the [[Sea (astronomy)|Sea]] or the Water, consisting of many water-related constellations such as Aquarius, [[Pisces (constellation)|Pisces]] and [[Eridanus (constellation)|Eridanus]]. It is the smallest constellation in the zodiac.

==Notable features==
[[Image:CapricornusCC.jpg|thumb|left|The constellation Capricornus as it can be seen with the naked eye<ref>{{cite web |url=http://www.allthesky.com/constellations/capricornus.html |title=Capricornus, the Goat |series=Constellations – Digital Images of the Sky |publisher=Allthesky.com |access-date=2012-05-16}}</ref>]]

===Stars===
{{See also|List of stars in Capricornus}}
Capricornus is a faint constellation, with only one star above magnitude&nbsp;3; its [[Bayer designation|alpha star]] has a magnitude of only 3.6.

The brightest star in Capricornus is [[Delta Capricorni|δ&nbsp;Capricorni]], also called Deneb Algedi, with a magnitude of 2.9, located 39&nbsp;light-years from Earth. Like several other stars such as [[Denebola]] and [[Deneb]], it is named from the Arabic word for "tail" (''deneb'') and “young goat / kid” (al-gedi), meaning "the tail of the goat". Deneb Algedi is a [[Beta Lyrae variable]] star (a type of [[eclipsing binary]]). It ranges by about 0.2&nbsp;magnitudes with a period of 24.5&nbsp;hours.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

The other bright stars in Capricornus range in magnitude from 3.1 to 5.1. [[Alpha Capricorni|α&nbsp;Capricorni]] is a multiple star. The primary ([[Alpha2 Capricorni|α<sup>2</sup>&nbsp;Cap]]), 109&nbsp;light-years from Earth, is a yellow-hued giant star of magnitude&nbsp;3.6; the secondary ([[Alpha1 Capricorni|α<sup>1</sup>&nbsp;Cap]]), 690&nbsp;light-years from Earth, is a yellow-hued supergiant star of magnitude&nbsp;4.3. The two stars are distinguishable by the naked eye, and both are themselves multiple stars. α<sup>1</sup>&nbsp;Capricorni is accompanied by a star of magnitude&nbsp;9.2; α<sup>2</sup>&nbsp;Capricorni is accompanied by a star of magnitude 11.0; this faint star is itself a binary star with two components of magnitude&nbsp;11. Also called Algedi or Giedi, the traditional names of α&nbsp;Capricorni come from the Arabic word for "the kid", which references the constellation's mythology.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

[[Beta Capricorni|β Capricorni]] is a [[double star]] also known as Dabih. It is a yellow-hued giant star of magnitude&nbsp;3.1, 340&nbsp;light-years from Earth. The secondary is a blue-white hued star of magnitude 6.1. The two stars are distinguishable in binoculars. β&nbsp;Capricorni's traditional name comes from the Arabic phrase for "the lucky stars of the slaughterer," a reference to ritual sacrifices performed by ancient Arabs at the [[heliacal rising]] of Capricornus.<ref>{{cite book |first=Mark R. III |last=Chartrand |year=1983 |title=Skyguide: A Field Guide for Amateur Astronomers |page=126 |publisher=Golden Press |isbn=0-307-13667-1}}</ref> Another star visible to the naked eye is [[Gamma Capricorni|γ&nbsp;Capricorni]], sometimes called Nashira ("bringing good tidings"); it is a white-hued giant star of magnitude&nbsp;3.7, 139&nbsp;light-years from Earth. [[Pi Capricorni|π Capricorni]] is a double star with a blue-white hued primary of magnitude&nbsp;5.1 and a white-hued secondary of magnitude&nbsp;8.3. It is 670&nbsp;light-years from Earth and the components are distinguishable in a small telescope.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

===Deep-sky objects===
[[File:Messier_30_Hubble_WikiSky.jpg|thumb|right|The globular cluster Messier 30 imaged by the [[Hubble Space Telescope]]]]
Several galaxies and star clusters are contained within Capricornus. [[Messier 30]] is a globular cluster located 1&nbsp;degree south of the galaxy group that contains [[NGC 7103]]. The constellation also harbors the wide spiral galaxy [[NGC 6907]].

