Upsilon Piscium

Upsilon Piscium is a solitary,^[10] white-hued star in the zodiac constellation of Pisces. It is faintly visible to the naked eye, having an apparent visual magnitude of +4.75.^[2] Based upon an annual parallax shift of 10.59 mas as seen from Earth,^[1] it is located about 308 light years from the Sun. The star is drifting further away with a heliocentric radial velocity of +6 km/s.^[4]

Upsilon Piscium

Location of υ Piscium (circled)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Pisces
Right ascension	01h 19m 27.99289s[1]
Declination	+27° 15′ 50.6155″[1]
Apparent magnitude (V)	4.752[2]
Characteristics
Spectral type	A3 V[3]
U−B color index	+0.10[2]
B−V color index	+0.03[2]
Astrometry
Radial velocity (Rv)	+5.8±2.7[4] km/s
Proper motion (μ)	RA: +22.98[1] mas/yr Dec.: −11.12[1] mas/yr
Parallax (π)	10.59±0.25 mas[1]
Distance	308 ± 7 ly (94 ± 2 pc)
Absolute magnitude (MV)	−0.13[5]
Details
Mass	2.84±0.05[3] M☉
Radius	2.2[6] R☉
Luminosity	117[3] L☉
Surface gravity (log g)	3.59[7] cgs
Temperature	9,183±312[7] K
Metallicity [Fe/H]	+0.00±0.05[8] dex
Rotational velocity (v sin i)	91[3] km/s
Age	461[7] Myr
Other designations
υ Psc, 90 Piscium, BD+26°220, FK5 45, HD 7964, HIP 6193, HR 383, SAO 74637[9]
Database references
SIMBAD	data

This is an ordinary A-type main sequence star with a stellar classification of A3 V.^[3] It is 461^[7] million years old – about 98% of the way through its main sequence lifetime^[3] – and is spinning with a projected rotational velocity of 91 km/s.^[3] The star has 2.8^[3] times the mass of the Sun, about 2.2^[6] times the Sun's radius, and is radiating 117^[3] times the Sun's luminosity from its photosphere at an effective temperature of 9183 K.^[7]

Naming

υ Piscium is the Bayer designation for this star, which is Latinized as Upsilon Piscium. It has the Flamsteed designation 90 Piscium.^[9]

In Chinese, 奎宿 (Kuí Sù), meaning Legs (asterism), refers to an asterism composed of υ Piscium, η Andromedae, 65 Piscium, ζ Andromedae, ε Andromedae, δ Andromedae, π Andromedae, ν Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, φ Piscium, χ Piscium and ψ¹ Piscium. Consequently, the Chinese name for υ Piscium itself is 奎宿十三 (Kuí Sù shí sān, English: the Thirteenth Star of Legs.)^[11]