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{{Short description|Star in the constellation Centaurus}}
{{about|γ Centauri|HD 127233|Y Centauri|y Centauri|HD 120987}}
{{about-distinguish|γ Centauri|Y Centauri|HD 120987{{!}}y Centauri}}
{{Starbox begin
{{Starbox begin}}
⚫
| name=Gamma Centauri A/B
}}
{{Starbox image
{{Starbox image
| image =
| image =
{{Location mark
<div style="position: relative">[[File:Centaurus IAU.svg|280px|alt=Diagram showing star positions and boundaries of the Centauri constellation and its surroundings]]
| image=Centaurus IAU.svg
<div style="position: absolute; left: 145px; top: 117px">[[File:Cercle rouge 100%.svg|12px]]</div>
| float=center | width=240 | position=right
</div>
| mark=Red circle.svg | mark_width=10 | mark_link=γ Cen
| x%=53.6 | y%=51.0
}}
| caption=Location of γ Centauri (circled)
| caption=Location of γ Centauri (circled)
}}
}}
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}}
}}
{{Starbox character
{{Starbox character
| class = A1IV+<ref name=aj132_1_161/>&nbsp;(A0III/A0III)<ref name=schaaf/>
| class = A1IV+<ref name=aj132_1_161/>&nbsp;{{nowrap|(A1IV + A0IV)}}<ref name=Gray_Garrison_1987/>
| b-v = −0.01<ref name=clpl4_99/>
| b-v = −0.01<ref name=clpl4_99/>
| u-b = −0.01<ref name=clpl4_99/>
| u-b = −0.01<ref name=clpl4_99/>
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| p_error = 0.28
| p_error = 0.28
| parallax_footnote = <ref name=aaa474_2_653/>
| parallax_footnote = <ref name=aaa474_2_653/>
| absmag_v = –0.81<ref name=schaaf/>
| absmag_v = −0.81<ref name=schaaf/>
}}
}}
{{Starbox orbit
{{Starbox orbit
| reference = <ref name=Argyle_et_al_2015/>
| name=γ Centauri B
| name=γ Centauri B
⚫
| period = {{val|83.57|0.21}}
| reference = <ref name=aj122_6_3466/><ref name=orb6>{{cite web|url=http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/wds/orb6|title=Sixth Catalog of Orbits of Visual Binary Stars}}</ref>
⚫
| axis = {{val|0.869|0.011}}
⚫
| period = 83.57
| eccentricity = {{val|0.793|0.003}}
⚫
| axis = 0.869
| eccentricity = 0.793
| inclination = {{val|113.7|0.7}}
| inclination = 113.7
| node = {{val|2.6|0.7}}
⚫
| periastron = {{nowrap|1,931.25 ± 0.07}}
| node = 2.6
⚫
| periarg = {{val|187.9|1.5}}
⚫
| periastron = 1931.25
⚫
| periarg = 187.9
}}
}}
{{Starbox detail
{{Starbox detail
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| temperature = 9,082<ref name=aj132_1_161/>
| temperature = 9,082<ref name=aj132_1_161/>
| gravity = 3.52<ref name=aj132_1_161/>
| gravity = 3.52<ref name=aj132_1_161/>
| metal =
| metal = −0.29<ref name=aj132_1_161/>
| rotational_velocity =
| rotational_velocity =
| age =
| age =
}}
}}
{{Starbox catalog
{{Starbox catalog
| names=Muhlifain, [[Harvard Revised catalogue|HR]] 4819, [[Henry Draper catalogue|HD]] 110304, [[Bonner Durchmusterung|CD]]−48°7597, [[Smithsonian Astrophysical Observatory Star Catalog|SAO]] 223603, [[Washington Double Star Catalog|WDS]] 12415-4858, [[Hipparcos catalogue|HIP]] 61932, [[Boss General Catalogue|GC]] 17262, [[Catalog of Components of Double and Multiple Stars |CCDM]] J12415-4858.
| names = {{odlist | name=Muhlifain | B=γ Cen, Gam Cen | HR=4819 | HD=110304 | CD=−48°7597 | SAO=223603 | WDS=12415-4858 | HIP=61932 | GC=17262 | CCDM=J12415-4858 }}
}}
}}
{{Starbox reference
{{Starbox reference
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{{Starbox end}}
{{Starbox end}}


