Theta Columbae

θ Columbae
(Elkurud)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Columba
Right ascension 06h 07m 31.63216s[1]
Declination −37° 15′ 10.5114″[1]
Apparent magnitude (V) 5.02[2]
Characteristics
Spectral type B8 IV[3]
B−V color index −0.11[2]
Astrometry
Radial velocity (Rv)+45.3±1.8[4] km/s
Proper motion (μ) RA: +0.12[1] mas/yr
Dec.: +0.41[1] mas/yr
Parallax (π)4.52 ± 0.16 mas[1]
Distance720 ± 30 ly
(221 ± 8 pc)
Absolute magnitude (MV)−1.72[5]
Details
Mass4.13±0.09[6] M☉
Luminosity472[7] L☉
Temperature9,916[7] K
Rotational velocity (v sin i)249[3] km/s
Age237[8] Myr
Other designations
Elkurud, θ Col, CD−37°2609, FK5 2468, HD 42167, HIP 29034, HR 2177, SAO 196514[9]
Database references
SIMBADdata

Theta Columbae, also named Elkurud /ˈɛlkərʌd/,[10] is a solitary[11] star in the southern constellation of Columba. It is faintly visible to the naked eye, having an apparent visual magnitude of 5.02.[2] Based upon parallax measurements taken during the Hipparcos mission, it is roughly 720 light-years (220 parsecs) distant from the Sun.[1] At its present distance, the visual magnitude of the star is reduced by an interstellar extinction factor of 0.11.[8] It is currently moving away from the Sun with a radial velocity of 45.3 km/s.[4] The star made its closest approach about 4.7 million years ago when it underwent perihelion passage at a distance of 10.9 ly (3.33 pc).[4]

This is an evolving B-type subgiant star with a stellar classification of B8 IV,[3] having recently left the main sequence.[6] It is spinning rapidly with a projected rotational velocity of 249 km/s.[3] The star has an estimated four times the mass of the Sun.[6] It radiates 472 times the solar luminosity from its outer atmosphere at an effective temperature of 9,916 K.[7]

  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 Cite error: The named reference Johnson1999 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference Royer2002 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference BailerJones2015 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 Cite error: The named reference Zorec2012 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Mcdonald2012 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Gontcharov2012 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference IAU-LSN was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).