HD 225218
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda | 
| Right ascension | 00h 04m 36.58707s[1] | 
| Declination | +42° 05′ 33.1118″[1] | 
| Apparent magnitude (V) | 6.133 (6.16 + 9.65)[2] | 
| Characteristics | |
| Spectral type | B9III[3] + F0V: | 
| U−B color index | 0.14 | 
| B−V color index | 0.15 | 
| Astrometry | |
| Radial velocity (Rv) | −8.0[4] km/s | 
| Proper motion (μ) | RA: −11.35±0.42[1] mas/yr Dec.: −12.64±0.36[1] mas/yr | 
| Parallax (π) | 2.59 ± 0.56[1] mas | 
| Distance | approx. 1,300 ly (approx. 390 pc) | 
| Orbit[5] | |
| Period (P) | 70.12 yr | 
| Semi-major axis (a) | 0.165" | 
| Eccentricity (e) | 0.515 | 
| Details | |
| Luminosity | 394[6] L☉ | 
| Temperature | 7,611[6] K | 
| Rotation | 25[7] | 
| Other designations | |
| Database references | |
| SIMBAD | data | 
| Database references | |
| SIMBAD | data | 
HD 225218 is a quadruple star system in the northern constellation of Andromeda. The primary component, HD 225218 A, is a giant star with a stellar classification of B9III,[3] an apparent magnitude of 6.16,[2] and is a candidate Lambda Boötis star.[8] It has a fainter, magnitude 9.65 companion, HD 225218 B, at an angular separation of 5.2″ along a position angle of 171°.[2] The primary itself has been identified as a binary star system through interferometry, with the two components separated by 0.165″. The pair, HD 225218 Aa and Ab, orbit each other with a period of about 70 years and an eccentricity of 0.515.[5] Component B is likewise a spectroscopic binary.[8]
References
- 1 2 3 4 5  van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752 , Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357Vizier catalog entry , Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357Vizier catalog entry
- 1 2 3 Mason, Brian D.; et al. (December 2001), "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog", The Astronomical Journal, 122 (6): 3466−3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920
- 1 2 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
- ↑ Wilson, R. E. (1953), General Catalogue of Stellar Radial Velocities, Carnegie Institute of Washington, D.C., Bibcode:1953GCRV..C......0W
- 1 2 Malkov, O. Yu.; et al. (2012), "Dynamical Masses of a Selected Sample of Orbital Binaries", Astronomy & Astrophysics, 546: 5, Bibcode:2012A&A...546A..69M, doi:10.1051/0004-6361/201219774, A69
- 1 2  McDonald, I.;  et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037 , Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x , Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x
- ↑ Abt, Helmut A.; et al. (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal, 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590
- 1 2  Faraggiana, Rosanna; Bonifacio, Piercarlo (September 1999), "How many lambda Bootis stars are binaries?", Astronomy and Astrophysics, 349: 521−531, arXiv:astro-ph/9906009 , Bibcode:1999A&A...349..521F , Bibcode:1999A&A...349..521F
External links
This article is issued from Wikipedia - version of the 4/20/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.