QU Normae

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

QU Normae
Norma constellation map.svg
Red circle.svg
Location of QU Normae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Norma
Right ascension 16h 29m 42.32668s[1]
Declination −46° 14′ 35.6022″[1]
Apparent magnitude (V) 5.37[2] (5.27 - 5.41[3])
Characteristics
Spectral type B1.5 Iap[4]
U−B color index −0.44[2]
B−V color index +0.62[2]
Variable type α Cyg[3]
Astrometry
Radial velocity (Rv)−14.80 ± 3.2[5] km/s
Proper motion (μ) RA: −4.54[1] mas/yr
Dec.: −1.51[1] mas/yr
Parallax (π)1.79 ± 0.70[1] mas
Distanceapprox. 1,800 ly
(approx. 600 pc)
Absolute magnitude (MV)−7.50[6]
Details
Mass43[7] M
Radius58[8] R
Luminosity417,000[6] L
Surface gravity (log g)2.00[7] cgs
Temperature17,000[7] K
Rotational velocity (v sin i)44[7] km/s
Other designations
QU Normae, HD 148379, HIP 80782, HR 6131, CD−45°10697
Database references
SIMBADdata

QU Normae, also known as HR 6131, is a blue supergiant star in the constellation Norma. It is also a variable star, thought to be an α Cyg variable.

The apparent magnitude of QU Normae varies somewhat irregularly between 5.27 and 5.41. The General Catalogue of Variable Stars quotes a period of 4.818 days,[3] but other research only shows likely periods longer than 10 days.[9]

QU Normae has a spectral type B1.5 Ia, a luminous supergiant that has swollen and cooled off the main sequence. Surface abundances suggest that it has not yet passed through a red supergiant phase.[6] Around 1,820 light-years distant, it shines with a luminosity approximately 417,000 times that of the Sun and has a diameter around 58 times that of the Sun.

References[edit]

  1. ^ a b c d e Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
  2. ^ a b c 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. Bibcode:2002yCat.2237....0D.
  3. ^ a b c Samus, N. N.; Durlevich, O. V.; 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. Bibcode:2009yCat....102025S.
  4. ^ Chini, R.; Hoffmeister, V. H.; Nasseri, A.; Stahl, O.; Zinnecker, H. (2012). "A spectroscopic survey on the multiplicity of high-mass stars". Monthly Notices of the Royal Astronomical Society. 424 (3): 1925. arXiv:1205.5238. Bibcode:2012MNRAS.424.1925C. doi:10.1111/j.1365-2966.2012.21317.x.
  5. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065.
  6. ^ a b c Lennon, D. J.; Dufton, P. L. (1986). "Evolutionary effects on the surface abundances of an early-type supergiant". Astronomy and Astrophysics. 155: 79. Bibcode:1986A&A...155...79L.
  7. ^ a b c d Fraser, M.; Dufton, P. L.; Hunter, I.; Ryans, R. S. I. (2010). "Atmospheric parameters and rotational velocities for a sample of Galactic B-type supergiants". Monthly Notices of the Royal Astronomical Society. 404: 1306. arXiv:1001.3337. Bibcode:2010MNRAS.404.1306F. doi:10.1111/j.1365-2966.2010.16392.x.
  8. ^ Van Leeuwen, F.; Van Genderen, A. M.; Zegelaar, I. (1998). "Hipparcos photometry of 24 variable massive stars (α Cygni variables)". Astronomy and Astrophysics Supplement Series. 128: 117. Bibcode:1998A&AS..128..117V. doi:10.1051/aas:1998129.