Zeta Leonis (ζ Leonis, abbreviatedZeta Leo,ζ Leo), also namedAdhafera/ædəˈfɪərə/,[12] is a third-magnitudestar in theconstellation ofLeo, the lion. It forms the second star (afterGamma Leonis) in the blade ofthe sickle, which is anasterism formed from the head of Leo.[13]
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Leo |
| Right ascension | 10h 16m 41.41597s[1] |
| Declination | +23° 25′ 02.3221″[1] |
| Apparent magnitude (V) | 3.33[2] |
| Characteristics | |
| Spectral type | F0 III[3][4] |
| U−Bcolor index | +0.07[2] |
| B−Vcolor index | +0.30[2] |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | −15.6[5] km/s |
| Proper motion (μ) | RA: +18.39[1]mas/yr Dec.: −6.84[1]mas/yr |
| Parallax (π) | 11.90±0.18 mas[1] |
| Distance | 274 ± 4 ly (84 ± 1 pc) |
| Absolute magnitude (MV) | −1.19[6] |
| Details | |
| Mass | 3[7] M☉ |
| Radius | 10.5[8] R☉ |
| Luminosity | 223[8] L☉ |
| Surface gravity (log g) | 3.0[9] cgs |
| Temperature | 6,900[8] K |
| Metallicity [Fe/H] | −0.03[10] dex |
| Rotational velocity (v sin i) | 72.4[9] km/s |
| Other designations | |
| Adhafera, Aldhafera, Adhafara,ζ Leo,36 Leo,BD+24°2209,FK5 384,HD 89025,HIP 50335,HR 4031,SAO 81265,GC 14107,NSV 04804,WDS 10167+2325A[11] | |
| Database references | |
| SIMBAD | data |
Nomenclature
editζ Leonis (Latinised toZeta Leonis) is the star'sBayer designation. It has the traditional nameAdhafera (Aldhafera,Adhafara), which comes from theArabicالضفيرةaḍ-ḍafīrah 'the braid/curl', a reference to its position in the lion's mane.[citation needed] In 2016, theInternational Astronomical Union organized aWorking Group on Star Names (WGSN)[14] to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016[15] included a table of the first two batches of names approved by the WGSN; which includedAdhafera for this star.
Properties
editAdhafera is agiant star with astellar classification of F0 III. Since 1943, thespectrum of this star has served as one of the stable anchor points by which other stars are classified.[4] Itsapparent magnitude is +3.44, making it relatively faint for a star that is visible to the naked eye. Nevertheless, it shines with 220 times theluminosity of the Sun.[9] Adhafera has about three times the Sun's mass[7] and 10.5 times the radius of the Sun.[8]Parallax measurements from theHipparcos satellite yield an estimated distance to Adhafera of 274light-years (84parsecs)[1] from theSun.
Adhafera forms adouble star with an optical companion that has an apparent magnitude of 5.90. Known as35 Leonis, this star is separated from Adhafera by 325.9 arcseconds along aposition angle of 340°.[16][17] The two stars do not form abinary star system as 35 Leo is only 100light years from Earth, thus separating the two stars by approximately 174light-years (53parsecs).
References
edit- ^abcdefvan Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction",Astronomy and Astrophysics,474 (2):653–664,arXiv:0708.1752,Bibcode:2007A&A...474..653V,doi:10.1051/0004-6361:20078357,S2CID 18759600
- ^abcFernie, J. D. (May 1983), "New UBVRI photometry for 900 supergiants",Astrophysical Journal Supplement Series,52:7–22,Bibcode:1983ApJS...52....7F,doi:10.1086/190856
- ^Montes, D.; et al. (November 2001), "Late-type members of young stellar kinematic groups - I. Single stars",Monthly Notices of the Royal Astronomical Society,328 (1):45–63,arXiv:astro-ph/0106537,Bibcode:2001MNRAS.328...45M,doi:10.1046/j.1365-8711.2001.04781.x,S2CID 55727428
- ^abGarrison, R. F. (December 1993),"Anchor Points for the MK System of Spectral Classification",Bulletin of the American Astronomical Society,25: 1319,Bibcode:1993AAS...183.1710G, archived fromthe original on 2019-06-25, retrieved2012-02-04
- ^Wielen, R.; et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions",Veroeffentlichungen des Astronomischen Rechen-Instituts Heidelberg,35 (35), Astronomisches Rechen-Institut Heidelberg: 1,Bibcode:1999VeARI..35....1W
- ^Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation",Astronomy Letters,38 (5): 331,arXiv:1108.4971,Bibcode:2012AstL...38..331A,doi:10.1134/S1063773712050015,S2CID 119257644.
- ^abKaler, James B.,"ADHAFERA (Zeta Leonis)",Stars, University of Illinois, retrieved2010-05-12
- ^abcdMcDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017-10-01), "Fundamental parameters and infrared excesses of Tycho-Gaia stars",Monthly Notices of the Royal Astronomical Society,471 (1):770–791,arXiv:1706.02208,doi:10.1093/mnras/stx1433,ISSN 0035-8711Zeta Leonis' database entry atVizieR.
- ^abcMassarotti, Alessandro; et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity",The Astronomical Journal,135 (1):209–231,Bibcode:2008AJ....135..209M,doi:10.1088/0004-6256/135/1/209,S2CID 121883397
- ^Gray, R. O.; Graham, P. W.; Hoyt, S. R. (April 2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. II. Basic Parameters of Program Stars and the Role of Microturbulence",The Astronomical Journal,121 (4):2159–2172,Bibcode:2001AJ....121.2159G,doi:10.1086/319957
- ^"zet Leo -- Variable Star",SIMBAD, Centre de Données astronomiques de Strasbourg, retrieved2010-05-12
- ^"List of IAU-approved Star Names". Retrieved24 January 2022.
- ^Proctor, Mary (July 1896),"Evenings with the Stars",Popular Astronomy,4: 565
- ^"IAU Working Group on Star Names (WGSN)". Retrieved22 May 2016.
- ^"Bulletin of the IAU Working Group on Star Names, No. 1"(PDF). Retrieved28 July 2016.
- ^"CCDM (Catalog of Components of Double & Multiple stars (Dommanget+ 2002)",VizieR,Centre de Données astronomiques de Strasbourg, retrieved2010-05-12
- ^Adhafera, Alcyone Bright Star Catalogue, retrieved2010-05-12