Omicron Virginis
Omicron Virginis (ο Vir, ο Virginis) is a star in the zodiac constellation of Virgo. It is visible to the naked eye with an apparent visual magnitude of +4.12. Based upon parallax measurements, it is about 163 light years from the Sun.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 12h 05m 12.54049s |
| Declination | +08° 43′ 58.7498″ |
| Apparent magnitude (V) | 4.12 |
| Characteristics | |
| Spectral type | G8 IIIa CN-1Ba1CH1 |
| Astrometry | |
| Radial velocity (Rv) | −29.62 km/s |
| Proper motion (μ) | RA: −218.69 mas/yr Dec.: +57.76 mas/yr |
| Parallax (π) | 19.98 ± 0.22 mas |
| Distance | 163 ± 2 ly (50.1 ± 0.6 pc) |
| Absolute magnitude (MV) | +0.52 |
| Details | |
| Mass | 2.17 M☉ |
| Radius | 9.62 R☉ |
| Luminosity | 57 L☉ |
| Surface gravity (log g) | 3.17 cgs |
| Temperature | 5,107 K |
| Metallicity [Fe/H] | −0.30 dex |
| Rotational velocity (v sin i) | 2.23 km/s |
| Age | 0.88 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
ο Virginis is a G-type giant star with a stellar classification of G8 IIIa CN-1Ba1CH1. This indicates that it is a Barium star. Typically Barium stars are close binaries with a white dwarf companion, but no companion has been detected for ο Virginis. It has been suggested that an excess SiIV emission flux is due to an unseen white dwarf companion.
ο Virginis is a giant star around ten times larger than the Sun. Although it is slightly cooler, it is radiating about 60-132 times the luminosity of the Sun. It is over twice as massive as the Sun and is around a billion years old. A simplified statistical analysis suggests that ο Virginis is likely to be a red giant branch star fusing hydrogen in a shell around an inert helium core, but there is about a 22% chance that it is a horizontal branch star fusing helium in its core.