Beta Sextantis
{{short description|Star in the constellation Sextans}}
{{Starbox begin
| name = β Sextantis
}}
{{Starbox image
| image = 250px
| caption = A light curve for Beta Sextantis, plotted from TESS data,
}}
{{Starbox observe
| epoch = J2000.0
| constell = Sextans
}}
{{Starbox character
| type = main sequence
| class = B6 V or B5 IV/V
| r-i =
| variable = α2 CVn
}}
{{Starbox astrometry
| parallax = 8.9613
| p_error = 0.2448
}}
{{Starbox detail
| rotational_velocity = {{Val|85|4}}
| rotation =
}}
{{Starbox catalog
| names = {{odlist | B=β Sex | F=30 Sextantis | BD=+00°2663 | FK5=2841 | HD=90994 | HIP=51437 | HR=4119 | SAO=137608 }}
}}
{{Starbox reference
| Simbad = bet+Sex
}}
{{starbox end}}
Beta Sextantis, Latinized from β Sextantis, is a variable star in the equatorial constellation of Sextans. With an apparent visual magnitude of 5.07, it is faintly visible to the naked eye on a dark night. According to the Bortle scale, it can be viewed from brighter lit suburban skies. The distance to this star, based upon an annual parallax shift of 8.96 mas, is around 364 light years.
This star served as a primary standard in the MK spectral classification system with a stellar classification of B6 V, indicating that it is a B-type main sequence star. However, Houk and Swift (1999) list a classification of B5 IV/V, suggesting it may be transitioning into a subgiant star. It has served as a uvby photometric standard, but is also categorized as an Alpha2 Canum Venaticorum variable with a suspected period of 15.4 days. This lengthy a period conflicts with a relatively high projected rotational velocity of 85 km/s, leaving the explanation for the variance unresolved.
References
{{reflist|refs=
{{Cite DR2|3782940437640705408}}
| title=MAST: Barbara A. Mikulski Archive for Space Telescopes
| url=https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html
| publisher=Space Telescope Science Institute | access-date=27 August 2024}}
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| bibcode=1986A&AS...63..403M | postscript=. }}
| title=Michigan catalogue of two-dimensional spectral types for the HD Stars
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| journal=Michigan Spectral Survey
| publisher=Department of Astronomy, University of Michigan
| publication-place=Ann Arbor, Michigan | volume=5 | year=1999
| bibcode=1999MSS...C05....0H | postscript=. }}
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| issue=2 | doi=10.1051/0004-6361:20000451 | bibcode=2001A&A...367..521P
| arxiv=astro-ph/0012289 | s2cid=425754 | postscript=. }}
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| last1=Hempel | first1=M. | last2=Holweger | first2=H.
| journal=Astronomy and Astrophysics | postscript=.
| volume=408 | pages=1065–1076 | date=September 2003
| issue=3 | doi=10.1051/0004-6361:20030889 | bibcode=2003A&A...408.1065H | doi-access=free }}
| 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=. }}
| 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 | arxiv=1208.2037
| doi=10.1111/j.1365-2966.2012.21873.x | doi-access=free | s2cid=118665352 | postscript=. }}
| display-authors=1 | last1=Crawford | first1=D. L.
| last2=Barnes | first2=J. V. | last3=Golson | first3=J. C.
| title=Four-color, H-beta, and UBV photometry for bright B-type stars in the northern hemisphere
| journal=The Astronomical Journal
| year=1971 | pages=1058 | volume=76
| bibcode=1971AJ.....76.1058C | doi=10.1086/111220
| postscript=. }}
| title=bet Sex -- Variable Star of alpha2 CVn type
| work=SIMBAD Astronomical Database
| publisher=Centre de Données astronomiques de Strasbourg
| url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=bet+Sex
| accessdate=2016-12-13 | postscript=. }}
}}
{{Stars of Sextans|state=collapsed}}
{{DEFAULTSORT:Beta Sextantis}}
Category:Alpha2 Canum Venaticorum variables
Category:B-type main-sequence stars