Astronomy:HD 96919

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Short description: Variable star in the constellation Carina
V371 Carinae
Carina constellation map.svg
Red circle.svg
Location of V371 Carinae (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Carina
Right ascension  11h 08m 33.99848s[1]
Declination −61° 56′ 49.8316″[1]
Apparent magnitude (V) 5.19[2] (5.12 - 5.19[3])
Characteristics
Spectral type B9 Iae[4]
U−B color index −0.46[2]
B−V color index +0.23[2]
Variable type α Cyg[3]
Astrometry
Radial velocity (Rv)−22.4 ± 2[5] km/s
Proper motion (μ) RA: −5.78[1] mas/yr
Dec.: 1.74[1] mas/yr
Parallax (π)0.23 ± 0.25[1] mas
Distance1,920[6] pc
Absolute magnitude (MV)−7.0[6]
Details
Mass23[4] M
Radius141[4] R
Luminosity105,000[7] L
Surface gravity (log g)1.50[4] cgs
Temperature12,500[7] K
Rotational velocity (v sin i)60[4] km/s
Other designations
z2 Carinae, V371 Carinae, 261 G. Carinae,[8] CD−61°2941, CPD−61°2075, CPC 20.1 3080, FK5 2891, GC 15331, GCRV 6856, GSC 08962-02640, HD 96919, HIC 54461, HIP 54461, HR 4338, PPM 358516, SAO 251286
Database references
SIMBADdata

HD 96919, also known by its Bayer designation of z2 Carinae and the variable star designation of V371 Carinae, is a blue supergiant star in the constellation Carina. It lies near the Carina Nebula and at a comparable distance.

A light curve for V371 Carinae, plotted from Hipparcos data[9]

V371 Car is an α Cyg variable, erratically pulsating and changing brightness by a few hundredths of a magnitude. Periods of 10–80 days have been identified.[7] It shows unusual emission lines in its spectrum, and high-velocity absorption (HVA) events, temporary spectral features that are thought to indicate localised regions of enhanced mass loss.[10]

HD 96919 is a B9 supergiant, possibly located 6,000 light-years from Earth. It is considered to be a post-red supergiant star, either evolving towards a Wolf–Rayet star or on a blue loop before returning to a cooler temperature.[7]

References

  1. 1.0 1.1 1.2 1.3 1.4 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues 2237: 0. Bibcode2002yCat.2237....0D. 
  3. 3.0 3.1 Samus, N. N. et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S 1. Bibcode2009yCat....102025S. 
  4. 4.0 4.1 4.2 4.3 4.4 Kaufer, A.; Stahl, O.; Wolf, B.; Gaeng, T.; Gummersbach, C. A.; Kovacs, J.; Mandel, H.; Szeifert, T. (1996). "Long-term spectroscopic monitoring of BA-type supergiants. I. Halpha_ line-profile variability". Astronomy and Astrophysics 305: 887. Bibcode1996A&A...305..887K. 
  5. Wilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Washington. Bibcode1953GCRV..C......0W. 
  6. 6.0 6.1 Kaltcheva, N.; Scorcio, M. (2010). "The Carina spiral feature: Strömgren-β photometry approach. II. Distances and space distribution of the O and B stars". Astronomy and Astrophysics 514: A59. doi:10.1051/0004-6361/200913399. Bibcode2010A&A...514A..59K. 
  7. 7.0 7.1 7.2 7.3 Saio, Hideyuki; Georgy, Cyril; Meynet, Georges (2013). "Evolution of blue supergiants and α Cygni variables: Puzzling CNO surface abundances". Monthly Notices of the Royal Astronomical Society 433 (2): 1246. doi:10.1093/mnras/stt796. Bibcode2013MNRAS.433.1246S. 
  8. Gould, Benjamin Apthorp (1879). "Brightness and position of every star, down to the seventh magnitude, within one hundred degrees of the South Pole". Resultados del Observatorio Nacional Argentino 1: I. Bibcode1879RNAO....1....1G. 
  9. "Hipparcos Tools Interactive Data Access". ESA. https://www.cosmos.esa.int/web/hipparcos/interactive-data-access. 
  10. Kaufer, A.; Stahl, O.; Wolf, B.; Gaeng, T.; Gummersbach, C. A.; Jankovics, I.; Kovacs, J.; Mandel, H. et al. (1996). "Long-term spectroscopic monitoring of BA-type supergiants. II. High-velocity absorptions in βOri and HD96919". Astronomy and Astrophysics 314: 599. Bibcode1996A&A...314..599K.