Messier 30 (NGC 7099) is a centrally-condensed globular cluster of magnitude 7.5&nbsp;. At a distance of 30,000&nbsp;light-years, it has chains of stars extending to the north that are resolvable in small amateur telescopes.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

One [[galaxy group]] located in Capricornus is [[HCG 87]], a group of at least three galaxies located 400&nbsp;million [[light-years]] from Earth ([[redshift]] 0.0296). It contains a large [[elliptical galaxy]], a face-on [[spiral galaxy]], and an edge-on spiral galaxy. The face-on spiral galaxy is experiencing abnormally high rates of [[star formation]], indicating that it is [[interacting galaxy|interacting]] with one or both members of the group. Furthermore, the large elliptical galaxy and the edge-on spiral galaxy, both of which have [[active galactic nucleus|active nuclei]], are connected by a stream of stars and dust, indicating that they too are interacting. Astronomers predict that the three galaxies may [[galaxy merger|merge]] millions of years in the future to form a giant elliptical galaxy.<ref name="objects">{{Harvnb|Wilkins|Dunn|2006}}</ref>

==History ==
The constellation was first attested in depictions on a cylinder-seal from around the 21st&nbsp;century&nbsp;BCE,<ref name=Espak2006>{{cite thesis |type=Masters |title=Master's Thesis |first=Peeter |last=Espak |year=2006 |page=104 |url=http://dspace.utlib.ee/dspace/bitstream/10062/958/5/espakpeeter.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://dspace.utlib.ee/dspace/bitstream/10062/958/5/espakpeeter.pdf |archive-date=2022-10-09 |url-status=live}}</ref> it was explicitly recorded in the [[Babylonian star catalogues]] before 1000&nbsp;BCE. In the [[Early Bronze Age]] the [[winter solstice]] occurred in the constellation, but due to the [[precession of the equinoxes]], the [[December solstice]] now takes place in the constellation [[Sagittarius (constellation)|Sagittarius]].<ref name=Rogers1998>{{cite journal |first=John H. |last=Rogers |title=Origins of the ancient constellations: I.&nbsp;The Mesopotamian traditions |journal=Journal of the British Astronomical Association |volume=108 |year=1998 |pages=9–28 |bibcode=1998JBAA..108....9R}}</ref> The Sun is now in the constellation Capricorn (as distinct from the astrological sign) from late January through mid-February.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

Although the solstice during the northern hemisphere's winter no longer takes place while the sun is in the ''constellation'' Capricornus, as it did until 130&nbsp;BCE, the [[Capricorn (astrology)|''astrological sign'' called Capricorn]] is still used to denote the position of the solstice, and the latitude of the sun's most southerly position continues to be called the ''[[Tropic of Capricorn]]'', a term which also applies to the line on the Earth at which the sun is directly overhead at local noon on the day of the December solstice.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

The planet [[Neptune]] was discovered by German astronomer [[Johann Gottfried Galle|Johann Galle]], near Deneb Algedi (δ&nbsp;Capricorni) on 23&nbsp;September 1846, as Capricornus can be seen best from Europe at 4:00{{sc|am}} in September (although, by modern constellation boundaries established in the early 20th&nbsp;century&nbsp;CE, Neptune lay within the confines of Aquarius at the time of its discovery).

==Mythology==
Despite its faintness, the constellation Capricornus has one of the oldest mythological associations, having been consistently represented as a [[mythological hybrid|hybrid]] of a goat and a fish since the [[Middle Bronze Age]], when the [[Babylonian star catalogues|Babylonians]] used {{lang|sux-Latn|<sup>MUL</sup>SUḪUR.MAŠ}} "The Goat-Fish" as a symbol of their god [[Ea (god)|Ea]].<ref name=Rogers1998/><ref name=Espak2006/>

In [[Greek mythology]], the constellation is sometimes identified as [[Amalthea (mythology)|Amalthea]], the goat that suckled the infant [[Zeus]] after his mother, [[Rhea (mythology)|Rhea]], saved him from being devoured by his father, [[Cronus|Cronos]]. Amalthea's broken horn was transformed into the [[cornucopia]] or "horn of plenty".<ref name="Reference and Allusion">{{cite book |last1=Delahunty |first1=Andrew |last2=Dignen |first2=Sheila |title=Oxford Dictionary of Reference and Allusion |date=2012 |publisher=[[Oxford University Press]] |isbn=978-0-19-956746-1 |page=91 |edition=3rd |url=https://books.google.com/books?id=hX6rCuCLI2MC&pg=PA91 |via=Google Books}}</ref>

Capricornus is also sometimes identified as [[Pan (god)|Pan]], the god with a goat's horns and legs, who saved himself from the monster [[Typhon]] by giving himself a fish's tail and diving into a river.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

==Visualizations==
[[File:Sidney Hall - Urania's Mirror - Capricornus.jpg|thumb|right|Capricornus as a sea-goat from ''[[Urania's Mirror]]'' (1825)]]
Capricornus's brighter stars are found on a triangle whose vertices are [[Alpha Capricorni|α<sup>2</sup> Capricorni]] (Giedi), [[Delta Capricorni|δ Capricorni]] (Deneb Algiedi), and [[Omega Capricorni|ω Capricorni]]. Ptolemy's method of connecting the stars of Capricornus has been influential.<ref>{{cite web|url=http://jebrown.us/SolarAlmanac/private/Articles/Constellations/Capricornus.html#Ptolemy |title=Capricornus |publisher=Jebrown.us |access-date=2012-05-16}}</ref> Capricornus is usually drawn as a goat with the tail of a fish.{{sfn|Ridpath|Tirion|2001|pp=102–103}}

