Sigma Columbae
{{Short description|Star in the constellation Columba}}
{{Starbox begin
| name = Sigma Columbae
}}
{{Starbox observe
| epoch = J2000.0
| constell = Columba
| dec = {{DEC|−31|22|56.7846}}
}}
{{Starbox character
| u-b =
| variable =
}}
{{Starbox astrometry
| radial_v = {{Val|+19.4|2.9}}
| parallax = 1.96
| p_error = 0.24
}}
{{Starbox detail
| source =
| radius =
| rotational_velocity = {{Val|73.4|3.7}}
}}
{{Starbox catalog
| names = {{odlist | B=σ Col | CD=−31°2848 | HD=40248 | HIP=28098 | HR=2092 | SAO=196330 }}
}}
{{Starbox reference
| Simbad = sig+Col
}}
{{Starbox end}}
Sigma Columbae, Latinized from σ Columbae, is a solitary, yellow-white hued star in the southern constellation of Columba. It is faintly visible to the naked eye with an apparent visual magnitude of 5.51. Based upon an annual parallax shift of 1.96 mas as seen from Earth, this star is located roughly 1,700 light years from the Sun.
At an age of about 400 million years, the spectrum of this star suggests this is an evolved F-type giant with a stellar classification of F2 III. It is spinning with a projected rotational velocity of about 74 km/s, which is giving the star an oblate shape with an equatorial bulge that is 10% larger than the polar radius. It has 3.79 times the mass of the Sun and is radiating 1,312 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 6,820 K.
References
{{reflist|refs=
| 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 | s2cid=18759600 | postscript=. }}
| 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 | s2cid=119257644 | postscript=. }}
| 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 | doi-access=free | bibcode=2008MNRAS.389..869E
| arxiv=0806.2878 | s2cid=14878976 | postscript=. }}
| last1=Casagrande | first1=L. | last2=Schönrich | first2=R.
| last3=Asplund | first3=M. | last4=Cassisi | first4=S.
| last5=Ramírez | first5=I. | last6=Meléndez | first6=J.
| last7=Bensby | first7=T. | last8=Feltzing | first8=S.
| title=New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey
| journal=Astronomy & Astrophysics | display-authors=1
| volume=530 | issue=A138 | pages=21 | date=2011
| doi=10.1051/0004-6361/201016276 | bibcode=2011A&A...530A.138C
| arxiv=1103.4651 | s2cid=56118016 | postscript=. }}
| display-authors=1 | last1=McDonald | first1=I.
| last2=Zijlstra | first2=A. A. | last3=Boyer | first3=M. L.
| title=Fundamental Parameters and Infrared Excesses of Hipparcos Stars
| journal=Monthly Notices of the Royal Astronomical Society
| volume=427 | issue=1 | pages=343–57 | date=2012
| bibcode=2012MNRAS.427..343M | doi=10.1111/j.1365-2966.2012.21873.x
| doi-access=free | arxiv=1208.2037 | s2cid=118665352 | postscript=. }}
| last1=van Belle, Gerard T.
| title=Interferometric observations of rapidly rotating stars
| journal=The Astronomy and Astrophysics Review
| volume=20 | issue=1 | page=51 |date=March 2012
| doi=10.1007/s00159-012-0051-2 | bibcode=2012A&ARv..20...51V
| postscript=. |arxiv=1204.2572 | s2cid=119273474
}}
| 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 | s2cid=59451347 | postscript=. }}
| last1=Ammler-von Eiff | first1=Matthias | last2=Reiners | first2=Ansgar
| title=New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?
| journal=Astronomy & Astrophysics | arxiv=1204.2459
| volume=542 | page=A116 | date=June 2012 | postscript=.
| doi=10.1051/0004-6361/201118724 | bibcode=2012A&A...542A.116A | s2cid=53666672 }}
| display-authors=1 | last1=Høg | first1=E.
| last2=Fabricius | first2=C. | last3=Makarov | first3=V. V.
| last4=Urban | first4=S. | last5=Corbin | first5=T.
| last6=Wycoff | first6=G. | last7=Bastian | first7=U.
| last8=Schwekendiek | first8=P. | last9=Wicenec | first9=A.
| title=The Tycho-2 catalogue of the 2.5 million brightest stars
| journal=Astronomy and Astrophysics
| volume=355 | pages=L27 | year=2000
| bibcode=2000A&A...355L..27H | postscript=. }}
| title=Michigan catalogue of two-dimensional spectral types for the HD stars
| volume=3 | last1=Houk | first1=Nancy | postscript=.
| publication-place=Ann Arbor, Michigan
| publisher=Dept. of Astronomy, University of Michigan
| date=1979 | bibcode=1982mcts.book.....H }}
| title=sig Col | accessdate=2017-08-28 | postscript=. }}
}}
{{Stars of Columba|state=collapsed}}
{{DEFAULTSORT:Sigma Columbae}}
Category:Columba (constellation)