HD 77912 is a single[8] star in the northern constellation of Lynx. It is visible to the naked eye with an apparent visual magnitude of 4.56.[2] The star is located 650 light years from the Sun, as determined from its annual parallax shift of 5.0 mas.[1] It is moving further away with a heliocentric radial velocity of +16.6 km/s.[4] HD 77912 has a peculiar velocity of 23.1+2.9
−1.1 km/s, which may mark it as a runaway star.[9]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lynx |
| Right ascension | 09h 06m 31.76860s[1] |
| Declination | +38° 27′ 07.9756″[1] |
| Apparent magnitude (V) | 4.56[2] |
| Characteristics | |
| Spectral type | G7 II Ba0.2[3] |
| B−V color index | 1.037±0.003[4] |
| Astrometry | |
| Radial velocity (Rv) | +16.6±0.2[4] km/s |
| Proper motion (μ) | RA: −27.653[1] mas/yr Dec.: −15.055[1] mas/yr |
| Parallax (π) | 5.0045 ± 0.1977 mas[1] |
| Distance | 650 ± 30 ly (200 ± 8 pc) |
| Absolute magnitude (MV) | −1.46±0.093[5] |
| Details | |
| Mass | 4.60[6] M☉ |
| Radius | 33±5[2] R☉ |
| Luminosity | 1,168.35[4] L☉ |
| Surface gravity (log g) | 1.75[6] cgs |
| Temperature | 4,899[6] K |
| Metallicity [Fe/H] | −0.14[6] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
The stellar classification of HD 77912 is G7 II Ba0.2,[3] indicating it is a bright giant with a mild overabundance of barium. It has 4.6[6] times the mass of the Sun and has expanded to 33[2] times the Sun's radius. The star is radiating 1,168[4] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,899 K.[6]
References
edit- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051.
- ^ a b c d Van Belle, G. T.; et al. (2009), "Supergiant temperatures and linear radii from near-infrared interferometry", Monthly Notices of the Royal Astronomical Society, 394 (4): 1925, arXiv:0811.4239, Bibcode:2009MNRAS.394.1925V, doi:10.1111/j.1365-2966.2008.14146.x, S2CID 118372600.
- ^ a b Lu, Phillip K. (1991), "Taxonomy of barium stars", Astronomical Journal, 101: 2229, Bibcode:1991AJ....101.2229L, doi:10.1086/115845.
- ^ a b c d e 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.
- ^ Park, Sunkyung; et al. (2013), "Wilson-Bappu Effect: Extended to Surface Gravity", The Astronomical Journal, 146 (4): 73, arXiv:1307.0592, Bibcode:2013AJ....146...73P, doi:10.1088/0004-6256/146/4/73, S2CID 119187733.
- ^ a b c d e f Liu, Y. J.; et al. (April 2014), "The Lithium Abundances of a Large Sample of Red Giants", The Astrophysical Journal, 785 (2): 12, arXiv:1404.1687, Bibcode:2014ApJ...785...94L, doi:10.1088/0004-637X/785/2/94, S2CID 119226316, 94.
- ^ "HD 77912". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-30.
- ^ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.