Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Virgo |
Right ascension | 13h 09m 56.99067s[1] |
Declination | −05° 32′ 20.4185″[1] |
Apparent magnitude (V) | 4.37[2] (4.49 + 6.83 + 9.4 + 10.4)[3] |
Characteristics | |
Spectral type | A1Vs[4] + ? + A9m + ?[3] |
U−B color index | +0.00[2] |
B−V color index | −0.02[2] |
Astrometry | |
Radial velocity (Rv) | −2.9[5] km/s |
Proper motion (μ) | RA: −36.28[1] mas/yr Dec.: −31.22[1] mas/yr |
Parallax (π) | 10.33 ± 1.09 mas[1] |
Distance | approx. 320 ly (approx. 100 pc) |
Absolute magnitude (MV) | −0.52[6] |
Details | |
θ Vir Aa | |
Mass | 3.11±0.11[7] M☉ |
Luminosity | 190[7] L☉ |
Surface gravity (log g) | 3.4[4] cgs |
Temperature | 9,250[4] K |
Rotational velocity (v sin i) | 4±1[4] km/s |
Other designations | |
Database references | |
SIMBAD | data |
Theta Virginis (θ Vir, θ Virginis) is a multiple star system in the zodiac constellation of Virgo. Based upon parallax measurements, it is about 320 light years from the Sun. The three[9] stars in this system have a combined apparent visual magnitude of 4.37,[2] bright enough to be seen with the naked eye.
The primary component, Theta Virginis Aa, is a white-hued A-type main sequence star with a stellar classification of A1Vs.[4] It is part of a spectroscopic binary[10] whose components, Aa and Ab, have visual magnitudes of +4.49 and +6.83 respectively. The system has an orbital period of about 33.04 years with an eccentricity of 0.9.[3] The brighter member of this pair shows photometric and radial velocity periodicities with a cycle time of 0.7 days, which may indicate its rotation period.[11]
The inner pair is orbited by the 9.4 magnitude B component, at an angular separation of 7.1 arcseconds. A fourth component C, 69.6 arcseconds away, has an apparent magnitude of 10.4.[3] However, component C is an optical companion: it is physically unrelated and only appears close in the sky.[9]