HD 88366

This article is about the Mira variable S Carinae. For s Carinae, see HD 90853.
S Carinae

The visual band light curve of S Carinae, from AAVSO data[1]
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Carina
Right ascension 10h 09m 21.894s[2]
Declination −61° 32′ 56.43″[2]
Apparent magnitude (V) 4.5 - 10.0[3]
Characteristics
Evolutionary stage AGB[4]
Spectral type K5e - M6e[3]
U−B color index +0.93 to +1.93[5]
B−V color index +1.43 to +2.60[5]
Variable type Mira[3]
Astrometry
Radial velocity (Rv)289.30[6] km/s
Proper motion (μ) RA: −94.237[2] mas/yr
Dec.: 76.811[2] mas/yr
Parallax (π)2.0110 ± 0.0855 mas[2]
Distance1,620 ± 70 ly
(500 ± 20 pc)
Absolute magnitude (MV)−0.71 to −3.41[7]
Details
Mass0.6[8] M☉
Radius120[8] R☉
Luminosity2,200[5] L☉
Surface gravity (log g)−0.9 - 1.0[9] cgs
Temperature3,050 - 3,590[9] K
Other designations
HR 3999, HD 88366, CP−60°1701, HIP 49751, SAO 250840, GC 13971
Database references
SIMBADdata

S Carinae (HD 88366) is a variable star in the constellation Carina.

S Carinae is an M-type red giant with a mean apparent magnitude of +6.94. It is approximately 1,620 light years from Earth. It is classified as a Mira type variable star and its brightness varies between magnitude +4.5 and +10.0 with a period of 149.49 days.[3] It has one of the earliest spectral types, and hence the hottest temperatures, of any Mira variable, and has a relatively short period for the class.[10] The temperature of this pulsing star is highest at visual brightness maximum and lowest at visual brightness minimum.[9]

S Carinae has exhausted its core hydrogen and expanded to become a red giant. It has also exhausted its core helium and evolved to the asymptotic giant branch, where it fuses hydrogen and helium in separate shells outside the core.[10][4]

References

  1. ^ "Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.
  2. ^ 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.
  3. ^ a b c d 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: B/gcvs. Bibcode:2009yCat....102025S.
  4. ^ a b Eggen, Olin J. (1992). "Asymptotic Giant Branch Stars Near the Sun". The Astronomical Journal. 104: 275. Bibcode:1992AJ....104..275E. doi:10.1086/116239.
  5. ^ a b c Eggen, O. J. (1972). "Narrow-and broad-band photometry of red stars. VII. Luminosities and temperatures for halo-population red stars of high luminosity". The Astrophysical Journal. 172: 639. Bibcode:1972ApJ...172..639E. doi:10.1086/151383.
  6. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  7. ^ Celis, L. (1995). "Luminosity Attenuation and Distances of Red Giant Stars". The Astrophysical Journal Supplement Series. 98: 701. Bibcode:1995ApJS...98..701C. doi:10.1086/192175.
  8. ^ a b Willson, L. A.; Wallerstein, G.; Pilachowski, C. A. (1982). "Atmospheric kinematics of high velocity long period variables". Monthly Notices of the Royal Astronomical Society. 198 (2): 483–516. Bibcode:1982MNRAS.198..483W. doi:10.1093/mnras/198.2.483.
  9. ^ a b c Shinkawa, Donna (1973). "The Mira Variable S Carinae". The Astrophysical Journal Supplement Series. 25: 253. Bibcode:1973ApJS...25..253S. doi:10.1086/190269.
  10. ^ a b Schultheis, M.; Glass, I. S. (2001). "Asymptotic giant branch variables in Baade's Windows". Monthly Notices of the Royal Astronomical Society. 327 (4): 1193–1200. Bibcode:2001MNRAS.327.1193S. doi:10.1046/j.1365-8711.2001.04825.x.