'''Gamma Centauri''' (γ Cen, γ Centauri) is a [[star]] in the southern [[constellation]] [[Centaurus]]. It has the proper name '''Muhlifain''',<ref>Kunitzsch, P., ''Arabische Sternnamen in Europa'', Otto Harrassowitz, [[Wiesbaden]], p.188.</ref> not to be confused with Muliphein, which is [[γ Canis Majoris]]; both names derive from the same Arabic root.
'''Gamma Centauri''', [[Romanization of Greek|Latinized]] from γ Centauri, is a [[binary star]] system in the [[Southern celestial hemisphere|southern]] [[constellation]] of [[Centaurus]]. It has the proper name '''Muhlifain''',<ref>{{cite book|author=Paul Kunitzsch|title=Arabische Sternnamen in Europa, von Paul Kunitzsch|url=https://books.google.com/books?id=qhtGQwAACAAJ|year=1959|page=188|publisher=O. Harrassowitz}}</ref> not to be confused with Muliphein, which is [[γ Canis Majoris]]; both names derive from the same Arabic root. The system is visible to the naked eye as a single point of light with a combined [[apparent visual magnitude]] of +2.17;<ref name=clpl4_99/> individually they are third-magnitude stars.<ref name=aaa356_141/>


Gamma Centauri is a [[double star]] located about {{Convert|130|ly|pc|abbr=off|lk=on}} from [[Earth]]. The combined [[apparent visual magnitude]] of the pair is +2.17,<ref name=clpl4_99/> although individually they are third magnitude stars.<ref name=aaa356_141/> The stellar classification of the pair is A1IV+,<ref name=aj132_1_161/> suggesting they are A-type [[subgiant]] stars in the process of becoming [[giant star|giants]]. Individually, their stellar classifications are sometimes listed as A0III, which would mean they have already become giants.<ref name=schaaf/>
This system is located at a distance of about {{Convert|130|ly|pc|abbr=off|lk=on}} from the [[Sun]] based on [[Stellar parallax|parallax]]. In 2000, the pair had an angular separation of 1.217 [[arcseconds]] with a [[position angle]] of 351.9°.<ref name=aaa356_141/> Their positions have been observed since 1897, which is long enough to estimate an [[orbital period]] of 84.5 years and a [[semimajor axis]] of 0.93 arcsecond.<ref name=aj122_6_3466/><ref name=Argyle_et_al_2015/> At the distance of this system, this is equivalent to a physical separation of about {{val|93|ul=AU}}.<ref name=kaler/>


In 2000, the pair had an angular separation of 1.217 [[arcsecond]]s with a [[position angle]] of 351.9°.<ref name=aaa356_141/> Their positions have been observed since 1897, which is long enough to estimate an orbital period of 84.5 years and a [[semimajor axis]] of 0.93 arcseconds.<ref name=aj122_6_3466/> At the distance of this system, this is equivalent to a linear distance of about 93 [[Astronomical Unit]]s.<ref name=kaler/> The star [[Tau Centauri]] is relatively close to Gamma Centauri, with an estimated separation of {{Convert|1.72|ly|pc}}.<ref name=apjs192_1_2/>
The combined [[stellar classification]] of the pair is A1IV+;<ref name=aj132_1_161/> when they are separated out they have individual classes of A1IV and A0IV,<ref name=Gray_Garrison_1987/> suggesting they are [[A-type star|A-type]] [[subgiant]] stars in the process of becoming [[giant star|giants]]. The star [[Tau Centauri]] is relatively close to Gamma Centauri, with an estimated separation of {{convert|1.72|ly|pc|abbr=off}}.<ref name=apjs192_1_2/> There is a 98% chance that they are [[Comoving and proper distances|co-moving stars]].<ref name=Argyle_et_al_2015/>


