| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hydra |
| Right ascension | 14h 02m 22.78173s[1] |
| Declination | −27° 25′ 47.1992″[1] |
| Apparent magnitude (V) | 5.47[2] |
| Characteristics | |
| Spectral type | K2–3III[3] |
| B−Vcolor index | 1.331±0.003[2] |
| Astrometry | |
| Radial velocity (Rv) | −0.61±0.24[1] km/s |
| Proper motion (μ) | RA: −31.861±0.259[1]mas/yr Dec.: −4.195±0.215[1]mas/yr |
| Parallax (π) | 7.3651±0.1407 mas[1] |
| Distance | 443 ± 8 ly (136 ± 3 pc) |
| Absolute magnitude (MV) | −0.17[2] |
| Details[4] | |
| Mass | 1.62±0.19 M☉ |
| Radius | 21.20±2.06 R☉ |
| Luminosity | 189.6±4.2[1] L☉ |
| Surface gravity (log g) | 1.96±0.07 cgs |
| Temperature | 4,383±19 K |
| Metallicity[Fe/H] | −0.08±0.04 dex |
| Rotational velocity (v sin i) | 2.59±0.45 km/s |
| Age | 1.98±0.67 Gyr |
| Other designations | |
| CD−26° 10060,GC 18954,HD 122430,HIP 68581,HR 5265,SAO 182182,GCRV 8247[5] | |
| Database references | |
| SIMBAD | data |
HD 122430 is singlestar[6] in theequatorialconstellation ofHydra. It has an orange hue and is faintly visible to the naked eye with anapparent visual magnitude of 5.47.[2] The star is located at a distance of 105.6 light years from theSun based onparallax. It has the Bayer designationh Hydrae.[7]
This is an aginggiant star with astellar classification of K2–3III.[3] It has completely run out of thehydrogenfuel that keeps it stable, although it is only two billion years old,[4] younger than the Sun's 4.6 billion years. HD 122430 has a mass of 1.6 times and radius of 22.9 times that of the Sun.[4] Despite its younger age, it has slightly lower metallicity, approximately 90%. It is radiating 190[1] times theluminosity of the Sun from itsphotosphere at aneffective temperature of 4300 K.[4]
A candidateexoplanet was reported orbiting the star via theradial velocity method at a conference in 2003, and designated HD 122430 b. It has anorbital period of 0.94 years and aneccentricity of 0.68.[8] However, a follow-up study by Soto et al. (2015) failed to detect a signal, so it remains unconfirmed.[9]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b(unconfirmed) | >3.71MJ | 1.02 | 344.95±1.08 | 0.68±0.09 | — | — |
