Zeta Lupi

ζ Lupi
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Lupus
Right ascension 15h 12m 17.09595s[1]
Declination −52° 05′ 57.2919″[1]
Apparent magnitude (V) 3.41[2] (3.50 + 6.74)[3]
Characteristics
Spectral type G7 III[4]
U−B color index +0.66[2]
B−V color index +0.92[2]
Astrometry
Radial velocity (Rv)−10.0±0.6[5] km/s
Proper motion (μ) RA: −112.92[1] mas/yr
Dec.: −71.18[1] mas/yr
Parallax (π)27.80 ± 0.15 mas[1]
Distance117.3 ± 0.6 ly
(36.0 ± 0.2 pc)
Absolute magnitude (MV)0.65[6]
Details
ζ Lup A
Mass2.29[6] M☉
Radius10[7] R☉
Luminosity53[8] L☉
Surface gravity (log g)3.01[9] cgs
Temperature5,335[8] K
Metallicity [Fe/H]0.00±0.02[9] dex
Other designations
ζ Lup, CD−51°8830, FK5 558, GJ 9512 A, HD 134505, HIP 74395, HR 5649, SAO 242304, WDS J15123-5206A[10]
Database references
SIMBADdata

ζ Lupi (Latinised as Zeta Lupi) is the brighter component of a wide double star in the constellation Lupus, consisting of an orange-hued primary and a fainter secondary with a golden-yellow hue.[11] It is visible to the naked eye with a combined apparent visual magnitude of 3.41.[2] Based upon an annual parallax shift of 27.80[1] mas as seen from Earth, it is located 117.3 light-years from the Sun.

This is a probable binary star system.[12] As of 2013, the pair had an angular separation of 71.20 arcseconds along a position angle of 249°.[3] The primary, component A, is an evolved G-type giant star with a visual magnitude of 3.50[3] and a stellar classification of G7 III.[4] This is a red clump star, indicating that it is generating energy through the thermonuclear fusion of helium in its core region.[13] Its measured angular diameter is 2.55±0.13 mas,[14] which, at the estimated distance of Zeta Lupi, yields a physical size of about 10 times the radius of the Sun.[7]

The secondary, component B, has a visual magnitude of 6.74.[3]

  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 Johnson1966 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Gray2006 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Pizzolato2000 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference lang2006 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Mcdonald2012 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Soubiran2016 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. ^ Cite error: The named reference Streicher2007 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference laney2012 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Richichi2005 was invoked but never defined (see the help page).