Tau Virginis
Tau Virginis (τ Vir, τ Virginis) is a single star in the zodiac constellation Virgo. With an apparent visual magnitude of 4.28, 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.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 14h 01m 38.79341s |
| Declination | +01° 32′ 40.3145″ |
| Apparent magnitude (V) | 4.2777±0.0007 |
| Characteristics | |
| Spectral type | A2IV/V |
| U−B color index | +0.12 |
| B−V color index | +0.11 |
| Astrometry | |
| Radial velocity (Rv) | −6.7±0.9 km/s |
| Proper motion (μ) | RA: +17.49 mas/yr Dec.: −21.27 mas/yr |
| Parallax (π) | 14.50 ± 0.18 mas |
| Distance | 225 ± 3 ly (69.0 ± 0.9 pc) |
| Absolute magnitude (MV) | +0.5 |
| Details | |
| Mass | 1.96 M☉ |
| Radius | 1.6 R☉ |
| Luminosity | 70 L☉ |
| Surface gravity (log g) | 3.39 cgs |
| Temperature | 8,413±286 K |
| Metallicity [Fe/H] | −0.19 dex |
| Rotational velocity (v sin i) | 186 km/s |
| Age | 724 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This star has a stellar classification of A2IV/V, which matches the spectrum of an A-type main sequence star mixed with spectral traits of a subgiant. It is about 700 million years old and is spinning rapidly with a projected rotational velocity of 186 km/s. The star has nearly double the mass of the Sun and about 160% of the Sun's radius. It shines with 70 times the luminosity of the Sun and has an effective temperature of 8413 K in its outer atmosphere.
Tau Virginis has multiple visual companions, listed below:
| 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 |