HD 185351
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cygnus[1] |
| Right ascension | 19h 36m 37.977s[2] |
| Declination | +44° 41′ 41.76″[2] |
| Apparent magnitude (V) | 5.17[1] |
| Characteristics | |
| Evolutionary stage | Subgiant[3] |
| Spectral type | G8.5IIIb Fe−0.5[4] |
| B−V color index | 0.928±0.001[1] |
| Astrometry | |
| Radial velocity (Rv) | −5.422±0.006[5] km/s |
| Proper motion (μ) | RA: −95.016 mas/yr[2] Dec.: −104.858 mas/yr[2] |
| Parallax (π) | 24.261 ± 0.0573 mas[2] |
| Distance | 134.4 ± 0.3 ly (41.22 ± 0.10 pc) |
| Absolute magnitude (MV) | 2.13[3] |
| Details | |
| Mass | 1.58+0.04 −0.02[6] M☉ |
| Radius | 4.92+0.15 −0.07[6] R☉ |
| Luminosity | 13.8[7] L☉ |
| Surface gravity (log g) | 3.25+0.01 −0.02[6] cgs |
| Temperature | 5,042±32 K[3] K |
| Metallicity [Fe/H] | 0.16[6] dex |
| Rotational velocity (v sin i) | 2.14±0.23[7] km/s |
| Age | 2.32+0.04 −0.07[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 185351 is a star in the constellation of Cygnus, the swan. With an apparent visual magnitude of 5.17,[1] it is faintly visible to the naked eye on a dark night. Based on parallax measurements, HD 185351 is located at a distance of 134 light years from the Sun.[2] It is drifting closer with a heliocentric radial velocity of −5.4 km/s.[5]
This was the third brightest star in the view field of the Kepler space telescope, with only θ Cyg and CH Cyg being brighter. The resulting data was used to measure asteroseismic oscillations that yielded a mass estimate for HD 185351, after incorporating interferometric and spectroscopic observations.[3] The result is consistent with the value of 1.60 M☉ provided by a refined stellar model.[6] In the past, the star was likely an A-type main-sequence star similar to Procyon. Hence, it is sometimes dubbed a "retired A star".[3]
HD 185351 has a stellar classification of G8.5IIIb Fe−0.5,[4] suggesting this is a late G-type giant star with a mild underabundance of iron compared to similar stars. However, its location on the H-R diagram is more consistent with being a less evolved subgiant star.[3] It has expanded to nearly five times the radius of the Sun[6] and is radiating 13.8[7] times the Sun's luminosity. The star has an estimated age of 2.3 billion years[6] and is spinning with a projected rotational velocity of 2 km/s.[7]
As of 2011, searches for planetary companions using Doppler spectroscopy were unsuccessful.[3]
References
[edit]- ^ a b c d 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.
- ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e f g Johnson, John Asher; et al. (October 2014), "The physical parameters of the retired A star HD 185351", The Astrophysical Journal, 794 (1), id. 15, arXiv:1407.2329, Bibcode:2014ApJ...794...15J, doi:10.1088/0004-637X/794/1/15.
- ^ a b Keenan, Philip C.; McNeil, Raymond C (1989), "The Perkins catalog of revised MK types for the cooler stars", The Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373, S2CID 123149047.
- ^ a b Jönsson, Henrik; et al. (August 17, 2020), "APOGEE Data and Spectral Analysis from SDSS Data Release 16: Seven Years of Observations Including First Results from APOGEE-South", The Astronomical Journal, 160 (3), American Astronomical Society: 120, arXiv:2007.05537, Bibcode:2020AJ....160..120J, doi:10.3847/1538-3881/aba592, ISSN 0004-6256.
- ^ a b c d e f g h Hjørringgaard, J. G.; et al. (January 2017), "Testing stellar evolution models with the retired A star HD 185351", Monthly Notices of the Royal Astronomical Society, 464 (3): 3713–3719, arXiv:1610.05990, Bibcode:2017MNRAS.464.3713H, doi:10.1093/mnras/stw2559.
- ^ a b c d Jofré, E.; et al. (2015), "Stellar parameters and chemical abundances of 223 evolved stars with and without planets", Astronomy & Astrophysics, 574: A50, arXiv:1410.6422, Bibcode:2015A&A...574A..50J, doi:10.1051/0004-6361/201424474, S2CID 53666931.
- ^ "HD 185351", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2025-01-30.