Theta Lupi

Theta Lupi
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Lupus
Right ascension 16h 06m 35.54525s[1]
Declination −36° 48′ 08.2653″[1]
Apparent magnitude (V) 4.22[2]
Characteristics
Spectral type B2.5 Vn[3]
U−B color index −0.734[2]
B−V color index −0.184[2]
Astrometry
Radial velocity (Rv)+6.0±3.4[4] km/s
Proper motion (μ) RA: −15.33[1] mas/yr
Dec.: −33.83[1] mas/yr
Parallax (π)7.87 ± 0.47 mas[1]
Distance410 ± 20 ly
(127 ± 8 pc)
Absolute magnitude (MV)−1.29[5]
Details
Mass6.5±0.1[6] M☉
Radius4.5[7] R☉
Luminosity792[8] L☉
Surface gravity (log g)4.5[9] cgs
Temperature15,395[8] K
Rotational velocity (v sin i)331[10] km/s
Age24.6±5.2[6] Myr
Other designations
θ Lup, CD−36° 10642, FK5 599, HD 144294, HIP 78918, HR 5987, SAO 207332.[11]
Database references
SIMBADdata

Theta Lupi, Latinized from θ Lupi, is a solitary[12] star in the southern constellation of Lupus. It is visible to the naked eye with an apparent visual magnitude of 4.22.[2] (The planetary nebula NGC 6072 lies 1.4° to the east-northeast.[13]) Based upon an annual parallax shift of 7.87 mas as seen from Earth, it is located roughly 410 light years away from the Sun. Relative to its neighbors, this star has a peculiar velocity of 16.7±3.7 km/s.[14] It is a member of the nearby Sco OB2 association.[12]

This is a B-type main sequence star with a stellar classification of B2.5 Vn,[3] where the 'n' suffix indicates nebulous lines due to spin. It is rotating rapidly with a projected rotational velocity of 331 km/s.[10] This is giving the star an oblate shape with an equatorial bulge that is an estimated 15% larger than the polar radius.[15] The star has an estimated 6.5[6] times the mass of the Sun and around 4.5[7] times the Sun's radius. With an age of just 24.6[6] million years, it is radiating 792 times the solar luminosity from its outer atmosphere at an effective temperature of 15,395 K.[8]

  1. ^ a b c d e 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 GutierrezMoreno1968 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Hiltner1969 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference PasinettiFracassini2001 was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference Mcdonald2012 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Kraus2016 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference UesugiFukuda70 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference Rizzuto2013 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Bakich2010 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Bobylev2013 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference belle2012 was invoked but never defined (see the help page).