# HD 122430

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/HD_122430
> Markdown URL: https://mediated.wiki/source/HD_122430.md
> Source: https://en.wikipedia.org/wiki/HD_122430
> Source revision: 1339871060
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

Star in the constellation Hydra

HD 122430 Observation data Epoch J2000 Equinox J2000 Constellation Hydra[1] Right ascension 14h 02m 22.78173s[2] Declination −27° 25′ 47.1992″[2] Apparent magnitude (V) 5.47[1] Characteristics Spectral type K2–3III[3] B−V color index 1.331±0.003[1] Astrometry Radial velocity (Rv) −0.61±0.24[2] km/s Proper motion (μ) RA: −31.861±0.259[2] mas/yr Dec.: −4.195±0.215[2] mas/yr Parallax (π) 7.3651±0.1407 mas[2] Distance 443 ± 8 ly (136 ± 3 pc) Absolute magnitude (MV) −0.17[1] Details[4] Mass 1.62±0.19 M☉ Radius 21.20±2.06 R☉ Luminosity 189.6±4.2[2] 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 single [star](/source/Star)[6] in the [equatorial](/source/Celestial_equator) [constellation](/source/Constellation) of [Hydra](/source/Hydra_(constellation)). It has an orange hue and is faintly visible to the naked eye with an [apparent visual magnitude](/source/Apparent_visual_magnitude) of 5.47.[1] The star is located at a distance of 105.6 [light years](/source/Light_year) from the [Sun](/source/Sun) based on [parallax](/source/Stellar_parallax). It has the Bayer designation **h Hydrae**.[7]

This is an aging [giant star](/source/Giant_star) with a [stellar classification](/source/Stellar_classification) of K2–3III.[3] It has completely run out of the [hydrogen](/source/Hydrogen) [fuel](/source/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[2] times the [luminosity](/source/Luminosity) of the Sun from its [photosphere](/source/Photosphere) at an [effective temperature](/source/Effective_temperature) of 4300 K.[4]

A candidate [exoplanet](/source/Exoplanet) was reported orbiting the star via the [radial velocity method](/source/Radial_velocity_method) at a conference in 2003, and designated HD 122430 b. It has an [orbital period](/source/Orbital_period) of 0.94 years and an [eccentricity](/source/Orbital_eccentricity) of 0.68.[8] However, a follow-up study by Soto et al. (2015) failed to detect a signal, so it remains unconfirmed.[9]

The HD 122430 planetary system[8] 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 — —

## See also

- [HD 47536](/source/HD_47536)

- [List of extrasolar planets](/source/List_of_extrasolar_planets)

## References

1. ^ [***a***](#cite_ref-Anderson2012_1-0) [***b***](#cite_ref-Anderson2012_1-1) [***c***](#cite_ref-Anderson2012_1-2) [***d***](#cite_ref-Anderson2012_1-3) [***e***](#cite_ref-Anderson2012_1-4) Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". *[Astronomy Letters](/source/Astronomy_Letters)*. **38** (5): 331. [arXiv](/source/ArXiv_(identifier)):[1108.4971](https://arxiv.org/abs/1108.4971). [Bibcode](/source/Bibcode_(identifier)):[2012AstL...38..331A](https://ui.adsabs.harvard.edu/abs/2012AstL...38..331A). [doi](/source/Doi_(identifier)):[10.1134/S1063773712050015](https://doi.org/10.1134%2FS1063773712050015). [XHIP record for this object](https://vizier.cds.unistra.fr/viz-bin/VizieR-4?-ref=VIZ681510a8389ecb&-out.src=V%2F137D%2FXHIP&-nav=cat%3AV%2F137D%26tab%3A{V%2F137D%2FXHIP}%26key%3Asource%3DV%2F137D%2FXHIP%26HTTPPRM%3A&-source=V%2F137D%2FXHIP&-out=HIP&HIP=68581&-out=Comp&-out=Gr&-out=RAJ2000&-out=DEJ2000&-out=Dist&-out=X&-out=Y&-out=Z&-out=SpType&-out=Simbad&-out=Hpmag&-out=Lum&-out=Cst) at [VizieR](/source/VizieR).

