VY Canis Majoris

VY Canis Majoris (VY CMa) is a reid hypergiant in the constellation Canis Major. It is ane o the lairgest kent starns bi radius an an aa ane o the maist luminous o its type. It is approximately 1,420 ± 120 solar radii[8] (equal tae 6.6 astronomical units, sicweys a diameter aboot 1,975,000,000 kilometres (1.227×109 mi)), an aboot 1.2 kiloparsec (3,900 light-year) distant frae Yird. VY CMa is a single starn categorized as a semiregular variable an haes an estimatit period o 2,000 days. It haes an average density o 5 tae 10 mg/m3. If placed at the centre o the Solar Seestem, VY Canis Majoris's surface wad extend ayond the orbit o Jupiter, altho thare is still considerable variation in estimates o the radius, wi some makin it lairger than the orbit o Saturn.[11]

VY Canis Majoris

Size comparison atween the Sun an VY Canis Majoris
Observation data
Epoch J2000      Equinox J2000
Constellation Canis Major
Richt ascension 07h 22m 58.32877s[1]
Declination −25° 46′ 03.2355″[1]
Apparent magnitude (V) 6.5 to 9.6[2]
7.9607[3]
Chairactereestics
Spectral type M3[4]-M5e Ia[5]
B−V colour index 2.24[4]
Variable teep Semiregular[6]
Astrometry
Radial velocity (Rv)49 ± 10[4] km/s
Proper motion (μ) RA: 9.84[4] mas/yr
Dec.: 0.75[4] mas/yr
Parallax (π)0.83 ± 0.1[7] mas
Distance~3,840 ly
(1,170[8][9] pc)
Details
Mass17 ± 8[8] M
Radius1420 ± 120[8] R
Luminosity~270,000[8] L
Surface gravity (log g)-0.6[8] cgs
Temperatur~3,490[8] K
Age8.2×106[10] years
Ither designations

References eedit

  1. a b "SIMBAD basic query result: VY Canis Majoris". SIMBAD, Centre de Données astronomiques de Strasbourg. Retrieved 23 Januar 2013.
  2. "GCVS Query=VY CMa". General Catalogue of Variable Stars @ Sternberg Astronomical Institute, Moscow, Russia. Retrieved 24 November 2010.
  3. a b "Hipparchos catalogue: query form". CASU Astronomical Data Centre. Cambridge Astronomical Survey Unit. 2006. Archived frae the original on 3 Mairch 2016. Retrieved 10 Mairch 2009.
  4. a b c d e "SIMBAD basic query result: VY Canis Majoris". SIMBAD, Centre de Données astronomiques de Strasbourg. Retrieved 7 Mairch 2009.
  5. a b Lipscy, S. J.; Jura, M.; Reid, M. J. (10 Juin 2005). "Radio photosphere and mass-loss envelope of VY Canis Majoris". The Astrophysical Journal. The American Astronomical Society. 626 (1): 439–445. arXiv:astro-ph/0502586. Bibcode:2005ApJ...626..439L. doi:10.1086/429900.
  6. Monnier, J. D.; Geballe, T. R.; Danchi, W. C. (1 August 1998). "Temporal variations of midinfrared spectra in late-type stars". The Astrophysical Journal. American Astronomical Society. 502 (2): 833–846. arXiv:astro-ph/9803027. Bibcode:1998ApJ...502..833M. doi:10.1086/305945.
  7. "Distance and Kinematics of the Red Hypergiant VY CM". Retrieved 19 Mey 2012.
  8. a b c d e f g Wittkowski, M.; Hauschildt, P.H.; Arroyo-Torres, B.; Marcaide, J.M. (5 Apryle 2012). "Fundamental properties and atmospheric structure of the red supergiant VY CMa based on VLTI/AMBER spectro-interferometry". Astronomy & Astrophysics. 540: L12. arXiv:1203.5194. Bibcode:2012A&A...540L..12W. doi:10.1051/0004-6361/201219126.
  9. Y. K. Choi; Hirota, Tomoya; Honma, Mareki; Kobayashi, Hideyuki; Bushimata, Takeshi; Imai, Hiroshi; Iwadate, Kenzaburo; Jike, Takaaki; Kameno, Seiji (2008). "Distance to VY VMa with VERA". Publications of the Astronomical Society of Japan. Publications Astronomical Society of Japan. 60: 1007. arXiv:0808.0641. Bibcode:2008PASJ...60.1007C.
  10. Zhang, B.; Reid, M. J.; Menten, K. M.; Zheng, X. W. (December 2011). "DISTANCE AND KINEMATICS OF THE RED HYPERGIANT VY CMa: VERY LONG BASELINE ARRAY AND VERY LARGE ARRAY ASTROMETRY". The Astrophysical Journal (in Inglis). 744 (1): 23. doi:10.1088/0004-637X/744/1/23. ISSN 0004-637X.
  11. Massey, Philip; Levesque, Emily M.; Plez, Bertrand (1 August 2006). "Bringing VY Canis Majoris down to size: an improved determination of its effective temperature". The Astrophysical Journal. 646 (2): 1203–1208. arXiv:astro-ph/0604253. Bibcode:2006ApJ...646.1203M. doi:10.1086/505025.