Lambda Lupi

Lambda Lupi
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Lupus
Right ascension 15h 08m 50.61639s[1]
Declination −45° 16′ 47.4950″[1]
Apparent magnitude (V) 4.04[2] (4.43 + 5.23)[3]
Characteristics
Spectral type B3 V[4] (B3 V + B3 V)[5]
U−B color index −0.67[2]
B−V color index −0.18[2]
Astrometry
Radial velocity (Rv)+9.80±1.78[6] km/s
Proper motion (μ) RA: −15.88[1] mas/yr
Dec.: −26.80[1] mas/yr
Parallax (π)4.20 ± 0.66 mas[1]
Distanceapprox. 800 ly
(approx. 240 pc)
Absolute magnitude (MV)−2.75[7]
Orbit[8]
Period (P)70.8±0.8 yr
Semi-major axis (a)0.2597±0.0021″
Eccentricity (e)0.6283±0.0090
Inclination (i)71.59±0.41°
Longitude of the node (Ω)26.64±0.61°
Periastron epoch (T)1997.907 ± 0.105
Argument of periastron (ω)
(secondary)		299.9±1.1°
Details
λ Lup A
Mass8.14[8] M☉
Rotational velocity (v sin i)135 km/s
Age28.1±4.1[9] Myr
λ Lup B
Mass5.84 M☉
Other designations
λ Lup, CD−44° 9889, HD 133955, HIP 74117, HR 5626, SAO 225483, WDS J15088-4517AB.[10]
Database references
SIMBADdata

Lambda Lupi, Latinized from λ Lupi, is a triple star[11] system in the southern constellation of Lupus. It is visible to the naked eye with a combined apparent visual magnitude of 4.04.[2] Based upon an annual parallax shift of just 4.20[1] mas as seen from Earth, it is located roughly 800 light years from the Sun. The system has a peculiar velocity of 27.4±4.9 km/s relative to its neighbors, making it a candidate runaway star system.[9] It is a member of the Upper Centaurus–Lupus sub-group in the Scorpius–Centaurus OB association.[12]

The two visible components of this system orbit each other over a period of 70.8 years with a large eccentricity of 0.63.[8] The primary component has a visual magnitude of 4.43, while the secondary is of magnitude 5.23.[3] Both are B-type main sequence stars with a stellar classification of B3 V.[5] One of the pair is itself a double-lined spectroscopic binary, making this a triple star system.[11]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Mermilliod1986 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Edwards1976 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference Tokovinin2012 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference Mitschelm2004 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Wolff2007 was invoked but never defined (see the help page).