R Cassiopeiae

Not to be confused with Rho Cassiopeiae.
R Cassiopeiae

The visual band light curve of R Cassiopeiae, from AAVSO data[1]
Observation data
Epoch J2000.0      Equinox J2000.0
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 mas[2]
Distance176[6] pc
Details
Mass0.59[7] M☉
Radius263[7] 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[8]
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,[9] it has 59%[7] of the mass of the Sun with an oxygen rich chemical abundance.[10] Having exhausted the supply of hydrogen at its core, the star has expanded to 263[7] 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′.[10]

  1. ^ Cite error: The named reference aavso was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference ducati was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Famaey2005 was invoked but never defined (see the help page).
  6. ^ a b c 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. arXiv:1809.07965. Bibcode:2018MNRAS.481.4984M. doi:10.1093/mnras/sty2607. S2CID 118969263.
  7. ^ a b c d e f g Cite error: The named reference takeuti was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Assaf2018 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Ueta2010 was invoked but never defined (see the help page).