==Etymology==
==Etymology==


In [[Chinese language|Chinese]], {{lang|zh|庫樓}} ({{lang|zh-Latn|Kù Lóu}}), meaning ''[[Horn (Chinese constellation)|Arsenal]]'', refers to an asterism consisting of γ Centauri, [[Zeta Centauri|ζ Centauri]], [[Eta Centauri|η Centauri]], [[Theta Centauri|θ Centauri]], [[2 Centauri]], [[HD 117440]], [[Xi¹ Centauri|ξ<sup>1</sup> Centauri]], [[Tau Centauri|τ Centauri]], [[D Centauri]] and [[Sigma Centauri|σ Centauri]].<ref>{{zh icon}} ''中國星座神話'', written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.</ref> Consequently, γ Centauri itself is known as {{lang|zh|庫樓七}} ({{lang|zh-Latn|Kù Lóu qī}}, {{lang-en|the Seventh Star of Arsenal}}.)<ref>{{zh icon}} [http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_m.htm 香港太空館 - 研究資源 - 亮星中英對照表] {{wayback|url=http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_m.htm |date=20110130063012 }}, Hong Kong Space Museum. Accessed on line November 23, 2010.</ref>
In [[Chinese astronomy]], {{lang|zh|庫樓}} ({{lang|zh-Latn|Kù Lóu}}), meaning ''[[Horn (Chinese constellation)|Arsenal]]'', refers to an [[Asterism (astronomy)|asterism]] consisting of γ Centauri, [[ζ Centauri]], [[η Centauri]], [[θ Centauri]], [[2 Centauri]], [[HD 117440]], [[Xi1 Centauri|ξ<sup>1</sup> Centauri]], [[τ Centauri]], [[D Centauri]] and [[σ Centauri]].<ref>{{in lang|zh}} ''中國星座神話'', written by 陳久金. Published by 台灣書房出版有限公司, 2005, {{ISBN|978-986-7332-25-7}}.</ref> Consequently, the [[Chinese star names|Chinese name]] for γ Centauri itself is {{lang|zh|庫樓七}} ({{lang|zh-Latn|Kù Lóu qī}}, {{langx|en|the Seventh Star of Arsenal}}).<ref>{{in lang|zh}} [http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_m.htm 香港太空館 - 研究資源 - 亮星中英對照表] {{webarchive |url=https://web.archive.org/web/20110130063012/http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_m.htm |date=January 30, 2011 }}, Hong Kong Space Museum. Accessed online November 23, 2010.</ref>


The people of [[Aranda people|Aranda]] and [[Luritja]] tribe around [[Hermannsburg]], [[Central Australia]] named '''Iritjinga''', "The Eagle-hawk", a quadrangular arrangement comprising this star, [[Delta Centauri|δ Cen]] (Ma Wei), [[Delta Crucis|δ Cru]] (Palida) and [[Gamma Crucis|γ Cru]] (Gacrux), .<ref>p. 8, [https://books.google.com/books?id=XoeiJxMmXZ8C&pg ''Explorers of the southern sky: a history of Australian astronomy''], Raymond Haynes, Cambridge, Cambridge University Press, 1996.</ref>
The people of [[Arrernte people|Aranda]] and [[Luritja]] tribe around [[Hermannsburg, Northern Territory|Hermannsburg]], [[Central Australia]] named a quadrangular arrangement comprising this star, [[Delta Centauri|δ Cen]] (Ma Wei), [[Imai (star)|δ Cru]] (Imai) and γ Cru ([[Gacrux]]) as ''Iritjinga'' ("The Eagle-hawk").<ref>{{citation|author1=Raymond Haynes|author2=Roslynn D. Haynes|author3=David Malin|author4=Richard McGee|title=Explorers of the Southern Sky: A History of Australian Astronomy|url=https://books.google.com/books?id=XoeiJxMmXZ8C|year=1996|publisher=Cambridge University Press|location=Cambridge|isbn=978-0-521-36575-8|page=8}}</ref>