1. ^ [***a***](#cite_ref-GaiaDR2_2-0) [***b***](#cite_ref-GaiaDR2_2-1) [***c***](#cite_ref-GaiaDR2_2-2) [***d***](#cite_ref-GaiaDR2_2-3) [***e***](#cite_ref-GaiaDR2_2-4) [***f***](#cite_ref-GaiaDR2_2-5) [***g***](#cite_ref-GaiaDR2_2-6) [***h***](#cite_ref-GaiaDR2_2-7) [Brown, A. G. A.](/source/Anthony_Brown_(scientist)); et al. ([Gaia collaboration](/source/Data_Processing_and_Analysis_Consortium)) (August 2018). ["*Gaia* Data Release 2: Summary of the contents and survey properties"](https://doi.org/10.1051%2F0004-6361%2F201833051). *[Astronomy & Astrophysics](/source/Astronomy_%26_Astrophysics)*. **616**. A1. [arXiv](/source/ArXiv_(identifier)):[1804.09365](https://arxiv.org/abs/1804.09365). [Bibcode](/source/Bibcode_(identifier)):[2018A&A...616A...1G](https://ui.adsabs.harvard.edu/abs/2018A&A...616A...1G). [doi](/source/Doi_(identifier)):[10.1051/0004-6361/201833051](https://doi.org/10.1051%2F0004-6361%2F201833051). [Gaia DR2 record for this source](https://vizier.u-strasbg.fr/viz-bin/VizieR-S?Gaia%20DR2%206177432396478424576) at [VizieR](/source/VizieR).

1. ^ [***a***](#cite_ref-houk1979_3-0) [***b***](#cite_ref-houk1979_3-1) Houk, Nancy (1979). *Michigan catalogue of two-dimensional spectral types for the HD stars*. Vol. 3. Ann Arbor, Michigan: Department of Astronomy, University of Michigan. [Bibcode](/source/Bibcode_(identifier)):[1982mcts.book.....H](https://ui.adsabs.harvard.edu/abs/1982mcts.book.....H).

1. ^ [***a***](#cite_ref-Jofré2015_4-0) [***b***](#cite_ref-Jofré2015_4-1) [***c***](#cite_ref-Jofré2015_4-2) [***d***](#cite_ref-Jofré2015_4-3) Jofré, E.; et al. (2015). "Stellar parameters and chemical abundances of 223 evolved stars with and without planets". *Astronomy & Astrophysics*. **574**: A50. [arXiv](/source/ArXiv_(identifier)):[1410.6422](https://arxiv.org/abs/1410.6422). [Bibcode](/source/Bibcode_(identifier)):[2015A&A...574A..50J](https://ui.adsabs.harvard.edu/abs/2015A&A...574A..50J). [doi](/source/Doi_(identifier)):[10.1051/0004-6361/201424474](https://doi.org/10.1051%2F0004-6361%2F201424474). [S2CID](/source/S2CID_(identifier)) [53666931](https://api.semanticscholar.org/CorpusID:53666931).

1. **[^](#cite_ref-SIMBAD_5-0)** ["HD 117207"](http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+117207). *[SIMBAD](/source/SIMBAD)*. [Centre de données astronomiques de Strasbourg](/source/Centre_de_donn%C3%A9es_astronomiques_de_Strasbourg). Retrieved 2018-07-23.

1. **[^](#cite_ref-Eggleton2008_6-0)** Eggleton, P. P.; Tokovinin, A. A. (September 2008). ["A catalogue of multiplicity among bright stellar systems"](https://doi.org/10.1111%2Fj.1365-2966.2008.13596.x). *Monthly Notices of the Royal Astronomical Society*. **389** (2): 869–879. [arXiv](/source/ArXiv_(identifier)):[0806.2878](https://arxiv.org/abs/0806.2878). [Bibcode](/source/Bibcode_(identifier)):[2008MNRAS.389..869E](https://ui.adsabs.harvard.edu/abs/2008MNRAS.389..869E). [doi](/source/Doi_(identifier)):[10.1111/j.1365-2966.2008.13596.x](https://doi.org/10.1111%2Fj.1365-2966.2008.13596.x). [S2CID](/source/S2CID_(identifier)) [14878976](https://api.semanticscholar.org/CorpusID:14878976).

1. **[^](#cite_ref-Wagman2003_7-0)** Morton Wagman (2003). [*Lost Stars: Lost, Missing, and Troublesome Stars from the Catalogues of Johannes Bayer, Nicholas-Louis de Lacaille, John Flamsteed, and Sundry Others*](https://books.google.com/books?id=TYLvAAAAMAAJ) (2 ed.). McDonald & Woodward Publishing Company. [ISBN](/source/ISBN_(identifier)) [978-0-939923-78-6](https://en.wikipedia.org/wiki/Special:BookSources/978-0-939923-78-6). [OCLC](/source/OCLC_(identifier)) [1131243914](https://search.worldcat.org/oclc/1131243914).

