Astronomy:R Cassiopeiae

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Short description: Star in the constellation Cassiopeia
R Cassiopeiae
RCasLightCurve.png
The visual band light curve of R Cassiopeiae, from AAVSO data[1]
Observation data
Equinox J2000.0]] (ICRS)
Constellation Cassiopeia
Right ascension  23h 58m 24.87003s[2]
Declination +51° 23′ 19.70″[2]
Apparent magnitude (V) 4.4 to 13.5[3]
Characteristics
Spectral type M6e–M10e[3]
U−B color index +0.08[4]
B−V color index +1.83[4]
Variable type Mira[3]
Astrometry
Radial velocity (Rv)−22.94±0.72[5] km/s
Proper motion (μ) RA: 81.920±0.403[2] mas/yr
Dec.: 18.760±0.358[2] mas/yr
Parallax (π)5.3417 ± 0.2449[2] mas
Distance176[6] pc
Details
Mass0.59[7] M
Radius263[7]–310[8] R
Luminosity8,960[6] L
Temperature2,812[7] K
Other designations
R Cas, BD+50°4202, HD 224490, HIP 118188, HR 9066, SAO 35938, ADS 17135, CCDM J23584+5123[9]
Database references
SIMBADdata

R Cassiopeiae is a variable star in the northern constellation of Cassiopeia. It is located approximately 574 light years distant from the Sun, but is drifting closer with a radial velocity of −23 km/s.[5] This is a pulsating Mira-type variable star with a brightness varies from magnitude +4.4 down to +13.5 with a period of 433.6 days.[3] At its maximum, R Cassiopeiae is visible to the naked eye as a faint, red-hued star.

This aging red giant star has a stellar classification that varies from M6e to M10e,[3] where the 'e' suffix indicates emission features in the spectrum. Currently on the asymptotic giant branch,[10] it has 59%[7] of the mass of the Sun with an oxygen rich chemical abundance.[11] Having exhausted the supply of hydrogen at its core, the star has expanded to 263[7]–310[8] times the Sun's radius. On average, the star is radiating 3,837[7] times the luminosity of the Sun from its swollen photosphere with an effective temperature ranging around 2,812 K.[7] It is losing mass at the rate of 1.3×10−6 M/yr−1[6] and is surrounded by a dusty circumstellar shell that extends out to 2.8.[11]

See also

References

  1. "Download Data". AAVSO. https://www.aavso.org/data-download. 
  2. 2.0 2.1 2.2 2.3 2.4 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  3. 3.0 3.1 3.2 3.3 3.4 Samus, N. N. et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1 61 (1): 80–88. doi:10.1134/S1063772917010085. Bibcode2017ARep...61...80S. 
  4. 4.0 4.1 Ducati, J. R. (2002). "Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues 2237: 0. Bibcode2002yCat.2237....0D. 
  5. 5.0 5.1 Famaey, B. et al. (January 2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters". Astronomy and Astrophysics 430 (1): 165–186. doi:10.1051/0004-6361:20041272. Bibcode2005A&A...430..165F. 
  6. 6.0 6.1 6.2 McDonald, I.; De Beck, E.; Zijlstra, A. A.; Lagadec, E. (2018). "Pulsation-triggered dust production by asymptotic giant branch stars". Monthly Notices of the Royal Astronomical Society 481 (4): 4984. doi:10.1093/mnras/sty2607. Bibcode2018MNRAS.481.4984M. 
  7. 7.0 7.1 7.2 7.3 7.4 7.5 7.6 Takeuti, Mine et al. (2013). "A Method to Estimate the Masses of Asymptotic Giant Branch Variable Stars". Publications of the Astronomical Society of Japan 65 (3): 60. doi:10.1093/pasj/65.3.60. Bibcode2013PASJ...65...60T. 
  8. 8.0 8.1 de Beck, E. et al. (2010). "Probing the mass-loss history of AGB and red supergiant stars from CO rotational line profiles. II. CO line survey of evolved stars: derivation of mass-loss rate formulae". Astronomy & Astrophysics 523: A18. doi:10.1051/0004-6361/200913771. Bibcode2010A&A...523A..18D. 
  9. "R Cas". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=R+Cas. 
  10. Assaf, K. A. (December 2018). "Multi-epoch Proper Motion Magnetic Field Comparison of SiO Masers around R Cas". The Astrophysical Journal 869 (1): 19. doi:10.3847/1538-4357/aaea65. 80. Bibcode2018ApJ...869...80A. 
  11. 11.0 11.1 Ueta, T. et al. (May 2010). "The interface between the stellar wind and interstellar medium around R Cassiopeiae revealed by far-infrared imaging". Astronomy and Astrophysics 514: 6. doi:10.1051/0004-6361/200913455. A16. Bibcode2010A&A...514A..16U.