== References ==
== References ==
{{reflist|30em|refs=
{{reflist|30em|refs=


<ref name=aaa474_2_653>{{cite journal | first=F. | last=van Leeuwen |date=November 2007 | title=Validation of the new Hipparcos reduction | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 |arxiv = 0708.1752 }}</ref>
<ref name=aaa474_2_653>{{cite journal | first=F. | last=van Leeuwen |date=November 2007 | title=Validation of the new Hipparcos reduction | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 |arxiv = 0708.1752 | s2cid=18759600 }}</ref>


<ref name=rgcrv>{{cite book | last=Evans | first=D. S. | date=June 20–24, 1966 | editors=Batten, Alan Henry; Heard, John Frederick | title=The Revision of the General Catalogue of Radial Velocities | booktitle=Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30 | location=University of Toronto | publisher=International Astronomical Union | bibcode=1967IAUS...30...57E }}</ref>
<ref name=rgcrv>{{cite book | last=Evans | first=D. S. | date=June 20–24, 1966 | editor1=Batten, Alan Henry |editor2=Heard, John Frederick | title=The Revision of the General Catalogue of Radial Velocities | work=Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30 | volume=30 | page=57 | location=University of Toronto | publisher=[[International Astronomical Union]] | bibcode=1967IAUS...30...57E }}</ref>


<ref name=aj132_1_161>{{cite journal | display-authors=1 | last1=Gray | first1=R. O. | last2=Corbally | first2=C. J. | last3=Garrison | first3=R. F. | last4=McFadden | first4=M. T. | last5=Bubar | first5=E. J. | last6=McGahee | first6=C. E. | last7=O'Donoghue | first7=A. A. | last8=Knox | first8=E. R. | title=Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample | journal=The Astronomical Journal | volume=132 | issue=1 | pages=161–170 |date=July 2006 | doi=10.1086/504637 | bibcode=2006AJ....132..161G |arxiv = astro-ph/0603770 }}</ref>
<ref name=aj132_1_161>{{cite journal | display-authors=1 | last1=Gray | first1=R. O. | last2=Corbally | first2=C. J. | last3=Garrison | first3=R. F. | last4=McFadden | first4=M. T. | last5=Bubar | first5=E. J. | last6=McGahee | first6=C. E. | last7=O'Donoghue | first7=A. A. | last8=Knox | first8=E. R. | title=Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample | journal=The Astronomical Journal | volume=132 | issue=1 | pages=161–170 |date=July 2006 | doi=10.1086/504637 | bibcode=2006AJ....132..161G |arxiv = astro-ph/0603770 | s2cid=119476992 }}</ref>


<ref name=apjs192_1_2>{{cite journal | last1=Shaya | first1=Ed J. | last2=Olling | first2=Rob P. | title=Very Wide Binaries and Other Comoving Stellar Companions: A Bayesian Analysis of the Hipparcos Catalogue | journal=The Astrophysical Journal Supplement | volume=192 | issue=1 | page=2 |date=January 2011 | doi=10.1088/0067-0049/192/1/2 | bibcode=2011ApJS..192....2S |arxiv = 1007.0425 }}</ref>
<ref name=apjs192_1_2>{{cite journal | last1=Shaya | first1=Ed J. | last2=Olling | first2=Rob P. | title=Very Wide Binaries and Other Comoving Stellar Companions: A Bayesian Analysis of the Hipparcos Catalogue | journal=The Astrophysical Journal Supplement | volume=192 | issue=1 | page=2 |date=January 2011 | doi=10.1088/0067-0049/192/1/2 | bibcode=2011ApJS..192....2S |arxiv = 1007.0425 | s2cid=119226823 }}</ref>


