HD 122430

HD 122430
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−V color 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]
Distance443 ± 8 ly
(136 ± 3 pc)
Absolute magnitude (MV)−0.17[2]
Details[4]
Mass1.62±0.19 M
Radius21.20±2.06 R
Luminosity189.6±4.2[1] L
Surface gravity (log g)1.96±0.07 cgs
Temperature4,383±19 K
Metallicity [Fe/H]−0.08±0.04 dex
Rotational velocity (v sin i)2.59±0.45 km/s
Age1.98±0.67 Gyr
Other designations
CD−26° 10060, GC 18954, HD 122430, HIP 68581, HR 5265, SAO 182182, GCRV 8247[5]
Database references
SIMBADdata

HD 122430 is single star[6] in the equatorial constellation of Hydra. It has an orange hue and is faintly visible to the naked eye with an apparent visual magnitude of 5.47.[2] The star is located at a distance of 105.6 light years from the Sun based on parallax.

This is an aging giant star with a stellar classification of K2–3III.[3] It has completely run out of the hydrogen fuel 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 the luminosity of the Sun from its photosphere at an effective temperature of 4300 K.[4]

A candidate exoplanet was reported orbiting the star via the radial velocity method at a conference in 2003, and designated HD 122430 b. It has an orbital period of 0.94 years and an eccentricity of 0.68.[7] However, a follow-up study by Soto et al. (2015) failed to detect a signal, so it remains unconfirmed.[8]

The HD 122430 planetary system[7]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b (unconfirmed) >3.71 MJ 1.02 344.95±1.08 0.68±0.09
  1. ^ a b c d e f g h Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1979 was invoked but never defined (see the help page).
  4. ^ a b c d Cite error: The named reference Jofré2015 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Setiawan2003 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Soto2015 was invoked but never defined (see the help page).