Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Hydra |
Right ascension | 11h 34m 29.48628s[1] |
Declination | –32° 49′ 52.8199″[1] |
Apparent magnitude (V) | 5.97[2] + 15 |
Characteristics | |
Spectral type | K0 V[3] + DC8[4] |
U−B color index | 0.325[2] |
B−V color index | 0.80[2] |
V−R color index | 0.44 |
R−I color index | 0.40 |
Astrometry | |
Radial velocity (Rv) | –22.21[5] km/s |
Proper motion (μ) | RA: –670.120[1] mas/yr Dec.: +822.228[1] mas/yr |
Parallax (π) | 104.7828 ± 0.0518 mas[1] |
Distance | 31.13 ± 0.02 ly (9.544 ± 0.005 pc) |
Absolute magnitude (MV) | 6.05[6] |
Details | |
HR 4458 A | |
Radius | 0.84[7] R☉ |
Luminosity (bolometric) | 0.368[8] L☉ |
Surface gravity (log g) | 4.59[9] cgs |
Temperature | 5,241[9] K |
Metallicity [Fe/H] | –0.37[9] dex |
Rotational velocity (v sin i) | 6.79[10] km/s |
Age | 4.6–5.8[11] Gyr |
Other designations | |
WD 1132-325: VB 04 | |
Database references | |
SIMBAD | data |
ARICNS | data |
HR 4458 is a binary star system in the equatorial constellation of Hydra. It has the Gould designation 289 G. Hydrae; HR 4458 is the Bright Star Catalogue designation. At a distance of 31.13 light years, it is the closest star system to the Solar System within this constellation. This object is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.97.[2] It is moving closer to the Earth with a heliocentric radial velocity of −22 km/s.[5]
The primary component is K-type main-sequence star with a stellar classification of K0 V.[3] It is around five[11] billion years old with 84%[7] of the Sun's radius. The star is radiating 37%[8] of the Sun's luminosity from its photosphere at an effective temperature of 5,241 K.[9] It has been examined for the presence of an infrared excess, but none was detected.[8]
There is a common proper motion companion at an angular separation of 16.2″,[4] corresponding to a projected separation of 162.5 AU.[13] This is a white dwarf star with a classification of DC8.[4] The orbital period of the pair is estimated as 1,110 years.[13]