View source for Astronomy:Xi Columbae

{{Short description|Star in the constellation Columba}}
{{Starbox begin
 | name = Xi Columbae
}}
{{Starbox observe
 | epoch = [[Astronomy:J2000.0|J2000.0]]
 | equinox = [[Astronomy:J2000.0|J2000.0]] ([[Astronomy:International Celestial Reference System|ICRS]])
 | constell = [[Astronomy:Columba (constellation)|Columba]]
 | ra = {{RA|05|55|29.91038}}<ref name=GaiaDR2/>
 | dec = {{DEC|−37|07|14.3232}}<ref name=GaiaDR2/>
 | appmag_v = 4.97<ref name=Luck2015/>
}}
{{Starbox character
 | class = {{Nowrap|K1 III CNII}}<ref name=houk1979/>
 | b-v = +1.096<ref name=Luck2015/>
 | u-b = 
 | r-i = 
 | variable = 
}}
{{Starbox astrometry
 | radial_v = +59.5<ref name=Wilson1953/>
 | prop_mo_ra = +38.020<ref name=GaiaDR2/>
 | prop_mo_dec = −23.491<ref name=GaiaDR2/>
 | parallax = 10.0920
 | p_error = 0.1408
 | parallax_footnote = <ref name=GaiaDR2/>
 | absmag_v = −0.05<ref name=Setaiwan2004/>
}}
{{Starbox orbit
 | reference = <ref name=Setaiwan2004/>
 | period_unitless = 1420.6&nbsp;d
 | axis = <!--Semimajor axis (in arcseconds)-->
 | axis_unitless = 3.60&nbsp;AU
 | eccentricity = 0.39
 | inclination = <!--Inclination (in degrees)-->
 | node = <!--Longitude of node (in degrees)-->
 | periastron = <!--Periastron epoch-->
 | periarg = <!--Argument of periastron (in degrees), secondary -->
 | periarg_primary = <!--Argument of periastron (in degrees), primary -->
 | k1 = 5.68
 | k2 = <!-- Velocity semi-amplitude (secondary in SB2), in km/s -->
}}
{{Starbox detail
 | source = 
 | mass = 
 | radius = {{Val|16.23|0.14|2.27}}<ref name=GaiaDR2/>
 | luminosity = {{Val|120|2}}<ref name=GaiaDR2/>
 | temperature = {{Val|4743|372|20|fmt=commas}}<ref name=GaiaDR2/>
 | gravity = 2.26<ref name=Luck2015/>
 | metal_fe = +0.29<ref name=Luck2015/>
 | rotational_velocity = 2.6<ref name=Setaiwan2004/>
 | age_gyr = 
}}
{{Starbox catalog
 | names = {{odlist | B=ξ&nbsp;Col | CD=−37°2487 | HD=40176 | HIP=28010 | HR=2087 | SAO=196316 }}<ref name=SIMBAD/>
}}
{{Starbox reference
 | Simbad = ksi+Col
}}
{{starbox end}}

'''Xi Columbae''' is a [[Astronomy:Binary star|binary star]]<ref name=Setaiwan2004/> system in the southern [[Astronomy:Constellation|constellation]] of [[Astronomy:Columba (constellation)|Columba]]. With an [[Astronomy:Apparent visual magnitude|apparent visual magnitude]] of 4.97,<ref name=Luck2015/> it is faintly visible to the naked eye. Based upon an annual [[Astronomy:Stellar parallax|parallax shift]] of {{Val|10.1|ul=mas}},<ref name=GaiaDR2/> it is located around 323&nbsp;[[Light year|light year]]s from the [[Astronomy:Sun|Sun]]. The system is a member of the [[Astronomy:HR 1614|HR 1614]] supergroup,<ref name=Eggen1997/> and is drifting further away with a [[Astronomy:Radial velocity|radial velocity]] of +59.5&nbsp;km/s,<ref name=Wilson1953/>

