HD 157819

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HD 157819
Observation data
Epoch J2000      Equinox J2000
Constellation Ara
Right ascension 17h 28m 38.91416s[1]
Declination –55° 10′ 10.8720″[1]
Apparent magnitude (V) 5.94[2]
Characteristics
Spectral type G8 II-III[3]
B−V color index +1.11[2]
Astrometry
Radial velocity (Rv) –12.6 ± 0.4[4] km/s
Proper motion (μ) RA: +2.52[1] mas/yr
Dec.: -8.92[1] mas/yr
Parallax (π) 3.31 ± 0.41[1] mas
Distance approx. 1,000 ly
(approx. 300 pc)
Absolute magnitude (MV) –2.9[5]
Other designations
HD 157819, HIP 85520, HR 6487, SAO 244770.[6]

HD 157819 is the Henry Draper Catalogue designation for a star in the southern constellation of Ara. It is faintly visible to the naked eye at an apparent visual magnitude of 5.94[2] and is approximately 1,000 light-years (310 parsecs) distant from the Earth.[1] The spectrum of this star fits a stellar classification of G8 II-III,[3] indicating it is a G-type star that is somewhere between the giant and bright giant stages of its evolution.

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 Corben, P. M.; Stoy, R. H. (1968), "Photoelectric Magnitudes and Colours for Bright Southern Stars", Monthly Notes of the Astronomical Society of Southern Africa 27: 11, Bibcode:1968MNSSA..27...11C. 
  3. ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H. 
  4. ^ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system", Astronomy Letters 32 (11): 759–771, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065. 
  5. ^ Eggen, O. J. (August 1983), "The reddening, metal abundance, and luminosity of high-luminosity G-type stars", Astronomical Journal 88: 1187–1198, Bibcode:1983AJ.....88.1187E, doi:10.1086/113409. 
  6. ^ "HR 6487 -- Star in double system", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), retrieved 2012-08-04. 

External links[edit]