Astronomy:AH Scorpii
Observation data Equinox J2000.0]] (ICRS) | |
---|---|
Constellation | Scorpius |
Right ascension | 17h 11m 17.01945s[1] |
Declination | −32° 19′ 30.7140″[1] |
Characteristics | |
Spectral type | M4-5 Ia-Iab[2] |
B−V color index | +2.57[3] |
Variable type | SRc[2] |
Astrometry | |
Radial velocity (Rv) | −13.40±2.4[4] km/s |
Proper motion (μ) | RA: −2.322±0.115[1] mas/yr Dec.: −2.610±0.068[1] mas/yr |
Parallax (π) | 0.5632 ± 0.0799[1] mas |
Distance | 7,400±620 ly (2,260±190[5] pc) |
Absolute magnitude (MV) | −5.8[6] |
Details | |
Mass | 10[5] M☉ |
Radius | 1,411±124[3] R☉ |
Luminosity | 330,000+270,000 −150,000[3] L☉ |
Surface gravity (log g) | −0.5[3] cgs |
Temperature | 3,450[7] - 3,682[3] K |
Other designations | |
Database references | |
SIMBAD | data |
AH Scorpii (abbreviated to AH Sco) is a red supergiant variable star located in the constellation Scorpius. It is one of the largest stars known by radius and is also one of the most luminous red supergiant stars in the Milky Way.
Distance
The distance of AH Scorpii is considered to be uncertain. VLBI measurements of the masers have provided an accurate distance of 2,260 parsecs based on observation of SiO, H2O, and OH masers in its oxygen-rich circumstellar material. The masers were observed to be approaching the star at 13 km/s, indicating overall contraction at around phase 0.55 of the visual variations.[5]
Characteristics
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AH Scorpii is a dust-enshrouded red supergiant[9] and is classified as a semiregular variable star with a main period of 714 days. The total visual magnitude range is 6.5 - 9.6.[10] No long secondary periods have been detected.[11] Modelling of AH Scorpii near maximum light has determined an effective temperature of 3,682±190 K and a luminosity of 330,000+270,000
−150,000 L☉. A radius of 1,411±124 R☉ was determined from an angular diameter of 5.81±0.15 mas and the given distance of 2.26±0.19 kpc.[3]
See also
References
- ↑ Jump up to: 1.0 1.1 1.2 1.3 1.4 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ Jump up to: 2.0 2.1 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. Bibcode: 2009yCat....102025S.
- ↑ Jump up to: 3.0 3.1 3.2 3.3 3.4 3.5 Arroyo-Torres, B.; Wittkowski, M.; Marcaide, J. M.; Hauschildt, P. H. (2013). "The atmospheric structure and fundamental parameters of the red supergiants AH Scorpii, UY Scuti, and KW Sagittarii". Astronomy & Astrophysics 554: A76. doi:10.1051/0004-6361/201220920. Bibcode: 2013A&A...554A..76A.
- ↑ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. Bibcode: 2006AstL...32..759G.
- ↑ Jump up to: 5.0 5.1 5.2 Chen, Xi; Shen, Zhi-Qiang (2008). "VLBI Observations of SiO Masers around AH Scorpii". The Astrophysical Journal 681 (2): 1574–1583. doi:10.1086/588186. Bibcode: 2008ApJ...681.1574C.
- ↑ Baudry, A.; Le Squeren, A. M.; Lepine, J. R. D. (1977). "The supergiant OH stars S Per and AH SCO - Conditions for OH emission in circumstellar envelopes". Astronomy and Astrophysics 54: 593. Bibcode: 1977A&A....54..593B.
- ↑ Messineo, M.; Brown, A. G. A. (2019). "A Catalog of Known Galactic K-M Stars of Class I Candidate Red Supergiants in Gaia DR2". The Astronomical Journal 158 (1): 20. doi:10.3847/1538-3881/ab1cbd. Bibcode: 2019AJ....158...20M.
- ↑ "Download Data". AAVSO. https://www.aavso.org/data-download.
- ↑ Van Loon, J. Th.; Cioni, M.-R. L.; Zijlstra, A. A.; Loup, C. (2005). "An empirical formula for the mass-loss rates of dust-enshrouded red supergiants and oxygen-rich Asymptotic Giant Branch stars". Astronomy and Astrophysics 438 (1): 273–289. doi:10.1051/0004-6361:20042555. Bibcode: 2005A&A...438..273V.
- ↑ Cite error: Invalid
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- ↑ Percy, John R.; Sato, Hiromitsu (2009). "Long Secondary Periods in Pulsating Red Supergiant Stars". Journal of the Royal Astronomical Society of Canada 103 (1): 11. Bibcode: 2009JRASC.103...11P.
![]() | Original source: https://en.wikipedia.org/wiki/AH Scorpii.
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