HD 178233 is a single[9] star in the northern constellation of Lyra. It is bright enough to be dimly visible to the naked eye with an apparent visual magnitude of 5.53,[2] making it a sixth magnitude star. The distance to HD 178233 is 134 light years based on parallax measurements, but it is drifting closer to the Sun with a radial velocity of approximately −24 km/s.[5]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Lyra |
| Right ascension | 19h 06m 37.7345s[1] |
| Declination | +28° 37′ 42.941″[1] |
| Apparent magnitude (V) | 5.53[2] |
| Characteristics | |
| Spectral type | F0III[3] or A7V[4] |
| U−B color index | +0.04 |
| B−V color index | 0.296±0.003[2] |
| Astrometry | |
| Radial velocity (Rv) | −24.0±4.3[5] km/s |
| Proper motion (μ) | RA: 75.662[1] mas/yr Dec.: 85.291[1] mas/yr |
| Parallax (π) | 24.3974 ± 0.0867 mas[1] |
| Distance | 133.7 ± 0.5 ly (41.0 ± 0.1 pc) |
| Absolute magnitude (MV) | 2.52[2] |
| Details | |
| Mass | 1.54[6] M☉ |
| Radius | 1.83+0.10 −0.06[1] R☉ |
| Luminosity | 8.233±0.038[1] L☉ |
| Surface gravity (log g) | 4.21±0.14[6] cgs |
| Temperature | 7,220+126 −175[1] K |
| Metallicity [Fe/H] | 0.04[7] dex |
| Age | 498[6] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The stellar classification of this star was determined to be F0III by A. Cowley and associates (1969),[3] matching an evolved F-type giant star. In contrast, D. R. Palmer and associates (1968) listed it as an A-type main-sequence star with a class of A7V.[4] It is about a half billion years old and is spinning rapidly with a projected rotational velocity of 165.0 km/s, which is giving the star an equatorial bulge that is ~24% wider than the polar radius.[10] The star has 1.5[6] times the mass and 1.8[1] times the mean radius of the Sun. It is radiating over eight times the luminosity of the Sun from its photosphere at an effective temperature of 7,220 K.[1]
References
edit- ^ a b c d e f g h i j 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. Gaia DR2 record for this source at VizieR.
- ^ 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 Cowley, A.; et al. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal. 74: 375–406. Bibcode:1969AJ.....74..375C. doi:10.1086/110819.
- ^ a b Palmer, D. R.; et al. (1968). "The radial velocities spectral types and projected rotational velocities of 633 bright northern A stars". Royal Observatory Bulletin. 135: 385. Bibcode:1968RGOB..135..385P.
- ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
- ^ a b c d David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. S2CID 33401607.
- ^ Netopil, Martin (August 2017). "Metallicity calibrations for dwarf stars and giants in the Geneva photometric system". Monthly Notices of the Royal Astronomical Society. 469 (3): 3042–3055. arXiv:1705.00883. Bibcode:2017MNRAS.469.3042N. doi:10.1093/mnras/stx1077. S2CID 119034918.
- ^ "HD 178233". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-10-11.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID 14878976.
- ^ Van Belle, Gerard T. (2012). "Interferometric observations of rapidly rotating stars". The Astronomy and Astrophysics Review. 20 (1): 51. arXiv:1204.2572. Bibcode:2012A&ARv..20...51V. doi:10.1007/s00159-012-0051-2. S2CID 119273474.