S Persei

variable star in the constellation Perseus

S Persei is a red supergiant located near the Double Cluster in Perseus, north of the cluster NGC 869.

S Persei
Location of S Persei (circled) near the Double Cluster (north is left)
Observation data
Epoch J2000      Equinox J2000
Constellation Perseus
Right ascension  2h 22m 51.70928s
Declination 58° 31′ 11.4476″
Apparent magnitude (V) 9.23 (7.9 - 12.0)
Characteristics
Spectral type M4.5I (M3Iae - M7)
B−V color index 2.65
Variable type SRc
Astrometry
Radial velocity (Rv)-39.71 km/s
Proper motion (μ) RA: −0.49 ± 0.23 mas/yr
Dec.: −1.19 ± 0.20 mas/yr
Parallax (π)0.413 ± 0.017 mas
Distance7,900 ± 300 ly
(2,420 ± 100 pc)
Absolute magnitude (MV)−6.36 (at mV 9.23)
Details
Mass20 M
Radius1,212 ± 124, 780 - 1,230 R
Luminosity86,000 - 186,000 L
Surface gravity (log g)0.0 cgs
Temperature3,000–3,600 K
Other designations
S Per, HD 14528, HIP 11093, BD+57°552, SAO 23261, WDS J02229+5835, AAVSO 0215+58
Database references
SIMBADdata

References change