HD 196761

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HD 196761
Observation data
Epoch J2000      Equinox J2000
Constellation Capricornus
Right ascension 20h 40m 11.7558s[1]
Declination −23° 46′ 25.923″[1]
Apparent magnitude (V) 6.37[2]
Characteristics
Spectral type G8V[3]
U−B color index 1.393[4]
B−V color index 0.719[5]
Astrometry
Radial velocity (Rv) –45.3[6] km/s
Proper motion (μ) RA: 501.45[5] mas/yr
Dec.: 461.36[5] mas/yr
Parallax (π) 69.53 ± 0.40[5] mas
Distance 46.9 ± 0.3 ly
(14.38 ± 0.08 pc)
Absolute magnitude (MV) 5.58[7]
Details
Radius 0.88[8] R
Surface gravity (log g) 4.54[3] cgs
Temperature 5,457[7] K
Metallicity \begin{smallmatrix}\left[\frac{Fe}{H}\right]\ =\ -0.30\end{smallmatrix}[7]
Other designations
GJ 796, HR 7898, CD-24 16193, HD 196761, LTT 8172, SAO 189549, HIP 101997.[2]

HD 196761 is a main-sequence dwarf star in the constellation Capricornus and is located about 47 light years from the Solar System. It has a stellar classification of G8V and is about 88% of the radius of the Sun.[8] Compared to the Sun, this star has about half the proportion of elements other than hydrogen and helium.[7][9]

The space velocity components of this star are U = −59, V = 20 and W = 4 km/s. It is following an orbit through the Milky Way that has an eccentricity of 0.18, bringing it as close as 24.27 kly (7.44 kpc) and as distant as 34.6 kly (10.6 kpc) from the Galactic Center. The inclination of this orbit will carry HD 196761 no more than 0.65 kly (0.20 kpc) from the plane of the galactic disk.[7]

References[edit]

  1. ^ a b Perryman, M. A. C. et al. (1997), "The Hipparcos Catalogue", Astronomy & Astrophysics 323: L49–L52, Bibcode:1997A&A...323L..49P 
  2. ^ a b "LHS 3570 -- High proper-motion Star". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2010-02-20. 
  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. ^ Rufener, F. (October 1976). "Second catalogue of stars measured in the Geneva Observatory photometric system". Astronomy & Astrophysics, Supplement Series 26: 275−351. Bibcode:1976A&AS...26..275R. 
  5. ^ a b c d van Leeuwen, Floor (2007). Hipparcos, the new Reduction of the Raw data. Astrophysics and Space Science Library 474. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. ISBN 978-1-4020-6341-1. 
  6. ^ Evans, D. S. (June 20–24, 1966). "The Revision of the General Catalogue of Radial Velocities". In Batten, Alan Henry; Heard, John Frederick. Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30. University of Toronto: International Astronomical Union. Retrieved 2009-09-10. 
  7. ^ a b c d e Holmberg, J.; Nordström, B.; Andersen, J. (July 2009). "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics". Astronomy and Astrophysics, Supplement Series 501 (3): 941−947. arXiv:0811.3982. Bibcode:2009A&A...501..941H. doi:10.1051/0004-6361/200811191. 
  8. ^ a b Johnson, H. M.; Wright, C. D. (1983). "Predicted infrared brightness of stars within 25 parsecs of the Sun". Astrophysical Journal, Supplement Series 53: 643−711. Bibcode:1983ApJS...53..643J. doi:10.1086/190905. 
  9. ^ The metallicity of the star is −0.30, so the proportion of metals is given by:
    10−0.30 = 0.501
    or 50%.