Phi Cassiopeiae

φ Cassiopeiae
Location of φ Cassiopeiae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cassiopeia
A
Right ascension 01h 20m 04.916s
Declination +58° 13 53.81
Apparent magnitude (V) +5.11
C
Right ascension 01h 19m 51.736s
Declination +58° 11 29.32
Apparent magnitude (V) +7.08
Characteristics
A
Spectral type F0Ia
U−B color index +0.49
B−V color index +0.68
C
Spectral type B6Ib
U−B color index 0.37
B−V color index +0.41
Astrometry
A
Radial velocity (Rv)−28.39 km/s
Proper motion (μ) RA: −1.479 mas/yr
Dec.: −1.231 mas/yr
Parallax (π)0.2142±0.0838 mas
Distanceapprox. 15,000 ly
(approx. 5,000 pc)
Absolute magnitude (MV)−8.76
C
Radial velocity (Rv)−28.50 km/s
Proper motion (μ) RA: −1.560 mas/yr
Dec.: −0.809 mas/yr
Parallax (π)0.3679 ± 0.0169 mas
Distance8,900 ± 400 ly
(2,700 ± 100 pc)
Absolute magnitude (MV)−6.5
Details
A
Mass6.3–17 M
Radius263 R
Luminosity170,000 L
Surface gravity (log g)1.0 cgs
Temperature7,341 K
Metallicity-0.24
Rotational velocity (v sin i)23 km/s
Age20 Myr
C
Mass21 M
Radius53 R
Luminosity83,000 L
Surface gravity (log g)2.05 cgs
Temperature15,500 K
Rotational velocity (v sin i)35 km/s
Other designations
34 Cassiopeiae, HR 382, CCDM J01200+5813, ADS 1073
A: HD 7927, HIP 6242, BD+57°260, SAO 22191, GC 1594
C: HD 7902, HIP 6229, BD+57°257, SAO 22187, GC 1590, NSV 466
Database references
SIMBADdata

Phi Cassiopeiae (φ Cas, φ Cassiopeiae) is a multiple star in the constellation Cassiopeia with a combined apparent magnitude of +4.95. The two brightest components are A and C, sometimes called φ1 and φ2 Cas. φ Cas A is an F0 bright supergiant of magnitude 4.95 and φ Cas C is a 7.08 magnitude B6 supergiant at 134".