48 Cassiopeiae
48 Cassiopeiae is a triple star system in the northern constellation of Cassiopeia. It is visible to the naked eye with a combined apparent visual magnitude of 4.49. With an annual parallax shift of 28.36±0.44 mas as seen from Earth's orbit, it is located approximately 115 light years away. The system is moving closer with a heliocentric radial velocity of −12.4 km/s.
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Cassiopeia |
Right ascension | 02h 01m 57.45035s |
Declination | +70° 54′ 25.2902″ |
Apparent magnitude (V) | 4.49 |
Characteristics | |
Spectral type | A3 Va (A2 V + F2 V) |
B−V color index | 0.164±0.008 |
Astrometry | |
Radial velocity (Rv) | −12.4 km/s |
Proper motion (μ) | RA: −55.69 mas/yr Dec.: −8.71 mas/yr |
Parallax (π) | 28.36 ± 0.44 mas |
Distance | 115 ± 2 ly (35.3 ± 0.5 pc) |
Absolute magnitude (MV) | 1.75 |
Orbit | |
Primary | 48 Cas A |
Companion | 48 Cas B |
Period (P) | 61.14±0.05 yr |
Semi-major axis (a) | 0.614±0.002″ |
Eccentricity (e) | 0.355±0.001 |
Inclination (i) | 16.7±0.9° |
Longitude of the node (Ω) | 48.2±3.2° |
Periastron epoch (T) | 1964.35±0.09 |
Argument of periastron (ω) (secondary) | 19.5±3.6° |
Details | |
48 Cas A | |
Mass | 1.93 M☉ |
Luminosity | 17.8+0.6 −1.2 L☉ |
Surface gravity (log g) | 4.47 cgs |
Temperature | 8,538±290 K |
Metallicity [Fe/H] | −0.4 dex |
Rotational velocity (v sin i) | 61 km/s |
Age | 376 Myr |
48 Cas B | |
Mass | 1.17 M☉ |
Other designations | |
Database references | |
SIMBAD | data |
The primary component, designated 48 Cassiopeiae A, is a white A-type main-sequence star with a stellar classification of A2 V and an apparent magnitude of +4.65. It has a companion, component B, which is an F-type main-sequence star of class F2 V and an apparent magnitude of +6.74. This pair orbit around their common centre of mass once every 61.1 years. They have a semimajor axis of 0.614 arcseconds and an eccentricity of 0.355. A third companion, component C, is a magnitude 13.20 star located at an angular separation of 23.16 arcseconds as of 2014, or at least 816.5 AU away.
48 Cassiopeiae also has the Bayer designation A Cassiopeiae, the only star with a Latin letter designation in the constellation.