Astronomy:GZ Velorum

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Short description: Star in the constellation Vela
GZ Velorum
Location of GZ Velorum (circled in red)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Vela
Right ascension  10h 19m 36.75198s[1]
Declination −55° 01′ 45.4852″[1]
Apparent magnitude (V) 4.578[2]
Characteristics
Spectral type K2.5 II[3]
B−V color index +1.635[2]
Variable type LC[4]
Astrometry
Radial velocity (Rv)+12.9±0.8[5] km/s
Proper motion (μ) RA: −13.208[1] mas/yr
Dec.: +1.232[1] mas/yr
Parallax (π)2.4256 ± 0.1938[1] mas
Distance1,300 ± 100 ly
(410 ± 30 pc)
Absolute magnitude (MV)−4.16[6]
Details
Mass8.9±0.5[7] M
Radius136[8] R
Luminosity2,679 - 2,780[8] L
Surface gravity (log g)2.0[9] cgs
Temperature3,986[8] K
Metallicity [Fe/H]−0.4[9] dex
Rotational velocity (v sin i)2.0[9] km/s
Age29.6±3.8[7] Myr
Other designations
GZ Vel, CD−54°3415, FK5 2830, HD 89682, HIP 50555, HR 4063, SAO 237916[10]
Database references
SIMBADdata

GZ Velorum is a single,[11] orange-hued star in the southern constellation of Vela. It is a faint star but visible to the naked eye, having an apparent visual magnitude of 4.58.[2] The star is located around 1,300 light years from Earth, as determined from its annual parallax shift of 2.4 mas.[1] It is moving further away with a heliocentric radial velocity of +13 km/s.[5]

An R band light curve for GZ Velorum, adapted from Kallinger (2019)[12]

This is a bright giant star with a stellar classification of K2.5 II.[3] The star was found to be a variable star when the Hipparcos data was analyzed, in 1996.[13] It is a slow irregular variable of type LC[4] with a frequency of 0.16585 cycles per day.[14] In the R (red) band, the magnitude of the star ranges from 3.43 down to 3.81.[4] The measured angular diameter of this star, after correction for limb darkening, is 3.17±0.04 mas.[15] At the estimated distance of GZ Vel, this yields a physical size of about 140 times the radius of the Sun.[16]

GZ Vel is 30 million years old with 9 times the mass of the Sun.[7] It is radiating 9,241[2] times the Sun's luminosity from its photosphere at an effective temperature of 4,140 K.[2]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 2.4 Hohle, M.M. et al. (2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten 331 (4): 349, doi:10.1002/asna.200911355, Bibcode2010AN....331..349H. 
  3. 3.0 3.1 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series 71: 245, doi:10.1086/191373, Bibcode1989ApJS...71..245K. 
  4. 4.0 4.1 4.2 Samus', N. N; Kazarovets, E. V; Durlevich, O. V; Kireeva, N. N; Pastukhova, E. N (2017), "General catalogue of variable stars: Version GCVS 5.1", Astronomy Reports 61 (1): 80–88, doi:10.1134/S1063772917010085, Bibcode2017ARep...61...80S. 
  5. 5.0 5.1 Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system", Astronomy Letters 32 (11): 759–771, doi:10.1134/S1063773706110065, Bibcode2006AstL...32..759G. 
  6. Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  7. 7.0 7.1 7.2 Tetzlaff, N. et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society 410 (1): 190–200, doi:10.1111/j.1365-2966.2010.17434.x, Bibcode2011MNRAS.410..190T 
  8. 8.0 8.1 8.2 Messineo, M.; Brown, A. G. A. (2019). "A Catalog of Known Galactic K-M Stars of Class I Candidate Red Supergiants in Gaia DR2". The Astronomical Journal 158 (1): 20. doi:10.3847/1538-3881/ab1cbd. Bibcode2019AJ....158...20M. 
  9. 9.0 9.1 9.2 Lèbre, A. et al. (May 2006), "Lithium abundances and rotational behavior for bright giant stars", Astronomy and Astrophysics 450 (3): 1173–1179, doi:10.1051/0004-6361:20053485, Bibcode2006A&A...450.1173L, https://repositorio.ufrn.br/bitstream/123456789/29002/1/LithiumAbundancesAndRotationalBehavior_2006.pdf. 
  10. "HD 89682". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+89682. 
  11. Fuhrmann, K. et al. (2017), "Multiplicity among Solar-type Stars", The Astrophysical Journal 836 (1): 139, doi:10.3847/1538-4357/836/1/139, Bibcode2017ApJ...836..139F. 
  12. Kallinger, T.; Beck, P. G.; Hekker, S.; Huber, D.; Kuschnig, R.; Rockenbauer, M.; Winter, P. M.; Weiss, W. W. et al. (April 2019). "Stellar masses from granulation and oscillations of 23 bright red giants observed by BRITE-Constellation". Astronomy and Astrophysics 624: A35. doi:10.1051/0004-6361/201834514. Bibcode2019A&A...624A..35K. 
  13. Kazarovets, E. V.; Samus, N. N.; Durlevich, O. V.; Frolov, M. S.; Antipin, S. V.; Kireeva, N. N.; Pastukhova, E. N. (January 1999). "The 74th Special Name-list of Variable Stars". Information Bulletin on Variable Stars. Bibcode1999IBVS.4659....1K. https://ibvs.konkoly.hu/pub/ibvs/4601/4659.pdf. 
  14. Koen, Chris; Eyer, Laurent (March 2002), "New periodic variables from the Hipparcos epoch photometry", Monthly Notices of the Royal Astronomical Society 331 (1): 45–59, doi:10.1046/j.1365-8711.2002.05150.x, Bibcode2002MNRAS.331...45K. 
  15. Richichi, A. et al. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics 431 (2): 773–777, doi:10.1051/0004-6361:20042039, Bibcode2005A&A...431..773R. 
  16. Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1, https://books.google.com/books?id=OvTjLcQ4MCQC&pg=PA41 . The radius (R*) is given by:
    2R*=(4123.17103) AU0.0046491 AU/R281R