HD 104304
Binary star in the constellation Virgo
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HD 104304 (24 G. Virginis) is a binary star system in the zodiac constellation Virgo. It has a combined apparent visual magnitude of 5.54,[3] making it visible to the unaided eye under suitable viewing conditions. The system is located at a distance of 41 light-years from the Sun based on parallax measurements.[2] The primary component has a stellar classification of G8 IV,[4] which means that this is a subgiant star that has left the main sequence and has begun to evolve into a giant star. The secondary is a faint red dwarf star with a class of M4V.[5]
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Virgo[1] |
| Right ascension | 12h 00m 44.461s[2] |
| Declination | −10° 26′ 46.06″[2] |
| Apparent magnitude (V) | 5.54[3] |
| Characteristics | |
| Spectral type | G8 IV[4] + M4V[5] |
| U−B color index | +0.43[3] |
| B−V color index | +0.76[3] |
| Astrometry | |
| Radial velocity (Rv) | 0.14±0.14[2] km/s |
| Proper motion (μ) | RA: +82.841 mas/yr[2] Dec.: −482.807 mas/yr[2] |
| Parallax (π) | 78.7565±0.1206 mas[2] |
| Distance | 41.41 ± 0.06 ly (12.70 ± 0.02 pc) |
| Absolute magnitude (MV) | 5.15±0.009[6] |
| Orbit[7] | |
| Period (P) | 92.9+4.8 −4.2 yr |
| Semi-major axis (a) | 22.85+0.87 −0.79 AU |
| Eccentricity (e) | 0.400±0.025 |
| Inclination (i) | 25.93+0.68 −0.58° |
| Details | |
| A | |
| Mass | 1.061±0.053[7] M☉ |
| Radius | 1.01[8] R☉ |
| Surface gravity (log g) | 4.43[8] cgs |
| Temperature | 5,538[4] K |
| Metallicity [Fe/H] | 0.18[9] dex |
| Rotational velocity (v sin i) | 4.5[10] km/s |
| Age | 8.48[8] Gyr |
| B | |
| Mass | 0.321+0.014 −0.013[7] M☉ |
| Other designations | |
| 24 G. Virginis, BD−09°3413, GJ 454, HD 104304, HIP 58576, HR 4587, SAO 157041, LTT 4476[11] | |
| Database references | |
| SIMBAD | data |
In 2007, a candidate planet was announced orbiting the primary. This was updated in 2010 when two independent papers announced the discovery of a common proper motion companion red dwarf.[5][12] It has a mass of 0.321 M☉[7] and spectral type of M4V although the spectrum has not been directly observed. The components orbit around the center of mass with a period of 92.9 years and an eccentricity of 0.400.[7] Further measurement will be needed to determine whether the star has a planetary companion, but further companions with masses above 83 MJ and separated by at least 3.9 au can be ruled out.[5]