| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 13h 28m 25.8086s[1] |
| Declination | +13° 46′ 43.638″[1] |
| Apparent magnitude (V) | +4.97[2] |
| Characteristics | |
| Spectral type | G4 V-IV[3] |
| U−Bcolor index | 0.26 |
| B−Vcolor index | 0.714±0.007[2] |
| V−Rcolor index | 0.39 |
| R−Icolor index | 0.36 |
| Variable type | none |
| Astrometry | |
| Radial velocity (Rv) | 4.44±0.13[2] km/s |
| Proper motion (μ) | RA: −235.951(75)mas/yr[1] Dec.: −575.969(32)mas/yr[1] |
| Parallax (π) | 55.2511±0.0779 mas[1] |
| Distance | 59.03 ± 0.08 ly (18.10 ± 0.03 pc) |
| Absolute magnitude (MV) | +3.70±0.01[4] |
| Details | |
| Mass | 1.09±0.02[5] M☉ |
| Radius | 1.942±0.008[6] R☉ |
| Luminosity | 3.047±0.043[6] L☉ |
| Surface gravity (log g) | 3.94±0.08[6] cgs |
| Temperature | 5,473±32[6] K |
| Metallicity [Fe/H] | −0.06±0.01[6] dex |
| Rotational velocity (v sin i) | 1.56±0.50[5] km/s |
| Age | 7.77±0.51[5] Gyr |
| Other designations | |
| 70 Vir,BD+14°2621,GJ 512.1,GJ 9446,HD 117176,HIP 65721,HR 5072,SAO 100582,WDS 13284+1347A[7] | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| ARICNS | data |
70 Virginis is a binary[8]star located 59[1] light years from the Sun in theequatorialconstellation ofVirgo, near the northern constellation border withComa Berenices.70 Virginis is itsFlamsteed designation. The star is visible to the naked eye as a faint, yellow-hued point of light with anapparent visual magnitude of +4.97.[2] It is drifting further away with a heliocentricradial velocity of +4.4 km/s[2] and has a highproper motion, traversing thecelestial sphere at the rate of 0.621 arc seconds per annum.[9]
This object has astellar classification of G4 V-IV,[3] being rather unusually bright for amain sequence star of its type and thus may be just starting to evolve into thesubgiant phase. It is an estimated 7.9[10] billion years old and is spinning with aprojected rotational velocity of 4.8 km/s.[11] The star has 1.09[5] times themass of the Sun and 1.94 times theSun's radius. It is radiating 3.05 times theluminosity of the Sun from itsphotosphere at aneffective temperature of 5,473 K.[6] Themetallicity – a term astronomers use to describe the abundance of elements heavier than helium – is near solar.[10][6]
In 2011, a star was discovered 2.86 arcseconds away from the primary, and is likely associated with 70 Virginis. Based on its properties, it has a spectral type later than M5V, and has a mass of about 8% that of the Sun.[8] There is also an L-typebrown dwarf 42.7 arcseconds away from the primary, but it is unclear whether this is bound to the system.[8]
In 1996, 70 Virginis was discovered to have anextrasolar planet in orbit around it.[12] There is also an orbitingdusty disc with an average temperature of 153 K located at a mean distance of 3.4AU from the star.[13]
The discovery of the planet around 70 Virginis was announced on January 17, 1996 at the meeting of theAmerican Astronomical Society in San Antonio, Texas. The planet was detected usingradial velocity measurements taken with theC. Donald Shane telescope atLick Observatory. It has anorbital period of 117 days, aneccentricity of 0.4, and a mass at least 7.4 times that ofJupiter.[14][12]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >7.40±0.02 MJ | 0.481±0.003 | 116.6926±0.0014 | 0.399±0.002 | — | — |
| Dust disc | >3.4AU | — | — | |||
