| absmag_v = −1.18[12]
}}{{Starbox orbit
| reference = [5]
| period = 258
| axis = 2.576
| eccentricity = 0.931
}}{{Starbox detail
| source =
| component1 = γ Cir A
| temperature2 = 4,786[14]
| component2 = γ Cir B
| mass = {{Val|6.0|0.3}}[15]
| temperature = 15,135[14]
| gravity =
| metal_fe =
| rotational_velocity =
| age_myr = {{Val|63.1|19.6}}[15]
}}{{Starbox catalog
| names = γ Cir, CPD−58° 5908, HIP 75323, HR 5704, SAO 242463.[18]
| component1 = γ Cir A
| names1 = HD 136415
| component2 = γ Cir B
| names2 = HD 136416
}}{{Starbox reference
| Simbad = gam+Cir | sn = γ Cir AB
| Simbad2 = gam+Cir+A | sn2 = γ Cir A
| Simbad3 = gam+Cir+B | sn3 = γ Cir B
}}{{Starbox end}}Gamma Circini, Latinized from γ Circini, is a star system located in the constellation Circinus. It was noted as a double star by Herschel in 1835, who estimated their separation as 1 arc second.[19] It is visible to the naked eye with an apparent visual magnitude of 4.51.[3] Based upon an annual parallax shift of 7.27 mas,[ is it located at a distance of approximately 450 light years.]
This is a wide binary star system and may even be a triple star.[14] The two visible components orbit each other with a preliminary estimated period of 258 years and a large eccentricity of 0.931.[5] As of 2014, the visible components have an angular separation of 0.80 arc seconds along a position angle of 359°.[4]
The primary star, component A, is a B-type subgiant star with a stellar classification of B5 VI.[5] Based upon isochrone curve fitting it is hypothesized to be a pair of matching B5 stars,[14] and is a Be variable with an uncertain maximum.[7] It has an effective temperature of 15,135[14] K and an estimated mass six[15] times that of the Sun. The companion, component B, is an F-type main sequence star with a stellar classification of F8 V.[3] It has an effective temperature of 4,786[14] K.
References
1. ^1 {{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=. }}
2. ^1 2 {{citation | display-authors=1 | last1=Mason | first1=B. D. | last2=Wycoff | first2=G. L. | last3=Hartkopf | first3=W. I. | last4=Douglass | first4=G. G. | last5=Worley | first5=C. E. | title=The Washington Visual Double Star Catalog | year=2014 | bibcode=2001AJ....122.3466M | url=http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/wds | accessdate=2015-07-22 | doi = 10.1086/323920 | volume=122 | journal=The Astronomical Journal | pages=3466–3471}}
3. ^1 2 3 4 {{citation | title=The composite spectrum of gamma Circini | last1=Buscombe | first1=W. | last2=Barkstrom | first2=B. | journal=Monthly Notices of the Royal Astronomical Society | volume=152 | pages=37–45 | year=1971 | postscript=. | doi=10.1093/mnras/152.1.37 | bibcode=1971MNRAS.152...37B }}
4. ^1 2 3 4 5 6 {{citation | title=New and Confirmed Triple Systems with Luminous Cool Primaries and Hot Companions | last1=Parsons | first1=Sidney B. | postscript=. | journal=The Astronomical Journal | volume=127 | issue=5 | pages=2915–2930 | date=May 2004 | doi=10.1086/383546 | bibcode=2004AJ....127.2915P }}
5. ^1 2 3 4 {{citation | last1=Malkov | first1=O. Yu. | last2=Tamazian | first2=V. S. | last3=Docobo | first3=J. A. | last4=Chulkov | first4=D. A. | title=Dynamical masses of a selected sample of orbital binaries | journal=Astronomy & Astrophysics | display-authors=1 | volume=546 | pages=A69 | year=2012 | postscript=. | bibcode=2012A&A...546A..69M | doi=10.1051/0004-6361/201219774 }}
6. ^1 2 {{cite journal | title=The 74th Special Name-list of Variable Stars | display-authors=1 | last1=Kazarovets | first1=E. V. | last2=Samus | first2=N. N. | last3=Durlevich | first3=O. V. | last4=Frolov | first4=M. S. | last5=Antipin | first5=S. V. | last6=Kireeva | first6=N. N. | last7=Pastukhova | first7=E. N. | journal=Information Bulletin on Variable Stars | volume=4659 | pages=1 | year=1999 | bibcode=1999IBVS.4659....1K | postscript=. }}
7. ^1 2 3 {{citation | display-authors=1 | last1=Tetzlaff | first1=N. | last2=Neuhäuser | first2=R. | last3=Hohle | first3=M. M. | title=A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun | journal=Monthly Notices of the Royal Astronomical Society | volume=410 | issue=1 | pages=190–200 | date=January 2011 | doi=10.1111/j.1365-2966.2010.17434.x | bibcode=2011MNRAS.410..190T | arxiv=1007.4883 | postscript=. }}
8. ^1 {{citation | last1=de Bruijne | first1=J. H. J. | last2=Eilers | first2=A.-C. | title=Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project | journal=Astronomy & Astrophysics | volume=546 | id=A61 | pages=14 | date=October 2012 | doi=10.1051/0004-6361/201219219 | bibcode=2012A&A...546A..61D | arxiv=1208.3048 | postscript=. }}
9. ^1 {{citation | title=γ Circinus: a young visual binary with pre-main-sequence component(s)? | last1=Carette | first1=E. | last2=De Greve | first2=J. P. | last3=van Rensbergen | first3=W. | last4=Lampens | first4=P. | journal=Astronomy and Astrophysics | display-authors=1 | volume=296 | page=139 | date=April 1995 | bibcode=1995A&A...296..139C | postscript=. }}
10. ^1 {{cite simbad | title=* gam Cir | accessdate=2017-01-13 | postscript=. }}