G79.29+0.46

G79.29+0.46

G79.29+0.46 (Spitzer Space Telescope image)
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus[1]
Right ascension 20h 31m 42.2847s[2]
Declination +40° 21′ 59.074″[2]
Apparent magnitude (V) 15.1[3]
Characteristics
Spectral type B:I[e][4]
Astrometry
Radial velocity (Rv)39.02±7.30[2] km/s
Proper motion (μ) RA: −2.925[2] mas/yr
Dec.: −5.339[2] mas/yr
Parallax (π)0.5725±0.0596 mas[2]
Distanceapprox. 5,700 ly
(approx. 1,700 pc)
Absolute magnitude (MV)−10[5]
Details
Luminosity2.51×105[6] L☉
Temperature20,400[6] K
Other designations
GAL 079.29+00.46, GRS G079.29 +00.46, HBHA 4203-09, IRAS 20298+4011, 2MASS J20314228+4021591, WISE J203142.22+402159.0
Database references
SIMBADdata

G79.29+0.46 is a luminous blue variable star candidate located in the Cygnus X star formation region.[2][6] In the infrared and at radio wavelengths a prominent circular nebula can be seen. This nebula was formed by past mass-loss episodes of the LBV candidate.[7]

G79.29+0.46 was first reported as a suspected LBV by Higgs, Wendker & Landecker in 1993 with the DRAO Synthesis Telescope, which identified a nebula around a star that was a wind-blown shell.[8] As an LBV candidate, it has a spectrum with many emission lines, H-alpha being the strongest. The spectrum is similar to other LBVs and Be supergiants. The strength of the H-alpha line suggest very dense winds around this star.[4] The star is currently losing mass at a rate of 1.4×10−6 M☉/year and it is surrounded by a dusty envelope with a temperature of 40 to 1,200 K.[6] The star is considered only a candidate LBV because it has not shown variability in the optical or near-infrared over 20 years. It has been suggested that it is a LBV in the quiescent stage.[6]

From radio and infrared images a detached shell can be seen that shows evidence of two mass-loss episodes.[7] This shell has a mass of 1.51 M☉ and a radius of 0.66 parsecs,[6] and it contains carbon monoxide[9] and ammonia.[7]

  • Spitzer and WISE view of G79.29+0.46, the H II-region DR15 (bright object lower left) and the IRDC G79.3+0.3 (dark clouds)[7]
  • The outer shell is best seen between 20 and 70 Microns, here an image by Spitzer and Herschel.
  • Radio image of G79.29+0.46 at 1.4 GHz

References

  1. ^ Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
  2. ^ a b c d e f g Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ^ Kohoutek, L.; Wehmeyer, R. (1997). "Catalogue of stars in the Northern Milky Way having H-alpha in emission". Astronomische Abhandlungen der Hamburger Sternwarte. 11: 1. Bibcode:1997AAHam..11.....K.
  4. ^ a b Voors, R. H. M.; Geballe, T. R.; Waters, L. B. F. M.; Najarro, F.; Lamers, H. J. G. L. M. (2000-10-01). "Spectroscopy of the candidate luminous blue variable at the center of the ring nebula G79.29+0.46". Astronomy and Astrophysics. 362: 236–244. arXiv:astro-ph/0008293. Bibcode:2000A&A...362..236V. ISSN 0004-6361.
  5. ^ Higgs, L. A.; Wendker, H. J.; Landecker, T. L. (1994-11-01). "G 79.29+0.46: a young stellar-wind shell in Cygnus X.". Astronomy and Astrophysics. 291: 295–309. Bibcode:1994A&A...291..295H. ISSN 0004-6361.
  6. ^ a b c d e f Agliozzo, C.; Noriega-Crespo, A.; Umana, G.; Flagey, N.; Buemi, C.; Ingallinera, A.; Trigilio, C.; Leto, P. (2014-05-01). "The candidate luminous blue variable G79.29+0.46: a comprehensive study of its ejecta through a multiwavelength analysis". Monthly Notices of the Royal Astronomical Society. 440 (2): 1391–1409. arXiv:1402.2983. Bibcode:2014MNRAS.440.1391A. doi:10.1093/mnras/stu296. ISSN 0035-8711.
  7. ^ a b c d Rizzo, J. R.; Palau, Aina; Jiménez-Esteban, F.; Henkel, C. (2014-04-01). "Ammonia observations in the LBV nebula G79.29+0.46. Discovery of a cold ring and some warm spots". Astronomy and Astrophysics. 564: A21. arXiv:1401.6186. Bibcode:2014A&A...564A..21R. doi:10.1051/0004-6361/201323170. ISSN 0004-6361. S2CID 119246133.
  8. ^ Higgs, L. A.; Wendker, H. J.; Landecker, T. L. (1993). "Discovery of a Young Stellar-Wind Shell in Cygnus X". American Astronomical Society Meeting Abstracts. 183. Bibcode:1993AAS...183.5801H.
  9. ^ Rizzo, J. R.; Jiménez-Esteban, F. M.; Ortiz, E. (2008-07-01). "Discovery of Warm and Dense Molecular Gas Surrounding the Ring Nebula G79.29+0.46". The Astrophysical Journal. 681 (1): 355–364. arXiv:0804.0266. Bibcode:2008ApJ...681..355R. doi:10.1086/588455. ISSN 0004-637X. S2CID 17847585.
This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.