HD 90264
HD 90264 is a binary star[4] system in the southern constellation of Carina. It has the Bayer designation of L Carinae, while HD 90264 is the star's identifier in the Henry Draper catalogue. This system has a blue-white hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.97.[2] It is located at a distance of approximately 402 light years from the Sun based on parallax, and is drifting further away with a radial velocity of around +12 km/s.[2] The system is a member of the Lower Centaurus Crux association of the Sco-Cen Complex.[4]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Carina |
| Right ascension | 10h 22m 58.14606s[1] |
| Declination | −66° 54′ 05.3903″[1] |
| Apparent magnitude (V) | 4.97[2] |
| Characteristics | |
| Spectral type | B8V[3] |
| B−V color index | −0.128±0.003[2] |
| Astrometry | |
| Radial velocity (Rv) | +12.0±4.2[2] km/s |
| Proper motion (μ) | RA: −22.39[1] mas/yr Dec.: +11.48[1] mas/yr |
| Parallax (π) | 8.12 ± 0.18 mas[1] |
| Distance | 402 ± 9 ly (123 ± 3 pc) |
| Absolute magnitude (MV) | −0.403[4] |
| Orbit[4] | |
| Period (P) | 15.727±0.001 d |
| Semi-major axis (a) | 52.66 R☉ |
| Eccentricity (e) | 0.044±0.014 |
| Inclination (i) | 54° |
| Periastron epoch (T) | 2,452,814.78±1.05 JD |
| Argument of periastron (ω) (secondary) | 138±25° |
| Semi-amplitude (K1) (primary) | 62.2±1.9 km/s |
| Semi-amplitude (K2) (secondary) | 76.0±1.5 km/s |
| Details | |
| A | |
| Mass | 4.3[4] M☉ |
| Luminosity | 288.39[2] L☉ |
| Rotational velocity (v sin i) | 7[4] km/s |
| Age | 18[4] Myr |
| B | |
| Mass | 3.5[4] M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
This system was found to be a close double-lined spectroscopic binary in 1977, consisting of two B-type main-sequence stars. It has a near circular orbit with a period of 15.727 days and a semimajor axis of 0.2449 AU. They appear to be spin-orbit synchronized. Both stars appear to be deficient in helium. The primary is a helium variable star while the companion is a mercury-manganese star. The variability of both stars aligns favorably with the orbital period.[4]
References edit
- ^ a b c d e 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:10.1051/0004-6361:20078357.
- ^ a b c d e f 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.
- ^ Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
- ^ a b c d e f g h i Quiroga, C.; et al. (October 2010), "The chemically peculiar double-lined spectroscopic binary HD 90264", Astronomy and Astrophysics, 521: 7, Bibcode:2010A&A...521A..75Q, doi:10.1051/0004-6361/201014521, A75.
- ^ "HD 90264". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-26.