<ref name=aaa356_141>{{cite journal | last1=Fabricius | first1=C. | last2=Makarov | first2=V. V. | title=Two-colour photometry for 9473 components of close Hipparcos double and multiple stars | journal=Astronomy and Astrophysics | volume=356 | pages=141–145 |date=April 2000 | bibcode=2000A&A...356..141F }}</ref>
<ref name=aaa356_141>{{cite journal | last1=Fabricius | first1=C. | last2=Makarov | first2=V. V. | title=Two-colour photometry for 9473 components of close Hipparcos double and multiple stars | journal=Astronomy and Astrophysics | volume=356 | pages=141–145 |date=April 2000 | bibcode=2000A&A...356..141F }}</ref>
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<ref name=clpl4_99>{{Cite journal | last1=Johnson | display-authors=1 | first1=H. L. | last2=Iriarte | first2=B. | last3=Mitchell | first3=R. I. | last4=Wisniewskj | first4=W. Z. | title=UBVRIJKL photometry of the bright stars | journal=Communications of the Lunar and Planetary Laboratory | volume=4 | issue=99 | pages=99 | date=1966 | bibcode=1966CoLPL...4...99J }}</ref>
<ref name=clpl4_99>{{Cite journal | last1=Johnson | display-authors=1 | first1=H. L. | last2=Iriarte | first2=B. | last3=Mitchell | first3=R. I. | last4=Wisniewskj | first4=W. Z. | title=UBVRIJKL photometry of the bright stars | journal=Communications of the Lunar and Planetary Laboratory | volume=4 | issue=99 | pages=99 | date=1966 | bibcode=1966CoLPL...4...99J }}</ref>


<ref name=schaaf>{{cite book | first1=Fred | last1=Schaaf | title=The brightest stars: discovering the universe through the sky's most brilliant stars | journal=The Brightest Stars: Discovering the Universe through the Sky's Most Brilliant Stars | publisher=John Wiley and Sons | date=2008 | isbn=0-471-70410-5 | page=262 | bibcode=2008bsdu.book.....S }}</ref>
<ref name=schaaf>{{cite book | first1=Fred | last1=Schaaf | title=The brightest stars: discovering the universe through the sky's most brilliant stars | publisher=[[John Wiley and Sons]] | date=2008 | isbn=978-0-471-70410-2 | page=262 | bibcode=2008bsdu.book.....S }}</ref>


<ref name=aj122_6_3466>{{cite journal | display-authors=1 | last1=Mason | first1=Brian D. | last2=Wycoff | first2=Gary L. | last3=Hartkopf | first3=William I. | last4=Douglass | first4=Geoffrey G. | last5=Worley | first5=Charles E. | title=The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog | journal=The Astronomical Journal | volume=122 | issue=6 | pages=3466–3471 |date=December 2001 | doi=10.1086/323920 | bibcode=2001AJ....122.3466M }}</ref>
<ref name=aj122_6_3466>{{cite journal | display-authors=1 | last1=Mason | first1=Brian D. | last2=Wycoff | first2=Gary L. | last3=Hartkopf | first3=William I. | last4=Douglass | first4=Geoffrey G. | last5=Worley | first5=Charles E. | title=The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog | journal=The Astronomical Journal | volume=122 | issue=6 | pages=3466–3471 |date=December 2001 | doi=10.1086/323920 | bibcode=2001AJ....122.3466M | doi-access=free }}</ref>

⚫
<ref name=kaler>{{cite web | first1=James B. | last1=Kaler | title=MUHLIFAIN (Gamma Centauri) | work=Stars | publisher=[[University of Illinois]] | url=http://stars.astro.illinois.edu/sow/muhlifain.html | access-date=2011-12-31 }}</ref>

<ref name=Gray_Garrison_1987>{{cite journal
| title=The Early A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation
| last1=Gray | first1=R. O. | last2=Garrison | first2=R. F.
| journal=Astrophysical Journal Supplement
| volume=65 | page=581 | date=December 1987
| doi=10.1086/191237 | bibcode=1987ApJS...65..581G | doi-access=free }}</ref>

<ref name=Argyle_et_al_2015>{{cite journal
| title=Micrometric measures and orbits of southern visual double stars
| display-authors=1 | last1=Argyle | first1=R. W.
| last2=Alzner | first2=A. | last3=van Leeuwen | first3=F.
| journal=Astronomische Nachrichten
| volume=336 | issue=4 | pages=378–387 | date=May 2015
| doi=10.1002/asna.201412166 | bibcode=2015AN....336..378A | doi-access=free }}</ref>


