49 Librae

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49 Librae
Observation data
Epoch J2000      Equinox J2000
Constellation Libra
Right ascension 16h 00m 19.59408s[1]
Declination –16° 32′ 00.2207″[1]
Apparent magnitude (V) 5.47[2]
Characteristics
Spectral type F7 V[3]
U−B color index +0.03[2]
B−V color index +0.52[2]
Astrometry
Radial velocity (Rv) –20.1 ± 4.0[4] km/s
Proper motion (μ) RA: –631.32[1] mas/yr
Dec.: –417.38[1] mas/yr
Parallax (π) 28.40 ± 1.23[1] mas
Distance 115 ± 5 ly
(35 ± 2 pc)
Absolute magnitude (MV) 2.89[4]
Details
Surface gravity (log g) 4.14[5] cgs
Temperature 6,237[4] K
Metallicity [Fe/H] –0.02[4] dex
Rotational velocity (v sin i) 10[4] km/s
Age 2.5[4] Gyr
Other designations
49 Lib, BD–16 4196, FK5 1419, GJ 3931, HD 143333, HIP 78400, HR 5954, SAO 159625.[6]

49 Librae is the Flamsteed designation for a spectroscopic binary[7] star system in the Zodiac constellation of Libra. It has an apparent visual magnitude of 5.47,[2] making it faintly visible to the naked eye from dark suburban skies. Measurements made with the Hipparcos spacecraft show an annual parallax shift of 0.02840″,[1] which is equivalent to a distance of roughly 115 ly (35 pc) from the Sun.

The combined spectrum of 49 Librae matches a stellar classification of F7 V,[3] with the luminosity class of V suggesting the primary forms a main sequence star like the Sun.

References[edit]

  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 Nicolet, B. (October 1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series 34: 1–49, Bibcode:1978A&AS...34....1N. 
  3. ^ a b Gray, R. O. et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637. 
  4. ^ a b c d e f Nordström, B. et al. (November 2007), "The Geneva-Copenhagen survey of the Solar neighbourhood. II. New uvby calibrations and rediscussion of stellar ages, the G dwarf problem, age-metallicity diagram, and heating mechanisms of the disk", Astronomy & Astrophysics 475 (2): 519–537, arXiv:0707.1891, Bibcode:2007A&A...475..519H, doi:10.1051/0004-6361:20077221. 
  5. ^ Balachandran, Suchitra (May 1, 1990), "Lithium depletion and rotation in main-sequence stars", Astrophysical Journal, Part 1 354: 310–332, Bibcode:1990ApJ...354..310B, doi:10.1086/168691. 
  6. ^ "49 Lib -- Star", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), retrieved 2013-11-06. 
  7. ^ Abt, Helmut A. (January 2009), "MK Classifications of Spectroscopic Binaries", The Astrophysical Journal Supplement 180 (1): 117–118, Bibcode:2009ApJS..180..117A, doi:10.1088/0067-0049/180/1/117. 

Coordinates: Sky map 16h 00m 19.594s, −16° 32′ 00.22″