View source for Zeta Piscium

{{Starbox begin
 | name = Zeta Piscium
}}
{{Starbox image
| image = 
{{Location mark
 | image=Pisces IAU.svg | alt= | float=center | width=250
 | label= | position=right
 | mark=Red circle.svg | mark_width=10 | mark_link=ζ Psc
 | x=390 | y=475
}}
| caption=Location of ζ Piscium (circled)
}}
{{Starbox observe 2s
 | epoch = [[J2000.0]]
 | equinox = [[J2000.0]] ([[International Celestial Reference System|ICRS]])
 | constell = [[Pisces (constellation)|Pisces]]
 | component1 = ζ Psc A
 | ra1 = {{RA|01|13|45.17477}}<ref name=vanLeeuwen2007/>
 | dec1 = {{DEC|+07|34|31.2745}}<ref name=vanLeeuwen2007/>
 | appmag_v1 = 5.28<ref name=Eggleton2008/>
 | component2 = ζ Psc B
 | ra2 = {{RA|01|13|43.88735}}<ref name=vanLeeuwen2007/>
 | dec2 = {{DEC|+07|34|42.1765}}<ref name=vanLeeuwen2007/>
 | appmag_v2 = 6.43<ref name=Eggleton2008/>
}}
{{Starbox character
 | class = {{nowrap|A7IV + A7IV + F7V + G7V + ?}}<ref name=Eggleton2008/>
 | b-v = 
 | u-b = 
 | variable = 
}}
{{Starbox astrometry
 | component1 = ζ Psc A
 | radial_v = 
 | prop_mo_ra = +145.00<ref name=vanLeeuwen2007/>
 | prop_mo_dec = −55.69<ref name=vanLeeuwen2007/>
 | parallax = 18.76
 | p_error = 2.76
 | parallax_footnote = <ref name=vanLeeuwen2007/>
 | absmag_v = 1.97<ref name=Anderson2012/>
 | component2 = ζ Psc B
 | radial_v2 = 
 | prop_mo_ra2 = +181.78<ref name=vanLeeuwen2007/>
 | prop_mo_dec2 = −40.34<ref name=vanLeeuwen2007/>
 | absmag_v2 = 
}}
{{Starbox detail
 | source = <ref name=Zorec2012/>
 | component1 = ζ Psc A
 | mass = {{Val|2.07|0.13}}
 | radius = 
 | luminosity = 27.4
 | gravity = 
 | temperature = 7,345
 | metal_fe = 
 | rotational_velocity = 196
 | age_myr = 
 | component2 = ζ Psc B
 | metal2_fe = 0.18<ref name=Anderson2012/>
}}
{{Starbox catalog
 | names = Revati, {{odlist | B=ζ&nbsp;Psc | F=86&nbsp;Piscium }}
 | component1 = ζ Psc A
 | names1     = {{odlist | BD=+06° 174 | FK5=1033 | HD=7344 | HIP=5737 | HR=361 | SAO=109739 | WDS=J01137+0735A }}<ref name=SIMBAD1/>
 | component2 = ζ Psc B
 | names2     = {{odlist | BD=+06° 175 | HD=7345 | HIP=5743 | HR=362 | SAO=109740 | WDS=J01137+0735BC }}<ref name=SIMBAD2/>
}}
{{Starbox reference
 | Simbad = zet+Psc
}}
{{Starbox end}}
'''Zeta Piscium''' ('''ζ Piscium''', abbreviated '''Zet Psc''', '''ζ Psc''') is a quintuple<ref name=Eggleton2008/> [[star system]] in the [[zodiac]] [[constellation]] of [[Pisces (constellation)|Pisces]]. Based upon [[stellar parallax|parallax]] measurements obtained during the [[Hipparcos]] mission, it is located roughly {{Convert|170|ly|pc|abbr=off|lk=on}} distant from the [[Sun]].<ref name=vanLeeuwen2007/>

The system is composed of a [[binary star]] (designated '''Zeta Piscium A''') and a [[triple star system]] ('''BC'''), the latter consisting of a [[binary star#Spectroscopic binaries|spectroscopic binary]] ('''B''') and a single star ('''C'''). A's two components are themselves designated '''Zeta Piscium Aa''' (also named '''Revati'''<ref name="IAU-LSN">{{cite web | url=https://www.iau.org/public/themes/naming_stars/ | title=Naming Stars |publisher=IAU.org |accessdate=16 December 2017}}</ref>) and '''Ab'''; B's two components as '''Ba''' and '''Bb'''.

