V1936 Aquilae

V1936 Aquilae

A visual band light curve for V1936 Aquilae, plotted from ASAS-SN data[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Aquila
Right ascension	19^h 23^m 47.64119^s[2]
Declination	14° 36′ 39.0612″[2]
Apparent magnitude (V)	15.1
Characteristics
Evolutionary stage	Blue supergiant
Spectral type	O4I[3]
Variable type	cLBV[4]
Astrometry
Proper motion (μ)	RA: +6.500[2] mas/yr Dec.: −55.796[2] mas/yr
Parallax (π)	0.1462 ± 0.0.598 mas[2]
Distance	6,000[5] pc
Details
Mass	25[5] M☉
Radius	48 - 145[6] R☉
Luminosity	562,000[5] L☉
Temperature	13,213[5] K
Age	2.3 (3-6)[7] Myr
Other designations
LS1, 2MASS J19234764+1436391
Database references
SIMBAD	data

V1936 Aquilae is a blue supergiant and candidate Luminous blue variable located in the nebula Westerhout 51, in the constellation Aquila, about 20,000 light years away. The star was originally identified as a massive star in 2000,[3] and was thought to be an O-type supergiant. However, subsequent analyses have shown it to be not O but B-type,[5] as well as being possibly an LBV.[4] The star was shown to be a variable star by Luboš Kohoutek and R. Wehmeyer in 2004.[8]

Properties

V1936 Aquilae is a very luminous star. Recent measurements hint at a bolometric luminosity of around 560,000 L_☉, assuming a distance of 6 kiloparsecs, consistent with the distance of Westerhout 51, the very large H II region (nebula) it is located in. The star likely has a temperature of around 13,200 K.[5] The Stefan-Boltzmann Law suggests a radius of around 143 times that of the Sun.

References

1. "ASAS-SN Variable Stars Database". ASAS-SN Variable Stars Database. ASAS-SN. Retrieved 6 January 2022.
2. 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. Okumura, Shin-ichiro; Mori, Atsushi; Nishihara, Eiji; Watanabe, Etsuji; Yamashita, Takuya (2000-11-01). "The Initial Mass Function of a Massive Star-forming Region W51". The Astrophysical Journal. 543 (2): 799–821. Bibcode:2000ApJ...543..799O. doi:10.1086/317116. ISSN 0004-637X. S2CID 120384418.
4. Smith, Nathan; Aghakhanloo, Mojgan; Murphy, Jeremiah W.; Drout, Maria R.; Stassun, Keivan G.; Groh, Jose H. (2019-09-01). "On the Gaia DR2 distances for Galactic luminous blue variables". Monthly Notices of the Royal Astronomical Society. 488 (2): 1760–1778. arXiv:1805.03298. Bibcode:2019MNRAS.488.1760S. doi:10.1093/mnras/stz1712. ISSN 0035-8711.
5. Bik, A.; Henning, Th.; Wu, S. -W.; Zhang, M.; Brandner, W.; Pasquali, A.; Stolte, A. (2019-04-01). "Near-infrared spectroscopy of the massive stellar population of W51: evidence for multi-seeded star formation". Astronomy and Astrophysics. 624: A63. arXiv:1902.05460. Bibcode:2019A&A...624A..63B. doi:10.1051/0004-6361/201935061. ISSN 0004-6361. S2CID 118711844.
6. Clark, J. S.; Davies, B.; Najarro, F.; MacKenty, J.; Crowther, P. A.; Messineo, M.; Thompson, M. A. (2009). "The P Cygni supergiant [OMN2000] LS1 - implications for the star formation history of W51". Astronomy and Astrophysics. 504 (2): 429. arXiv:0909.3934. Bibcode:2009A&A...504..429C. doi:10.1051/0004-6361/200911980. S2CID 2609634.
7. Lim, Wanggi; De Buizer, James M. (2019). "Surveying the Giant H II Regions of the Milky Way with SOFIA. I. W51A". The Astrophysical Journal. 873 (1): 51. arXiv:1901.07561. Bibcode:2019ApJ...873...51L. doi:10.3847/1538-4357/ab0288.
8. Kohoutek, L.; Wehmeyer, R. (December 2004). "New variable stars among or near to H-alpha emission stars". Astronomische Nachrichten. 325 (9): 723–725. Bibcode:2004AN....325..723K. doi:10.1002/asna.200310253. Retrieved 23 November 2024.