[[Image:Capricornus constellation map visualization.PNG|thumb|right|Diagram of H.A. Rey's alternative way to connect the stars of the Capricornus constellation]]
[[H. A. Rey]] has suggested an alternative visualization, which graphically shows a [[goat]].<ref>{{Harvnb|Rey|1997}}</ref> The goat's head is formed by the triangle of stars [[Iota Capricorni|ι Cap]], [[Theta Capricorni|θ Cap]], and [[Zeta Capricorni|ζ Cap]]. The goat's horn sticks out with stars [[Gamma Capricorni|γ Cap]] and δ Cap. Star δ Cap, at the tip of the horn, is of the third magnitude. The goat's tail consists of stars [[Beta Capricorni|β Cap]] and α<sup>2</sup> Cap: star β Cap being of the third magnitude. The goat's hind foot consists of stars [[Psi Capricorni|ψ Cap]] and ω Cap. Both of these stars are of the fourth magnitude.

==Equivalents==
In [[Chinese astronomy]], constellation Capricornus lies in ''[[Black Tortoise|The Black Tortoise of the North]]'' ({{Lang-zh|c=北方玄武|p=Běi Fāng Xuán Wǔ|labels=no}}).

The [[Nakh peoples]] called this constellation Roofing Towers ({{langx|ce|Neģara Bjovnaš}}).

In the [[Society Islands]], the figure of Capricornus was called ''Rua-o-Mere'', "Cavern of parental yearnings".{{sfn|Makemson|1941|p=251}}

In [[Indian astronomy]] and [[Indian astrology]], it is called [[Makara]], the crocodile.

==See also==
*[[Capricornus in Chinese astronomy]]
*[[Hippocampus (mythology)]], the mythological sea horse
*[[IC 1337]], galaxy

==Citations==
;Citations
{{Reflist|refs=

<ref name=Kirkpatrick2024>{{cite journal |last1=Kirkpatrick |first1=J. Davy |last2=Marocco |first2=Federico |display-authors=etal |date=April 2024 |title=The Initial Mass Function Based on the Full-sky 20 pc Census of ~3600 Stars and Brown Dwarfs |journal=[[The Astrophysical Journal Supplement Series]] |volume=271 |issue=2 |pages=55 |doi=10.3847/1538-4365/ad24e2 |doi-access=free |arxiv=2312.03639 |bibcode=2024ApJS..271...55K}}</ref>

}}
;References
* {{cite book
  | last = Makemson
  | first = Maud Worcester
  | year = 1941
  | publisher = [[Yale University Press]]
  | title = The Morning Star Rises: an account of Polynesian astronomy	
  | bibcode = 1941msra.book.....M
 }}
* {{citation |last=Rey |first=H. A. |title=The Stars — A New Way To See Them |year=1997 |publisher=Houghton Mifflin |isbn=0-395-24830-2 |url-access=registration |url=https://archive.org/details/stars00hare }}
* {{citation |first1 = Ian |last1 = Ridpath |first2 = Wil |last2 = Tirion |title = Stars and Planets Guide |publisher = Princeton University Press |year = 2001 |isbn = 0-691-08913-2}}
* {{citation |first1 = Ian |last1 = Ridpath |first2 = Wil |last2 = Tirion |title = Stars and Planets Guide |publisher = Princeton University Press |year = 2007 |isbn = 978-0-691-13556-4}}
* {{citation |title = 300 Astronomical Objects: A Visual Reference to the Universe |last1=Wilkins |first1=Jamie |last2=Dunn |first2 = Robert |publisher = Firefly Books |year = 2006 |edition = 1st |isbn = 978-1-55407-175-3}}

==External links==
{{Commons}}
*[http://www.allthesky.com/constellations/capricornus/ The Deep Photographic Guide to the Constellations: Capricornus]
*[http://www.ianridpath.com/startales/capricornus.html Ian Ridpath's Star Tales – Capricornus]
*[https://iconographic.warburg.sas.ac.uk/category/vpc-taxonomy-017068 Warburg Institute Iconographic Database (medieval and early modern images of Capricornus)]

{{Stars of Capricornus}}
{{Constellations}}
{{Zodiac}}
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{{DEFAULTSORT:Capricornus}}
[[Category:Capricornus| ]]
[[Category:Constellations]]
[[Category:Southern constellations]]
[[Category:Constellations listed by Ptolemy]]