58 Leonis
Observation data
Epoch J2000      Equinox J2000
Constellation Leo
Right ascension 11h 00m 33.64811s[1]
Declination +03° 37′ 02.9766″[1]
Apparent magnitude (V) 4.852[2]
Characteristics
Spectral type K0.5 III Fe-0.5[3]
B−V color index 1.163[2]
Astrometry
Radial velocity (Rv)+5.98[2] km/s
Proper motion (μ) RA: +14.82[1] mas/yr
Dec.: −16.51[1] mas/yr
Parallax (π)9.05 ± 0.20 mas[1]
Distance360 ± 8 ly
(110 ± 2 pc)
Absolute magnitude (MV)−1.04[4]
Details
Mass1.89[2] M☉
Luminosity182[2] L☉
Surface gravity (log g)1.8[4] cgs
Temperature4,519±52[2] K
Metallicity [Fe/H]−0.16±0.10[4] dex
Age1.69[2] Gyr
Other designations
58 Leo, BD+04° 2407, FK5 1284, HD 95345, HIP 53807, HR 4291, SAO 118610, CCDM J11006+0337AB[5]
Database references
SIMBADdata

58 Leonis is a possible binary star[6] system in the southern part of the constellation of Leo, near the border with Sextans. It shines with an apparent magnitude of 4.85,[2] making it bright enough to be seen with the naked eye. An annual parallax shift of 9.05±0.20 mas yields a distance estimate of 360 light years. It is moving further from the Sun with a heliocentric radial velocity of +6 km/s.[2]

This orange hued star is an evolved K-type giant with a stellar classification of K0.5 III Fe-0.5,[3] indicating a mild underabundance of iron in its spectrum. It was identified as a barium star by P. M. Williams (1971).[7] These are theorized to be stars that show an enrichment of s-process elements by mass transfer from a now-white dwarf companion when it passed through the asymptotic giant branch stage.[8] MacConnell et al. (1972) classified 58 Leonis as a marginal barium star.[4] De Castro et al. (2016) consider this to be only a probable barium star, because of the low degree of s-process enrichment, and they rejected it from their sample. Rather than having an evolved companion, it may instead have formed from a cloud that was mildly enriched with s-process elements.[4]

References

  1. 1 2 3 4 5 van Leeuwen, F. (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.
  2. 1 2 3 4 5 6 7 8 9 Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal, 150 (3), 88, arXiv:1507.01466, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, S2CID 118505114.
  3. 1 2 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373, S2CID 123149047.
  4. 1 2 3 4 5 De Castro, D. B.; et al. (2016), "Chemical abundances and kinematics of barium stars", Monthly Notices of the Royal Astronomical Society, 459 (4): 4299, arXiv:1604.03031, Bibcode:2016MNRAS.459.4299D, doi:10.1093/mnras/stw815
  5. ↑ "58 Leo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-03-01.
  6. ↑ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  7. ↑ Williams, P. M. (February 1971), "Abundances in five newly-discovered BA II stars", The Observatory, 91: 37–39, Bibcode:1971Obs....91...37W.
  8. ↑ Bergeat, J.; Knapik, A. (May 1997), "The barium stars in the Hertzsprung-Russel diagram.", Astronomy and Astrophysics, 321: L9, Bibcode:1997A&A...321L...9B.
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