R Cassiopeiae
Star in the constellation Cassiopeia / From Wikipedia, the free encyclopedia
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.
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] |
Distance | 176[6] pc |
Details | |
Mass | 0.59[7] M☉ |
Radius | 263[7]–310[8] R☉ |
Luminosity | 8,960[6] L☉ |
Temperature | 2,812[7] K |
Other designations | |
Database references | |
SIMBAD | data |
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]