Astronomy:Lambda Normae

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Short description: Star in the constellation Norma
Lambda Normae
Observation data
Equinox J2000.0]] (ICRS)
Constellation Norma
Right ascension  16h 19m 17.64660s[1]
Declination −42° 40′ 26.3014″[1]
Apparent magnitude (V) 5.44[2] (5.83 + 6.86)[3]
Characteristics
Spectral type A0V + A3V
B−V color index 0.099±0.004[2]
Astrometry
Radial velocity (Rv)−15.0±3.7[2] km/s
Proper motion (μ) RA: +7.59[1] mas/yr
Dec.: −13.30[1] mas/yr
Parallax (π)9.35 ± 0.76[1] mas
Distance350 ± 30 ly
(107 ± 9 pc)
Absolute magnitude (MV)0.31[2]
Orbit[3]
Period (P)67.50 yr
Semi-major axis (a)0.293″
Eccentricity (e)0.788
Inclination (i)45.8°
Longitude of the node (Ω)215.2°
Periastron epoch (T)2049.59 B
Argument of periastron (ω)
(secondary)
82.5°
Details
Luminosity64[2] L
λ Nor A
Mass2.53–2.57[4] M
λ Nor B
Mass2.00–2.13[4] M
Other designations
λ Nor, CD−42°11188, HD 146667, HIP 79963, HR 6071, SAO 226650, WDS J16193-4240[5]
Database references
SIMBADdata

λ Normae, Latinised as Lambda Normae, is a binary star[3] system in the southern constellation of Norma, located near the northern constellation boundary with Scorpius. It is visible to the naked eye as a dim, white-hued point of light that shines with a combined apparent visual magnitude of 5.44.[2] The system is located approximately 350 light years distant from the Sun based on parallax, but is drifting closer with a radial velocity of about −15 km/s.[2]

The pair have an orbital period of 67.5 years with a high eccentricity of 0.788.[3] Both components are A-type main-sequence stars that are generating energy through core hydrogen fusion. The primary component has a visual magnitude of 5.83, and is of class A0V. The fainter secondary is class A3V with a magnitude 6.86.[6]

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): 653–64. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 3.2 3.3 "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/wds/orb6. Retrieved 16 May 2017. 
  4. 4.0 4.1 Cvetkovic, Z.; Ninkovic, S. (2010), "On the Component Masses of Visual Binaries", Serbian Astronomical Journal 180 (180): 71–80, doi:10.2298/SAJ1080071C, Bibcode2010SerAJ.180...71C 
  5. "lam Nor". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=lam+Nor. 
  6. last, O. Yu.; Tamazian, V. S.; Docobo, J. A.; Chulkov, D. A. (2012). "Dynamical masses of a selected sample of orbital binaries". Astronomy & Astrophysics 546: 5. doi:10.1051/0004-6361/201219774. A69. Bibcode2012A&A...546A..69M.