1. ^ [***a***](#cite_ref-Setiawan2003_8-0) [***b***](#cite_ref-Setiawan2003_8-1) Setiawan, J. (October 2003). *Planets around evolved stars*. Proceedings of the Conference on Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets, 22–25 April 2003, Heidelberg, Germany. Vol. 539. Noordwijk, Netherlands: ESA Publications Division. pp. 595–598. [Bibcode](/source/Bibcode_(identifier)):[2003ESASP.539..595S](https://ui.adsabs.harvard.edu/abs/2003ESASP.539..595S). [ISBN](/source/ISBN_(identifier)) [92-9092-849-2](https://en.wikipedia.org/wiki/Special:BookSources/92-9092-849-2).

1. **[^](#cite_ref-Soto2015_9-0)** Soto, M. G.; et al. (August 2015). ["RAFT - I. Discovery of new planetary candidates and updated orbits from archival FEROS spectra"](https://doi.org/10.1093%2Fmnras%2Fstv1144). *Monthly Notices of the Royal Astronomical Society*. **451** (3): 3131–3144. [arXiv](/source/ArXiv_(identifier)):[1505.04796](https://arxiv.org/abs/1505.04796). [Bibcode](/source/Bibcode_(identifier)):[2015MNRAS.451.3131S](https://ui.adsabs.harvard.edu/abs/2015MNRAS.451.3131S). [doi](/source/Doi_(identifier)):[10.1093/mnras/stv1144](https://doi.org/10.1093%2Fmnras%2Fstv1144).

v t e Constellation of Hydra List of stars in Hydra Hydra in Chinese astronomy Stars Bayer α (Alphard) β γ (Naga) δ ε (Ashlesha) ζ η θ ι (Ukdah) κ λ μ ν ξ ο π ρ σ (Minchir) τ1 τ2 υ1 (Zhang) υ2 φ1 φ2 φ3 χ1 χ2 ψ ω b1 b3 C F Flamsteed 1 2 3 6 (a) 9 10 12 (D) 14 15 17 19 20 21 23 24 25 26 27 (P) 28 29 33 (A) 34 37 44 47 48 50 51 (k) 52 (l) 54 (m) 55 56 57 58 (Solitaire) 59 60 10 Crt 17 Crt 20 Crt 2 Sex Variable R U V W TW EX HS KU LQ V361 V419 V421 V478 V484 HR 3378 3538 3749 (G) 3750 3858 (I) 3862 3919 3923 (Felis) 4162 4328 4339 (β Ant) 4445 5265 HD 72659 74156 82943 86226 86264 90156 (γ Ant) Other 2MASS 1114−2618 ESO 439-26 Gliese 328 Gliese 357 Gliese 433 Gliese 453 GJ 3634 HAT-P-30 HE 1256−2738 HE 1327−2326 LHS 2065 LHS 3003 LTT 3780 SDSS J090745.0+024507 WASP-25 WASP-36 WASP-84 WASP-166 (Filetdor) WISE 0855−0714 WISEA J1141−3326 Exoplanets Gliese 357 d HD 72659 b HD 74156 b c HD 82943 b c HD 86226 b HD 86264 b TW Hydrae b (unconfirmed) WASP-193b Star clusters Messier 48 Messier 68 NGC 5694 Price-Whelan 1 Nebulae Abell 33 Abell 35 NGC 3242 Southern Owl Nebula Galaxies Messier 83 NGC 2617 2642 2697 2708 2758 2835 2848 2865 2890 2935 2936 2937 2960 2962 2986 2992 3030 3052 3054 3081 3109 3124 3200 3285 3285B 3290 3305 3307 3308 3309 3311 3312 3313 3314 3315 3316 3336 3369 3383 3393 3402 3463 3464 3585 3621 3673 3717 3904 3923 3936 4980 4993 5042 5061 5078 5085 5101 5135 5260 5264 5495 5626 Other 3C 196.1 AM 1316−241 Arp 7 CTQ 327 ESO 510-G13 GAMA202627 GLEAM J0917−0012 Hydra A IC 535 MRC 1138−262 Peekaboo Galaxy PKS 1151−348 RX J0911.4+0551 SDSS J0841+0101 TN J0924−2201 Tololo 1247−232 ZwCl 1693 BCG Galaxy clusters Abell 754 Abell 3411 Abell 3412 Bullet Group Hickson 40 Astronomical events GW170817 Category

---
Adapted from the Wikipedia article [HD 122430](https://en.wikipedia.org/wiki/HD_122430) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/HD_122430?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.