| absmag_v= −0.10[11]
}}{{Starbox detail
| mass=2.76[12]
| radius=3.3[13]
| luminosity=133[11]
| temperature=10,250[13]
| metal_fe=+0.0[13]
| rotation=
| rotational_velocity=70[17]
| gravity={{Val|3.83|0.03}}[18]
| age_myr=293[12]
}}{{Starbox catalog
| names = {{odlist | B=σ Leo | F=77 Leo | BD=−06° 2437 | FK5=427 | HD=98664 | HIP=55434 | HR=4386 | SAO=118804 | GC=| LHS=}}[1]
}}{{Starbox reference
|Simbad=sig+Leo
}}{{Starbox end}}Sigma Leonis, Latinized from σ Leonis, is a blue-white hued star in the zodiac constellation Leo that is visible to the naked eye with an apparent visual magnitude of 4.0.[3] An annual parallax shift of 15.24 mas as seen from Earth provides a distance estimate of around 210 light years from the Sun. It is moving closer to the Sun with a radial velocity of –5 km/s.[7]Chini et al. (2012) list this as a single-lined spectroscopic binary system.[4] The visible component has a stellar classification of B9.5 Vs,[4] indicating it is a B-type main-sequence star. It is a suspected magnetic Ap star that shows an abundance anomaly with the element silicon.[25] Sigma Leonis has an estimated 2.76[12] times the mass of the Sun and 3.3[13] times the Sun's radius. It is about 293[12] million years old with a projected rotational velocity of 70 km/s.[17] The star is radiating 133[11] times the Sun's luminosity from its photosphere at an effective temperature of 10,250 K.[13]
Name
In Chinese, {{lang|zh|太微右垣}} ({{lang|zh-Latn|Tài Wēi Yòu Yuán}}), meaning Right Wall of Supreme Palace Enclosure, refers to an asterism consisting of σ Leonis, β Virginis, ι Leonis, θ Leonis and δ Leonis.[2] Consequently, σ Leonis itself is known as {{lang|zh|太微右垣二}} ({{lang|zh-Latn|Tài Wēi Yòu Yuán èr}}, {{lang-en|the Second Star of Right Wall of Supreme Palace Enclosure}}.),[3] representing {{lang|zh|西上將}} ({{lang|zh-Latn|Xīshǎngjiāng}}), meaning The First Western General.[4] 西上將 (Xīshǎngjiāng), spelled Shang Tseang by R.H. Allen, means "the Higher General".[5]
References
1. ^{{cite web | title=sig Leo -- Star | work=SIMBAD | publisher=Centre de Données astronomiques de Strasbourg | url=http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=Sigma+Leonis | accessdate=2010-06-23 }}
2. ^{{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}}.
3. ^{{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/20100819122914/http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_t_z.htm |date=2010-08-19 }}, Hong Kong Space Museum. Accessed on line November 23, 2010.
4. ^{{zh icon}} English-Chinese Glossary of Chinese Star Regions, Asterisms and Star Name {{webarchive|url=https://web.archive.org/web/20080924022136/http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/e_research_chinengstarzone_b.htm |date=2008-09-24 }}, Hong Kong Space Museum. Accessed on line November 23, 2010.
5. ^{{citation | first1=Richard Hinckley | last1=Allen | orig-year=1899 | year=1963 | edition=Dover | title=Star Names, Their Lore and Meaning | chapter=Leo, the Lion | url=http://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Leo*.html | accessdate=2017-08-23 | postscript=. }}
6. ^1 2 {{citation | title=Standardisation of broad band photometry of equatorial standards | journal=South Africa Astronomical Observatory Circular | volume=8 | pages=59–67 | year=1984 | bibcode=1984SAAOC...8...59C | postscript=. | last1=Cousins | first1=A. W. J. }}
7. ^1 {{citation | title=A photometric study of chemically peculiar stars with the STEREO satellites - I. Magnetic chemically peculiar stars | last1=Wraight | first1=K. T. | last2=Fossati | first2=L. | last3=Netopil | first3=M. | last4=Paunzen | first4=E. | last5=Rode-Paunzen | first5=M. | last6=Bewsher | first6=D. | last7=Norton | first7=A. J. | last8=White | first8=Glenn J. | display-authors=1 | postscript=. | journal=Monthly Notices of the Royal Astronomical Society | volume=420 | issue=1 | pages=757–772 | date=February 2012 | doi=10.1111/j.1365-2966.2011.20090.x | bibcode=2012MNRAS.420..757W |arxiv = 1110.6283 }}
8. ^1 2 3 {{citation | title=spectroscopic survey on the multiplicity of high-mass stars | display-authors=1 | last1=Chini | first1=R. | last2=Hoffmeister | first2=V. H. | last3=Nasseri | first3=A. | last4=Stahl | first4=O. | last5=Zinnecker | first5=H. | journal=Monthly Notices of the Royal Astronomical Society | volume=424 | issue=3 | pages=1925–1929 | date=August 2012 | doi=10.1111/j.1365-2966.2012.21317.x | bibcode=2012MNRAS.424.1925C | arxiv=1205.5238}}
9. ^1 2 3 {{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=. }}
10. ^1 2 3 4 {{citation | title=The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets | last1=David | first1=Trevor J. | last2=Hillenbrand | first2=Lynne A. | journal=The Astrophysical Journal | volume=804 | issue=2 | pages=146 | year=2015 | bibcode=2015ApJ...804..146D | doi=10.1088/0004-637X/804/2/146 | arxiv=1501.03154 | postscript=. }}
11. ^1 2 {{cite book | last=Wilson | first=Ralph Elmer | date=1953 | title=General Catalogue of Stellar Radial Velocities | publisher=Carnegie Institution of Washington | location=Washington | bibcode=1953GCRV..C......0W }}
12. ^1 2 {{cite journal | author=Johnson, H. L.| author2=Iriarte, B.| author3=Mitchell, R. I.| author4=Wisniewskj, W. Z. | title=UBVRIJKL photometry of the bright stars | journal=Communications of the Lunar and Planetary Laboratory | volume=4 | issue=99 | date=1966 | bibcode=1966CoLPL...4...99J }}
13. ^1 2 {{cite journal | author=Bernacca, P. L.| author2=Perinotto, M. | title=A catalogue of stellar rotational velocities | journal=Contributi Osservatorio Astronomico di Padova in Asiago | volume=239 | issue=1 | date=1970 | bibcode=1970CoAsi.239....1B }}
14. ^1 2 3 4 5 {{cite journal | author=Lipski, Ł.| author2=Stȩpień, K. | title=Effective temperatures of magnetic chemically peculiar stars from full spectral energy distributions | journal=Monthly Notices of the Royal Astronomical Society | volume=385 | issue=1 | pages=481–492 |date=March 2008 | doi=10.1111/j.1365-2966.2008.12856.x | bibcode=2008MNRAS.385..481L |arxiv = 0712.3664 }}
15. ^1 {{citation | last1=Fitzpatrick | first1=E. L. | last2=Massa | first2=D. | title=Determining the Physical Properties of the B Stars. II. Calibration of Synthetic Photometry | journal=The Astronomical Journal | volume=129 | issue=3 | pages=1642–1662 |date=March 2005 | doi=10.1086/427855 | bibcode=2005AJ....129.1642F |arxiv = astro-ph/0412542 }}