This is an [[Astronomy:Astrometric binary|astrometric binary]]<ref name=Eggleton2008/> with an [[Astronomy:Orbital period|orbital period]] of 1,420.6&nbsp;days and an [[Astronomy:Orbital eccentricity|eccentricity]] of 0.39.<ref name=Setaiwan2004/> The primary is an [[Astronomy:Stellar evolution|evolved]] [[Astronomy:K-type star|K-type]] [[Astronomy:Giant star|giant star]] with a [[Astronomy:Stellar classification|stellar classification]] of {{Nowrap|K1 III CNII}},<ref name=houk1979/>  showing an overabundance of [[Chemistry:Cyanide|CN]] in its spectrum. The star has expanded to 16 times the radius of the Sun and is radiating 120 times the Sun's luminosity from its swollen [[Astronomy:Photosphere|photosphere]] at an [[Astronomy:Effective temperature|effective temperature]] of 4,743&nbsp;K.<ref name=GaiaDR2/> The companion has a mass of at least 59% that of the Sun.<ref name=Setaiwan2004/>

==References==
{{reflist|refs=

<ref name=GaiaDR2>{{cite DR2|2884366106030590080}}</ref>

<ref name=Eggen1997>{{citation
 | title=The Abundance of CN, Calcium and Heavy Elements in High Velocity Stars.
 | last1=Eggen | first1=Olin J.
 | journal=The Astronomical Journal | volume=114 | pages=825–836
 | date=August 1997 | postscript=.
 | doi=10.1086/118516 | bibcode=1997AJ....114..825E }}</ref>

<ref name=Setaiwan2004>{{citation
 | title=Precise radial velocity measurements of G and K giants. Multiple systems and variability trend along the Red Giant Branch
 | last1=Setiawan | first1=J. | last2=Pasquini | first2=L.
 | last3=da Silva | first3=L. | last4=Hatzes | first4=A. P.
 | last5=von der Lühe | first5=O. | last6=Girardi | first6=L.
 | last7=de Medeiros | first7=J. R. | last8=Guenther | first8=E.
 | journal=Astronomy and Astrophysics
 | volume=421 | pages=241–254 | date=July 2004
 | doi=10.1051/0004-6361:20041042-1 | bibcode=2004A&A...421..241S
 | display-authors=1 | postscript=. | doi-access=free }}</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 | s2cid=14878976 | postscript=. }}</ref>

<ref name=Luck2015>{{citation
 | title=Abundances in the Local Region. I. G and K Giants
 | last1=Luck | first1=R. Earle
 | journal=The Astronomical Journal
 | volume=150 | issue=3 | id=88 | pages=23 | date=September 2015
 | doi=10.1088/0004-6256/150/3/88 | bibcode=2015AJ....150...88L
 | arxiv=1507.01466 | s2cid=118505114 | postscript=. }}</ref>

<ref name=houk1979>{{citation
 | title=Michigan catalogue of two-dimensional spectral types for the HD stars
 | volume=3 | last1=Houk | first1=Nancy
 | location=Ann Arbor, Michigan | year=1979 
 | publisher=Dept. of Astronomy, University of Michigan
 | bibcode=1982mcts.book.....H | postscript=. }}</ref>

<ref name=Wilson1953>{{citation
 | last=Wilson | first=Ralph Elmer | year=1953
 | title=General Catalogue of Stellar Radial Velocities
 | journal=Carnegie Institute Washington D.C. Publication | publisher=Carnegie Institution of Washington | location=Washington
 | bibcode=1953GCRV..C......0W | postscript=. }}</ref>

<ref name=SIMBAD>{{citation
 | title=ksi Col -- Star
 | work=SIMBAD Astronomical Database
 | publisher=Centre de Données astronomiques de Strasbourg
 | url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=ksi+Col
 | access-date=2016-12-31 | postscript=. }}</ref>

}}

{{Stars of Columba|state=collapsed}}
<!-- Properties -->
{{DEFAULTSORT:Xi Columbae}}
[[Category:K-type giants]]
[[Category:Astrometric binaries]]
<!-- Identifiers -->
[[Category:Columba (constellation)]]
[[Category:Bayer objects|Columbae, Xi]]
[[Category:Durchmusterung objects]]
[[Category:Henry Draper Catalogue objects|040176]]
[[Category:Hipparcos objects|028010]]
[[Category:Bright Star Catalogue objects|02087]]

{{Sourceattribution|Xi Columbae}}