Astronomy:HD 90264

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Short description: Binary star in the constellation Carina
HD 90264
Observation data
Equinox J2000.0]] (ICRS)
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[1] mas
Distance402 ± 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
Mass4.3[4] M
Luminosity288.39[2] L
Rotational velocity (v sin i)7[4] km/s
Age18[4] Myr
B
Mass3.5[4] M
Other designations
L Car, CPD−66°1243, FK5 2834, GC 14283, HD 90264, HIP 50847, HR 4089, SAO 250940[5]
Database references
SIMBADdata

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]

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 astronomical unit|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

  1. 1.0 1.1 1.2 1.3 1.4 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  3. Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode1978mcts.book.....H. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 Quiroga, C. et al. (October 2010), "The chemically peculiar double-lined spectroscopic binary HD 90264", Astronomy and Astrophysics 521: 7, doi:10.1051/0004-6361/201014521, A75, Bibcode2010A&A...521A..75Q. 
  5. "HD 90264". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+90264.