Tau Virginis

Tau Virginis (τ Vir, τ Virginis) is a single^[13] star in the zodiac constellation Virgo. With an apparent visual magnitude of 4.28,^[2] it is faintly visible to the naked eye. The distance to Tau Virginis, based upon parallax measurements, is approximately 225 light years with a margin of error of ±3 light years.

τ Virginis

Location of τ Virginis (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Virgo
Right ascension	14h 01m 38.79341s[1]
Declination	+01° 32′ 40.3145″[1]
Apparent magnitude (V)	4.2777±0.0007[2]
Characteristics
Spectral type	A2IV/V[3]
U−B color index	+0.12[4]
B−V color index	+0.11[4]
Astrometry
Radial velocity (Rv)	−6.7±0.9[5] km/s
Proper motion (μ)	RA: +17.49[1] mas/yr Dec.: −21.27[1] mas/yr
Parallax (π)	14.50±0.18 mas[1]
Distance	225 ± 3 ly (69.0 ± 0.9 pc)
Absolute magnitude (MV)	+0.5[6]
Details
Mass	1.96[7] M☉
Radius	1.6[8] R☉
Luminosity	70[9] L☉
Surface gravity (log g)	3.39[7] cgs
Temperature	8,413±286[7] K
Metallicity [Fe/H]	−0.19[10] dex
Rotational velocity (v sin i)	186[11] km/s
Age	724[7] Myr
Other designations
τ Vir, 93 Virginis, BD+02°2761, FK5 516, HD 122408, HIP 68520, HR 5264, SAO 120238[12]
Database references
SIMBAD	data

This star has a stellar classification of A2IV/V,^[3] which matches the spectrum of an A-type main sequence star mixed with spectral traits of a subgiant. It is about 700^[7] million years old and is spinning rapidly with a projected rotational velocity of 186 km/s.^[11] The star has nearly double^[7] the mass of the Sun and about 160% of the Sun's radius.^[8] It shines with 70^[9] times the luminosity of the Sun and has an effective temperature of 8413 K in its outer atmosphere.^[7]

Tau Virginis has multiple visual companions, listed below:^[14]

Companion	Visual Magnitude	Angular Separation	Position Angle	Year Measured
B	9.41	82.70″	287°	2012
C	13.10	176.70″	353°	2000
D	9.68	342.70″	85°	2012
E	12.00	14.6″	175°	2009