CK Carinae

Summary

CK Carinae (CK Car / HD 90382 / SAO 238038) is a variable star in the constellation Carina, the keel of Argo Navis. It is a member of the star association Carina OB1-D, at a distance of around 2,300 parsecs or 7,500 light years.

CK Carinae

An I band (near infrared) light curve for CK Carinae, plotted from ASAS data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Carina
Right ascension 10h 24m 25.36s[2]
Declination −60° 11′ 29.0″[2]
Apparent magnitude (V) 7.2 - 8.5[3]
Characteristics
Spectral type M3.5 Iab[4]
B−V color index +2.21[2]
Variable type SRc[4]
Astrometry
Radial velocity (Rv)-3.92[5] km/s
Proper motion (μ) RA: -7.351[5] mas/yr
Dec.: 2.995[5] mas/yr
Parallax (π)0.4286 ± 0.0806 mas[5]
Distance2,920+190
−150
[6] pc
Absolute magnitude (MV)−6.31[2]
Details[2]
Mass6.0[7] M
Radius761[8] - 1,060[2] R
Luminosity86,000[8] - 158,000[6] L
Surface gravity (log g)-0.15[7] cgs
Temperature3,550[8] K
Metallicity [Fe/H]0.05[7] dex
Other designations
CK Car, CD−59°3058, HD 90382, SAO 238038
Database references
SIMBADdata

Classified as a semiregular variable star, CK Carinae's brightness varies between apparent magnitudes +7.2 and +8.5 with a period of approximately 525 days.[3] It has a Gaia Data Release 2 parallax of 0.4286±0.0806 mas,[5] which implies a distance of around 2,300 pc, and is thought to be a member of the Carina OB1-D stellar association which is at a distance of about 2,200 pc.[2][8] An analysis of the distances of apparently-nearby OB stars implies a distance of 2,920 pc for CK Carinae.[6] It has an MK spectral classification of M3.5 Iab, with the luminosity class indicating an intermediate luminosity supergiant.[4]

CK Carinae is a red supergiant with an effective temperature of 3,550 K. It is one of the largest stars, with a radius 761 to 1,060 times larger than the sun, which means that if it were in the place of the Sun, its surface would reach beyond the asteroid belt, Earth being encompassed within the star. Consequently, CK Carinae is also a luminous star, radiating between 86,000 and 158,000 times as much energy as the sun.

See also edit

References edit

  1. ^ "ASAS All Star Catalogue". The All Sky Automated Survey. Retrieved 8 December 2021.
  2. ^ a b c d e f g Levesque, Emily M.; Massey, Philip; Olsen, K. A. G.; Plez, Bertrand; Josselin, Eric; Maeder, Andre; Meynet, Georges (August 2005). "The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not As Cool As We Thought". The Astrophysical Journal. 628 (2): 973–985. arXiv:astro-ph/0504337. Bibcode:2005ApJ...628..973L. doi:10.1086/430901. S2CID 15109583.
  3. ^ a b Kiss, L. L.; Szabó, Gy. M.; Bedding, T. R. (2006). "Variability in red supergiant stars: Pulsations, long secondary periods and convection noise". Monthly Notices of the Royal Astronomical Society. 372 (4): 1721–1734. arXiv:astro-ph/0608438. Bibcode:2006MNRAS.372.1721K. doi:10.1111/j.1365-2966.2006.10973.x. S2CID 5203133.
  4. ^ 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.
  5. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  6. ^ a b c Davies, Ben; Beasor, Emma R. (March 2020). "The 'red supergiant problem': the upper luminosity boundary of Type II supernova progenitors". MNRAS. 493 (1): 468–476. arXiv:2001.06020. Bibcode:2020MNRAS.493..468D. doi:10.1093/mnras/staa174. S2CID 210714093.
  7. ^ a b c Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; De Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. S2CID 131780028.
  8. ^ a b c d 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. arXiv:1905.03744. Bibcode:2019AJ....158...20M. doi:10.3847/1538-3881/ab1cbd. S2CID 148571616.