HD 104304
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo | 
| Right ascension | 12h 00m 44.461s | 
| Declination | −10° 26′ 46.06″ | 
| Apparent magnitude (V) | 5.54 | 
| Characteristics | |
| Spectral type | G8 IV + M4V | 
| U−B color index | +0.43 | 
| B−V color index | +0.76 | 
| Astrometry | |
| Radial velocity (Rv) | 0.14±0.14 km/s | 
| Proper motion (μ) | RA: +82.841 mas/yr Dec.: −482.807 mas/yr | 
| Parallax (π) | 78.7565±0.1206 mas | 
| Distance | 41.41 ± 0.06 ly (12.70 ± 0.02 pc) | 
| Absolute magnitude (MV) | 5.15±0.009 | 
| Orbit | |
| Period (P) | 48.5 yr | 
| Semi-major axis (a) | 10.4 AU | 
| Eccentricity (e) | 0.29 | 
| Inclination (i) | 35° | 
| Details | |
| A | |
| Mass | 0.98 M☉ | 
| Radius | 1.01 R☉ | 
| Surface gravity (log g) | 4.43 cgs | 
| Temperature | 5,538 K | 
| Metallicity [Fe/H] | 0.18 dex | 
| Rotational velocity (v sin i) | 4.5 km/s | 
| Age | 8.48 Gyr | 
| B | |
| Mass | 0.21+0.03 −0.02 M☉ | 
| Other designations | |
| 24 G. Virginis, BD−09°3413, GJ 454, HD 104304, HIP 58576, HR 4587, SAO 157041, LTT 4476 | |
| Database references | |
| SIMBAD | data | 
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, 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. The primary component has a stellar classification of G8 IV, 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.
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. It is believed to have a mass of 0.21 M☉ and spectral type of M4V although the spectrum has not been directly observed. The most likely orbit has a period of 48.5 years and an eccentricity of 0.29. 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.