T Persei

A visual band light curve For T Persei, plotted from AAVSO data [1]
Observation data Epoch J2000       Equinox J2000
Constellation	Perseus
Right ascension	2h 19m 21.87717s [2]
Declination	+58° 57′ 40.3455″ [2]
Apparent magnitude (V)	8.34-9.70 [3]
Characteristics
Spectral type	M2Iab [4]
U−B color index	+2.62 [5]
B−V color index	+2.33 [5]
Variable type	SRc [3]
Astrometry
Radial velocity (Rv)	−40.85 [6] km/s
Proper motion (μ)	RA: −1.237 [2]  mas/ yr Dec.: −0.186 [2]  mas/ yr
Parallax (π)	0.4119 ± 0.0237  mas [2]
Distance	2345±55 [7]  pc
Absolute magnitude (MV)	−6.90±0.07 [7]
Details [7]
Mass	9-12  M☉
Radius	510±20  R☉
Luminosity	45,700+4,400 −4,000  L☉
Surface gravity (log g)	0.06±0.05  cgs
Temperature	3,750±60  K
Metallicity [Fe/H]	−0.35  dex
Other designations
T Per, HD 14142, HIP 10829, BD+58°439, WDS J02194+5858, 2MASS J02192186+5857403, AAVSO 0212+58
Database references
SIMBAD	data

T Persei is a red supergiant located in the constellation Perseus. It varies in brightness between magnitudes 8.3 and 9.7 and is considered to be a member of the Double Cluster.

T Persei is a member of the Perseus OB1 association around the h and χ Persei open clusters, around 2 degrees north of the centre of the clusters. It is generally treated as an outlying member of the clusters. ^[8] It lies half a degree away from S Persei, another red supergiant Double Cluster member.

T Per is a semiregular variable star, whose brightness varies from magnitude 8.34 to 9.7 over a period of 2,430 days. ^[3] Unlike many red supergiants, it does not appear to have a long secondary period. ^{[4] [9]} It is relatively inactive for the red supergiant star, with low mass loss rate 8×10⁻⁶  Solar_mass/year and no detectable dust shell. ^[10]

The Washington Double Star Catalog lists T Persei as having a 9th magnitude companion 0.1  arc-seconds away. This is derived from Hipparcos measurements. However, no other sources report a companion. ^[11]

References