Theta Librae

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Theta Librae
Diagram showing star positions and boundaries of the Libra constellation and its surroundings
Cercle rouge 100%.svg

Location of θ Librae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Libra
Right ascension 15h 53m 49.5381s[1]
Declination –16° 43′ 45.457″[1]
Apparent magnitude (V) 4.136
Characteristics
Spectral type K0 III[2]
U−B color index +0.82[3]
B−V color index +1.01[3]
Astrometry
Radial velocity (Rv) 3.4[4] km/s
Proper motion (μ) RA: +100.12[1] mas/yr
Dec.: +135.27[1] mas/yr
Parallax (π) 20.02 ± 0.88[1] mas
Distance 163 ± 7 ly
(50 ± 2 pc)
Details
Mass 1.84[5] M
Luminosity 35[6] L
Surface gravity (log g) 2.99[7] cgs
Temperature 4,700[7] K
Metallicity [Fe/H] –0.08[7] dex
Rotational velocity (v sin i) 10[8] km/s
Other designations
46 Librae, HR 5908, BD−16 4174, HD 142198, GCTP, SAO 159563, HIP 77853.[2]

Theta Librae is a giant star in the southern zodiac constellation of Libra. It is located about 163 light-years (50 parsecs) from the Earth and has an estimated mass about 84% greater than the Sun. This star is radiating about 35[6] times the luminosity of the Sun from its outer atmosphere at an effective temperature of about 4,700 K.[7]

References[edit]

  1. ^ a b c d e Perryman, M. A. C.; et al. (April 1997). "The HIPPARCOS Catalogue". Astronomy & Astrophysics 323: L49–L52. Bibcode:1997A&A...323L..49P. 
  2. ^ a b "tet Lib -- Star". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2011-01-24. 
  3. ^ a b Johnson, H. L.; Iriarte, B.; Mitchell, R. I.; Wisniewskj, W. Z. (1966). "UBVRIJKL photometry of the bright stars". Communications of the Lunar and Planetary Laboratory 4 (99). Bibcode:1966CoLPL...4...99J. 
  4. ^ Wilson, Ralph Elmer (1953). General Catalogue of Stellar Radial Velocities. Washington: Carnegie Institution of Washington. Bibcode:1953QB901.W495..... 
  5. ^ Liu, Y. J.; Zhao, G.; Shi, J. R.; Pietrzyński, G.; Gieren, W. (December 2007). "The abundances of nearby red clump giants". Monthly Notices of the Royal Astronomical Society 382 (2): 553–566. Bibcode:2007MNRAS.382..553L. doi:10.1111/j.1365-2966.2007.11852.x.  See online data.
  6. ^ a b Mallik, Sushma V. (December 1999), "Lithium abundance and mass", Astronomy and Astrophysics 352: 495–507, Bibcode:1999A&A...352..495M 
  7. ^ a b c d Mallik, Sushma V. (October 1998). "Chromospheric activity in cool stars and the lithium abundance". Astronomy and Astrophysics 338: 623–636. Bibcode:1998A&A...338..623M. 
  8. ^ Bernacca, P. L.; Perinotto, M. (1970). "A catalogue of stellar rotational velocities". Contributi Osservatorio Astronomico di Padova in Asiago 239 (1). Bibcode:1970CoAsi.239....1B.