⚫
<ref name=kaler>{{cite web | first1=James B. | last1=Kaler | title=MUHLIFAIN (Gamma Centauri) | work=Stars | publisher=University of Illinois | url=http://stars.astro.illinois.edu/sow/muhlifain.html | accessdate=2011-12-31 }}</ref>


}}
}}
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{{Stars of Centaurus}}
{{Stars of Centaurus}}


⚫
{{DEFAULTSORT:Gamma Centauri}}
[[Category:Centaurus (constellation)]]
<!-- Properties -->
⚫
[[Category:Bayer objects|Centauri, Gamma]]
⚫
[[Category:A-type subgiants]]
[[Category:Binary stars]]
[[Category:Binary stars]]
<!-- Other -->
⚫
[[Category:A-type giants]]
[[Category:HR objects|4819]]
[[Category:Centaurus]]
[[Category:Hipparcos objects|061932]]
[[Category:Bayer objects|Centauri, Gamma]]
[[Category:Durchmusterung objects|BD-48 7597]]
[[Category:Henry Draper Catalogue objects|110304]]
[[Category:Henry Draper Catalogue objects|110304]]
[[Category:Durchmusterung objects|BD−48 7597]]
[[Category:Hipparcos objects|061932]]
[[Category:Bright Star Catalogue objects|4819]]
⚫
[[Category:TIC objects]]

Latest revision as of 09:20, 26 October 2024

This article is about γ Centauri. Not to be confused with Y Centauri or y Centauri.
Gamma Centauri
Location of γ Centauri (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Centaurus
Right ascension 12h 41m 31.04008s[1]
Declination −48° 57′ 35.5375″[1]
Apparent magnitude (V) +2.17[2] (+2.85/+2.95)[3]
Characteristics
Spectral type A1IV+[4] (A1IV + A0IV)[5]
U−B color index −0.01[2]
B−V color index −0.01[2]
Astrometry
Radial velocity (Rv)−5.5[6] km/s
Proper motion (μ) RA: −185.72[1] mas/yr
Dec.: +5.79[1] mas/yr
Parallax (π)25.06 ± 0.28 mas[1]
Distance130 ± 1 ly
(39.9 ± 0.4 pc)
Absolute magnitude (MV)−0.81[7]
Orbit[8]
Companionγ Centauri B
Period (P)83.57±0.21 yr
Semi-major axis (a)0.869±0.011″
Eccentricity (e)0.793±0.003
Inclination (i)113.7±0.7°
Longitude of the node (Ω)2.6±0.7°
Periastron epoch (T)1,931.25 ± 0.07
Argument of periastron (ω)
(secondary)		187.9±1.5°
Details
Mass2.91[9] M☉
Surface gravity (log g)3.52[4] cgs
Temperature9,082[4] K
Metallicity−0.29[4]
Other designations
Muhlifain, γ Cen, Gam Cen, CD−48°7597, GC 17262, HD 110304, HIP 61932, HR 4819, SAO 223603, CCDM J12415-4858, WDS 12415-4858
Database references
SIMBADdata

Gamma Centauri, Latinized from γ Centauri, is a binary star system in the southern constellation of Centaurus. It has the proper name Muhlifain,[10] not to be confused with Muliphein, which is γ Canis Majoris; both names derive from the same Arabic root. The system is visible to the naked eye as a single point of light with a combined apparent visual magnitude of +2.17;[2] individually they are third-magnitude stars.[3]

This system is located at a distance of about 130 light-years (40 parsecs) from the Sun based on parallax. In 2000, the pair had an angular separation of 1.217 arcseconds with a position angle of 351.9°.[3] Their positions have been observed since 1897, which is long enough to estimate an orbital period of 84.5 years and a semimajor axis of 0.93 arcsecond.[11][8] At the distance of this system, this is equivalent to a physical separation of about 93 AU.[12]

