| absmag_v = −3.3[12]
}}{{Starbox detail
| mass = {{nowrap|8.8 ± 0.2}}[13]
| radius = 6.6[14]
| luminosity = 10,000[12]
| temperature = 24,090[16]
| gravity = 3.76[12]
| metal_fe = {{nowrap|−0.35 ± 0.11}}[7]
| rotational_velocity = 92[4]
| age_myr = {{nowrap|24.6 ± 2.7}}[13]
}}{{Starbox catalog
| names = CD−42° 9853, FK5 552, HD 132058, HIP 73273 , HR 5571, SAO 225335.[21]
}}{{Starbox reference
|Simbad=bet+Lup
}}{{Starbox end}}Beta Lupi (β Lupi, β Lup), or Kekouan, is a star in the southern constellation of Lupus. It has an apparent visual magnitude of 2.7,[3] making it readily visible to the naked eye. Based upon parallax measurements, this star is located at a distance of about {{Convert|383|ly|pc|abbr=off|lk=on}} from Earth.[3]Properties
The stellar classification of B2 III indicates this is a giant star.[4] The effective temperature of the star's outer envelope is 24,090 K,[16] giving it the blue-white hue of a B-type star.[26] With an age of around 25 million years,[13] it is near the end of its hydrogen phase, where hydrogen is fused into the element helium, and transferring into a red supergiant star. At about 8.8[13] solar masses, it may have enough mass to end its life as a Type II supernova, but there is the possibility of Beta Lupi becoming a white dwarf.[29]
This is a multi-period Beta Cephei variable with a dominant oscillation period of 0.232 days.[7] It is a proper motion member of the Upper-Centaurus Lupus sub-group in the Scorpius-Centaurus OB association, the nearest such co-moving association of massive stars to the Sun.[12] Beta Lupi has a high proper motion of more than 50 mas per year, suggesting a significant transverse velocity.[32]
It lies close to the supernova remnant SN 1006.{{Citation needed|date=January 2012}}
Name
In Chinese, {{lang|zh|騎官}} ({{lang|zh-Latn|Qí Guān}}), meaning Imperial Guards, refers to an asterism consisting of β Lupi, γ Lupi, δ Lupi, κ Centauri, λ Lupi, ε Lupi, μ Lup, π Lupi, ο Lupi and α Lupi.[1] Consequently, β Lupi itself is known as {{lang|zh|騎官四}} ({{lang|zh-Latn|Qí Guān sì}}, {{lang-en|the Fourth Star of Imperial Guards}}.).[2] From the French rendering of this Chinese name derives the traditional European name Kekouan (Ke Kwan).[3]
See also
- Traditional Chinese star names#Lupus
References
1. ^{{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}}.
2. ^{{zh icon}} 香港太空館 - 研究資源 - 亮星中英對照表 {{webarchive|url=https://web.archive.org/web/20110129031951/http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_h_l.htm |date=2011-01-29 }}, Hong Kong Space Museum. Accessed on line November 23, 2010.]