Because Zeta Piscium is positioned near the [[ecliptic]], it is subject to [[lunar eclipse]]s.<ref name=Meyer1995/>

== Nomenclature ==

''ζ Piscium'' ([[Latinisation of names|Latinised]] to ''Zeta Piscium'') is the system's [[Bayer designation]]. The designations of the three constituents as ''Zeta Piscium A'', ''B'' and ''C'', and those of ''A's'' and ''B's'' components - ''Zeta Piscium Aa'', ''Ab'', ''Ba'' and ''Bb'' - derive from the convention used by the Washington Multiplicity Catalog (WMC) for [[Star system|multiple star system]]s, and adopted by the [[International Astronomical Union]] (IAU).<ref name="planetnaming">{{cite arXiv |title=On the naming convention used for multiple star systems and extrasolar planets |date=2010 |eprint=1012.0707 |class=astro-ph.SR |last1= Hessman |first1=F. V. |last2= Dhillon |first2=V. S. |last3= Winget |first3=D. E. |last4= Schreiber |first4=M. R. |last5= Horne |first5=K. |last6= Marsh |first6=T. R. |last7= Guenther |first7=E. |last8= Schwope |first8=A. |last9= Heber |first9=U. }}</ref>

The system bore the traditional name ''[[Revati (nakshatra)|Revathi]]'' in [[Indian astronomy|Hindu sidereal astronomy]] and ''[[Revati (nakshatra)|Revati]]'', one of the [[nakshatra]] or [[lunar mansion]] in [[Hindu astrology]]. In 2016, the IAU organized a [[IAU Working Group on Star Names|Working Group on Star Names]] (WGSN)<ref name="WGSN">{{cite web | url=https://www.iau.org/science/scientific_bodies/working_groups/280/ | title=IAU Working Group on Star Names (WGSN)|accessdate=22 May 2016}}</ref> to catalog and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire [[multiple star|multiple systems]].<ref name="TriRpt18">{{cite web | url=https://www.iau.org/static/science/scientific_bodies/working_groups/280/wg-starnames-triennial-report-2015-2018.pdf | page=5 | title=WG Triennial Report (2015-2018) - Star Names |accessdate=2018-07-14}}</ref> It approved the name ''Revati'' for the constituent Zeta Piscium A on 30 June 2017 and it is now so included in the List of IAU-approved Star Names.<ref name="IAU-LSN"/> Where a component letter is not explicitly listed, the WGSN says that the name should be understood to be attributed to the brightest component by visual brightness (component ''Aa'' in this case).<ref name="WGSN2">{{cite web | url=http://www.pas.rochester.edu/~emamajek/WGSN/WGSN_bulletin2.pdf | title=Bulletin of the IAU Working Group on Star Names, No. 2 |accessdate=12 October 2016}}</ref>

In [[Chinese language|Chinese]], {{lang|zh|外屏}} ({{lang|zh-Latn|Wài Píng}}), meaning ''[[Legs (Chinese constellation)|Outer Fence]]'', refers to an [[Asterism (astronomy)|asterism]] consisting of Zeta Piscium, [[Delta Piscium]], [[Epsilon Piscium]], [[Mu Piscium]], [[Nu Piscium]], [[Xi Piscium]] and [[Alpha Piscium]]. Consequently, Zeta Piscium itself is known as {{lang|zh|外屏三}} ({{lang|zh-Latn|Wài Píng sān}}, {{lang-en|the Third Star of Outer Fence}}.)<ref>{{zh icon}} [http://aeea.nmns.edu.tw/2006/0605/ap060519.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日]</ref>

