16 Librae

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16 Librae
Observation data
Epoch J2000      Equinox J2000
Constellation Libra
Right ascension 14h 57m 11.00009s[1]
Declination −04° 20′ 47.2547″[1]
Apparent magnitude (V) 4.49[2]
Spectral type F2 V[3]
U−B color index +0.05[2]
B−V color index +0.32[2]
Radial velocity (Rv)+26.3±0.6[4] km/s
Proper motion (μ) RA: −96.98[1] mas/yr
Dec.: −153.40[1] mas/yr
Parallax (π)37.17 ± 0.32[1] mas
Distance87.7 ± 0.8 ly
(26.9 ± 0.2 pc)
Absolute magnitude (MV)2.32[5]
16 Lib A
Mass1.47[6] M
Luminosity9.77[5] L
Surface gravity (log g)3.99[6] cgs
Temperature7,187±244[6] K
Metallicity [Fe/H]−0.13[7] dex
Rotational velocity (v sin i)113.3[8] km/s
Age660[6] Myr
Other designations
16 Lib, BD−03° 3696, FK5 3177, GJ 9503, HD 132052, HIP 73165, HR 5570, SAO 140240, WDS J14572-0421A[9]
Database references

16 Librae is a star in the constellation Libra. It is a faint star but visible to the naked eye with an apparent visual magnitude of 4.49.[2] An annual parallax shift of 37.17[1] mas yields a distance estimate of 87.7 light years. It is moving further from the Sun with a radial velocity of +26 km/s.[4]

This is an ordinary F-type main-sequence star with a stellar classification of F2 V.[3] It is an estimated 660[6] million years old and is spinning rapidly with a projected rotational velocity of 113 km/s.[8] The star has 1.47[6] times the mass of the Sun and is radiating nearly 10[5] times the Sun's luminosity from its photosphere at an effective temperature of about 7,187 K.[6]

16 Librae has a common proper motion companion located at an angular separation of 22.8 arc seconds along a position angle of 297°, as of 1999. Designated component B, this is a red dwarf star with a class of about M6 and an infrared J-band magnitude of 12.19.[10]


  1. ^ a b c d e f van 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.
  2. ^ a b c d Ducati, J. R. (2002), "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system", CDS/ADC Collection of Electronic Catalogues, 2237, Bibcode:2002yCat.2237....0D.
  3. ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H.
  4. ^ a b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, A61.
  5. ^ a b c 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.
  6. ^ a b c d e f g David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146.
  7. ^ Casagrande, L.; et al. (June 2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy and Astrophysics, 530: A138, arXiv:1103.4651, Bibcode:2011A&A...530A.138C, doi:10.1051/0004-6361/201016276.
  8. ^ a b Schröder, C.; et al. (January 2009), "Ca II HK emission in rapidly rotating stars. Evidence for an onset of the solar-type dynamo", Astronomy and Astrophysics, 493 (3): 1099–1107, Bibcode:2009A&A...493.1099S, doi:10.1051/0004-6361:200810377.
  9. ^ "16 Lib". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-01-30.
  10. ^ Scholz, R. -D. (March 2016), "Overlooked wide companions of nearby F stars", Astronomy & Astrophysics, 587: 8, arXiv:1601.01896, Bibcode:2016A&A...587A..51S, doi:10.1051/0004-6361/201527965, A51