The combined stellar classification of the pair is A1IV+;[4] when they are separated out they have individual classes of A1IV and A0IV,[5] suggesting they are A-type subgiant stars in the process of becoming giants. The star Tau Centauri is relatively close to Gamma Centauri, with an estimated separation of 1.72 light-years (0.53 parsecs).[9] There is a 98% chance that they are co-moving stars.[8]

Etymology

[edit]

In Chinese astronomy, 庫樓 (Kù Lóu), meaning Arsenal, refers to an asterism consisting of γ Centauri, ζ Centauri, η Centauri, θ Centauri, 2 Centauri, HD 117440, ξ1 Centauri, τ Centauri, D Centauri and σ Centauri.[13] Consequently, the Chinese name for γ Centauri itself is 庫樓七 (Kù Lóu qī, English: the Seventh Star of Arsenal).[14]

The people of Aranda and Luritja tribe around Hermannsburg, Central Australia named a quadrangular arrangement comprising this star, δ Cen (Ma Wei), δ Cru (Imai) and γ Cru (Gacrux) as Iritjinga ("The Eagle-hawk").[15]

References

[edit]
  1. ^ a b c d e van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
  2. ^ a b c d Johnson, H. L.; et al. (1966). "UBVRIJKL photometry of the bright stars". Communications of the Lunar and Planetary Laboratory. 4 (99): 99. Bibcode:1966CoLPL...4...99J.
  3. ^ a b c Fabricius, C.; Makarov, V. V. (April 2000). "Two-colour photometry for 9473 components of close Hipparcos double and multiple stars". Astronomy and Astrophysics. 356: 141–145. Bibcode:2000A&A...356..141F.
  4. ^ a b c d e Gray, R. O.; et al. (July 2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv:astro-ph/0603770. Bibcode:2006AJ....132..161G. doi:10.1086/504637. S2CID 119476992.
  5. ^ a b Gray, R. O.; Garrison, R. F. (December 1987). "The Early A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation". Astrophysical Journal Supplement. 65: 581. Bibcode:1987ApJS...65..581G. doi:10.1086/191237.
  6. ^ Evans, D. S. (June 20–24, 1966). Batten, Alan Henry; Heard, John Frederick (eds.). The Revision of the General Catalogue of Radial Velocities. Vol. 30. University of Toronto: International Astronomical Union. p. 57. Bibcode:1967IAUS...30...57E. {{cite book}}: |work= ignored (help)
  7. ^ Schaaf, Fred (2008). The brightest stars: discovering the universe through the sky's most brilliant stars. John Wiley and Sons. p. 262. Bibcode:2008bsdu.book.....S. ISBN 978-0-471-70410-2.
  8. ^ a b c Argyle, R. W.; et al. (May 2015). "Micrometric measures and orbits of southern visual double stars". Astronomische Nachrichten. 336 (4): 378–387. Bibcode:2015AN....336..378A. doi:10.1002/asna.201412166.
  9. ^ a b Shaya, Ed J.; Olling, Rob P. (January 2011). "Very Wide Binaries and Other Comoving Stellar Companions: A Bayesian Analysis of the Hipparcos Catalogue". The Astrophysical Journal Supplement. 192 (1): 2. arXiv:1007.0425. Bibcode:2011ApJS..192....2S. doi:10.1088/0067-0049/192/1/2. S2CID 119226823.
  10. ^ Paul Kunitzsch (1959). Arabische Sternnamen in Europa, von Paul Kunitzsch. O. Harrassowitz. p. 188.
  11. ^ Mason, Brian D.; et al. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.
  12. ^ Kaler, James B. "MUHLIFAIN (Gamma Centauri)". Stars. University of Illinois. Retrieved 2011-12-31.
  13. ^ (in Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
  14. ^ (in Chinese) 香港太空館 - 研究資源 - 亮星中英對照表 Archived January 30, 2011, at the Wayback Machine, Hong Kong Space Museum. Accessed online November 23, 2010.
  15. ^ Raymond Haynes; Roslynn D. Haynes; David Malin; Richard McGee (1996), Explorers of the Southern Sky: A History of Australian Astronomy, Cambridge: Cambridge University Press, p. 8, ISBN 978-0-521-36575-8
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