== Properties ==

The primary, Zeta Piscium A, forms a pair of [[stellar classification#Class A|A-type]] [[subgiant]] stars, with an [[angular distance|angular separation]] of 0.15&nbsp;[[Minute and second of arc|arcseconds]] and [[apparent magnitude|visual magnitude]] 5.28.<ref name=Eggleton2008/>

The secondary, Zeta Piscium B, is a [[binary star#Spectroscopic binaries|spectroscopic binary]] with a [[orbital period|period]] of 9.075&nbsp;days and an [[orbital eccentricity|eccentricity]] of 0.04. Together, components Ba and Bb have a combined visual magnitude of 6.43 and lie at an angular separation of 22.9&nbsp;arcseconds from the primary. They are a [[stellar classification#Class F|F-type]] [[main sequence]] star and a [[Stellar classification#Class G|G-type]] main sequence star, respectively.

The tertiary and fifth component, Zeta Piscium C, is a magnitude 12.2 star at an angular separation 1.0&nbsp;arc seconds from component B.<ref name=Eggleton2008/>

==References==
{{reflist|refs=

<ref name=vanLeeuwen2007>{{citation
 | title=Validation of the new Hipparcos reduction
 | last1=van Leeuwen | first1=F.
 | journal=Astronomy and Astrophysics
 | volume=474 | issue=2 | pages=653–664 | date=2007
 | arxiv=0708.1752 | bibcode=2007A&A...474..653V
 | doi=10.1051/0004-6361:20078357 | postscript=. }}</ref>

<ref name=Anderson2012>{{citation
 | title=XHIP: An extended hipparcos compilation
 | last1=Anderson | first1=E. | last2=Francis | first2=Ch.
 | journal=Astronomy Letters
 | volume=38 | issue=5 | pages=331 | year=2012
 | bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015
 | arxiv=1108.4971 | postscript=. }}</ref>

<ref name=Meyer1995>{{citation
 | display-authors=1 | last1=Meyer | first1=C.
 | last2=Rabbia | first2=Y. | last3=Froeschle | first3=M.
 | last4=Helmer | first4=G. | last5=Amieux | first5=G.
 | title=Observations of lunar occultations at Observatoire de la Cote d'Azur
 | journal=Astronomy and Astrophysics Supplement
 | volume=110 | pages=107 | year=1995
 | bibcode=1995A&AS..110..107M
 | postscript=. }}</ref>

<ref name=Zorec2012>{{citation
 | last1=Zorec | first1=J. | last2=Royer | first2=F.
 | title=Rotational velocities of A-type stars. IV. Evolution of rotational velocities
 | journal=Astronomy & Astrophysics
 | volume=537 | page=A120 | date=January 2012
 | doi=10.1051/0004-6361/201117691 | bibcode=2012A&A...537A.120Z
 | arxiv=1201.2052 | postscript=. }}</ref>

<ref name=Eggleton2008>{{citation
 | last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
 | title=A catalogue of multiplicity among bright stellar systems
 | journal=[[Monthly Notices of the Royal Astronomical Society]]
 | volume=389 | issue=2 | pages=869–879 | date=September 2008
 | doi=10.1111/j.1365-2966.2008.13596.x | bibcode=2008MNRAS.389..869E
 | arxiv=0806.2878 | postscript=.}}</ref>

<ref name=SIMBAD1>{{cite simbad
 | title=zet Psc A | accessdate=2017-07-31 | postscript=. }}</ref>

<ref name=SIMBAD2>{{cite simbad
 | title=zet Psc B | accessdate=2017-07-31 | postscript=. }}</ref>

}}

{{Stars of Pisces|state=collapsed}}

[[Category:Pisces (constellation)]]
[[Category:Bayer objects|Piscium, Zeta]]
[[Category:A-type subgiants]]
[[Category:F-type main-sequence stars]]
[[Category:G-type main-sequence stars]]
[[Category:Durchmusterung objects]]
[[Category:Flamsteed objects|Piscium, 086]]
[[Category:Henry Draper Catalogue objects|007344/45]]
[[Category:Hipparcos objects|005737/43]]
[[Category:HR objects|0361/0362]]