3. ^Richard Hinckley Allen: Star Names — Their Lore and Meaning: Lupus
4. ^1 2 3 {{citation | display-authors=1 | title=Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions | last1=Wielen | first1=R. | last2=Schwan | first2=H. | last3=Dettbarn | first3=C. | last4=Lenhardt | first4=H. | last5=Jahreiß | first5=H. | last6=Jährling | first6=R. | publisher=Astronomisches Rechen-Institut Heidelberg | issue=35 | date=1999 | bibcode=1999VeARI..35....1W }}
5. ^1 2 {{citation | last1=Gutierrez-Moreno | first1=Adelina | last2=Moreno | first2=Hugo | title=A photometric investigation of the Scorpio-Centaurus association | journal=Astrophysical Journal Supplement | volume=15 | page=459 |date=June 1968 | bibcode=1968ApJS...15..459G | doi=10.1086/190168 }}
6. ^1 2 {{citation | display-authors=1 | last1=Zorec | first1=J. | last2=Cidale | first2=L. | last3=Arias | first3=M. L. | last4=Frémat | first4=Y. | last5=Muratore | first5=M. F. | last6=Torres | first6=A. F. | last7=Martayan | first7=C. | title=Fundamental parameters of B supergiants from the BCD system. I. Calibration of the (λ_1, D) parameters into Teff | journal=Astronomy and Astrophysics | volume=501 | issue=1 | pages=297–320 |date=July 2009 | doi=10.1051/0004-6361/200811147 | bibcode=2009A&A...501..297Z |arxiv = 0903.5134 }}
7. ^1 2 3 4 {{citation | display-authors=1 | last1=Jilinski | first1=E. | last2=Daflon | first2=S. | last3=Cunha | first3=K. | last4=de La Reza | first4=R. | title=Radial velocity measurements of B stars in the Scorpius-Centaurus association | journal=Astronomy and Astrophysics | volume=448 | issue=3 |date=March 2006 | pages=1001–1006 | doi=10.1051/0004-6361:20041614 | bibcode=2006A&A...448.1001J|arxiv = astro-ph/0601643 }}
8. ^1 2 3 {{citation | last1=Daszyńska-Daszkiewicz | first1=J. | last2=Niemczura | first2=E. | title=Metallicity of mono- and multiperiodic β Cephei stars | journal=Astronomy and Astrophysics | volume=433 | issue=3 | pages=1031–1035 |date=April 2005 | doi=10.1051/0004-6361:20040397 | bibcode=2005A&A...433.1031D |arxiv = astro-ph/0410442 }}
9. ^1 {{citation | last1=Jiménez-Esteban | first1=F. M. | last2=Caballero | first2=J. A. | last3=Solano | first3=E. | title=Identification of blue high proper motion objects in the Tycho-2 and 2MASS catalogues using Virtual Observatory tools | journal=Astronomy and Astrophysics | volume=525 | page=A29 |date=January 2011 | doi=10.1051/0004-6361/201015223 | bibcode=2011A&A...525A..29J |arxiv = 1009.3466 }}
10. ^1 {{citation |title=The Colour of Stars |date=December 21, 2004 |work=Australia Telescope, Outreach and Education |publisher=Commonwealth Scientific and Industrial Research Organisation |url=http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html |accessdate=2012-01-16 |deadurl=yes |archiveurl=https://www.webcitation.org/6630AbtJZ?url=http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html |archivedate=2012-03-10 |df= }}
11. ^1 {{citation | title=bet Lup -- Variable Star | work=SIMBAD | publisher=Centre de Données astronomiques de Strasbourg | url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=Beta+Lupi | accessdate=2012-01-16 }}
12. ^1 {{citation | url=http://www.astro.illinois.edu/~jkaler/sow/betalup.html | title=Beta Lupi | last=Kaler | first=James B. | date=2007 | publisher=University of Illinois | work=Stars | accessdate=2009-07-03 | deadurl=yes | archiveurl=https://web.archive.org/web/20110716072207/http://www.astro.illinois.edu/~jkaler/sow/betalup.html | archivedate=2011-07-16 | df= }}
13. ^1 2 3 4 {{citation | last1=de Geus | first1=E. J. | last2=de Zeeuw | first2=P. T. | last3=Lub | first3=J. | title=Physical parameters of stars in the Scorpio-Centaurus OB association | journal=Astronomy and Astrophysics | volume=216 | issue=1-2 | pages=44–61 |date=June 1989 | bibcode=1989A&A...216...44D }}
14. ^1 2 3 4 {{citation | 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 }}
15. ^1 {{citation | display-authors=1 | last1=Underhill | first1=A. B. | last2=Divan | first2=L. | last3=Prevot-Burnichon | first3=M.-L. | last4=Doazan | first4=V. | title=Effective temperatures, angular diameters, distances and linear radii for 160 O and B stars | journal=Monthly Notices of the Royal Astronomical Society | volume=189 | pages=601–605 |date=November 1979 | bibcode=1979MNRAS.189..601U | doi=10.1093/mnras/189.3.601}}