Article · Wikipedia archive · Last revised Jun 18, 2026

16 Librae

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. An annual parallax shift of 37.17 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.

Last revised
Jun 18, 2026
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16 Librae
Location of 16 Librae (circled in red)
Observation data
Epoch J2000      Equinox J2000
Constellation Libra
Right ascension 14h 57m 11.00009s1
Declination −04° 20′ 47.2547″1
Apparent magnitude (V) 4.492
Characteristics
Spectral type F2 V3
U−B color index +0.052
B−V color index +0.322
Astrometry
Radial velocity (Rv)+26.3±0.64 km/s
Proper motion (μ) RA: −96.981 mas/yr
Dec.: −153.401 mas/yr
Parallax (π)37.17±0.32 mas1
Distance87.7 ± 0.8 ly
(26.9 ± 0.2 pc)
Absolute magnitude (MV)2.325
Details
16 Lib A
Mass1.476 M☉
Luminosity9.775 L☉
Surface gravity (log g)3.996 cgs
Temperature7,187±2446 K
Metallicity [Fe/H]−0.137 dex
Rotational velocity (v sin i)113.38 km/s
Age6606 Myr
Other designations
16 Lib, BD−03°3696, FK5 3177, GJ 9503, HD 132052, HIP 73165, HR 5570, SAO 140240, WDS J14572-0421A9
Database references
SIMBADdata

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 37.171 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 6606 million years old and is spinning rapidly with a projected rotational velocity of 113 km/s.8 The star has 1.476 times the mass of the Sun and is radiating nearly 105 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

References

References

  1. 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, S2CID 18759600.
  2. 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. 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. 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, S2CID 59451347, A61.
  5. 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.
  6. 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, S2CID 33401607.
  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, S2CID 56118016.
  8. Schröder, C.; Reiners, Ansgar; Schmitt, Jürgen H. M. M. (January 2009), "Ca II HK emission in rapidly rotating stars. Evidence for an onset of the solar-type dynamo" (PDF), Astronomy and Astrophysics, 493 (3): 1099–1107, Bibcode:2009A&A...493.1099S, doi:10.1051/0004-6361:200810377, archived from the original (PDF) on 2017-09-22, retrieved 2018-11-04
  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, S2CID 118348424, A51