3 Persei

3 Persei is a single,^[7] orange-hued star in the northern constellation of Perseus. It is dimly visible to the naked eye under good viewing conditions, having an apparent visual magnitude of 5.70^[2] The star is located around 79 parsecs (257 ly) distant, based upon an annual parallax shift of 12.7 mas.

3 Persei

Observation data Epoch J2000      Equinox J2000
Constellation	Perseus
Right ascension	01h 58m 33.50596s[1]
Declination	+49° 12′ 15.6705″[1]
Apparent magnitude (V)	5.70[2]
Characteristics
Spectral type	K0 IV[3]
Astrometry
Radial velocity (Rv)	−0.67±0.17[4] km/s
Proper motion (μ)	RA: +7.051[1] mas/yr Dec.: +41.686[1] mas/yr
Parallax (π)	12.6940±0.0671 mas[1]
Distance	257 ± 1 ly (78.8 ± 0.4 pc)
Absolute magnitude (MV)	1.33[2]
Details[5]
Mass	1.41±0.17 M☉
Radius	8.27±0.55 R☉
Luminosity	37.2+7.5 −6.3 L☉
Surface gravity (log g)	2.72±0.09 cgs
Temperature	4,757±25 K
Metallicity [Fe/H]	−0.15±0.05 dex
Rotational velocity (v sin i)	1.85±0.45 km/s
Age	2.91±0.98 Gyr
Other designations
3 Per, BD+48°576, HD 11949, HIP 9222, HR 568, SAO 37665[6]
Database references
SIMBAD	data

This star has a stellar classification of K0 IV,^[3] suggesting it is a K-type subgiant – an evolved star that has used up its core hydrogen and is evolving to become a red giant. However, da Silva et al. (2015) categorized it as a giant star proper.^[8] At the age of around three billion years, it has an estimated 1.4 times the mass of the Sun and has expanded to move than 8 times the Sun's radius. It is radiating roughly 37 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,757 K.^[5]