HD 121504 is a star with an orbiting exoplanet in the southern constellation of Centaurus. It is located at a distance of 136 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of 19.6 km/s.[5] With an apparent visual magnitude of 7.54,[1] this star is too faint to be visible to the naked eye. It shows a high proper motion, traversing the celestial sphere at an angular rate of 0.270 arcsec yr−1.[8]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Centaurus[1] |
| Right ascension | 13h 57m 17.239s[2] |
| Declination | −56° 02′ 24.16″[2] |
| Apparent magnitude (V) | 7.54[1] |
| Characteristics | |
| Spectral type | G2V[3] |
| B−V color index | 0.593±0.002[4][1] |
| Astrometry | |
| Radial velocity (Rv) | 19.603±0.0004[5] km/s |
| Proper motion (μ) | RA: −249.354 mas/yr[2] Dec.: −84.570 mas/yr[2] |
| Parallax (π) | 24.0593 ± 0.0269 mas[2] |
| Distance | 135.6 ± 0.2 ly (41.56 ± 0.05 pc) |
| Absolute magnitude (MV) | 4.27[1] |
| Details | |
| Mass | 1.16±0.02[6] M☉ |
| Radius | 1.15±0.03[6] R☉ |
| Luminosity | 1.62±0.04[6] L☉ |
| Surface gravity (log g) | 4.38±0.03[6] cgs |
| Temperature | 6,089±47[6] K |
| Metallicity [Fe/H] | 0.16[4] dex |
| Rotation | 8.6 days[4] |
| Rotational velocity (v sin i) | 2.6[4] km/s |
| Age | 1.9±1.0[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
The spectrum of this star presents as an ordinary G-type main-sequence star, a yellow dwarf similar in appearance to the Sun, having a stellar classification of G2V.[3] It is roughly two billion years old and is spinning with a rotation period of 8.6 days. The star has 16% more mass than the Sun and a 15% greater radius.[6] The metallicity (the abundance of elements more massive than helium) is higher than solar.[4] The star is radiating 162% of the luminosity of the Sun from its photosphere at an effective temperature of 6,089 K.[6]
A nearby visual companion, designated as SAO 241323 has been proposed as a component of the system. However, the pair form an optical binary with an angular separation of 34.2″,[4] and in reality this is a white giant star located thousands of light years away.[citation needed]
Exoplanet
editIn 2000 the Geneva Extrasolar Planet Search Team announced the discovery of an extrasolar planet orbiting the star.[9]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >1.22 MJ | 0.33 | 63.33 ± 0.03 | 0.03 ± 0.01 | — | — |
See also
editReferences
edit- ^ a b c d e Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644
- ^ a b c d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b Houk, Nancy (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 1. Ann Arbor, Michigan: Department of Astronomy, University of Michigan. Bibcode:1978mcts.book.....H.
- ^ a b c d e f g Mayor, M.; et al. (2004). "The CORALIE survey for southern extra-solar planets XII. Orbital solutions for 16 extra-solar planets discovered with CORALIE". Astronomy and Astrophysics. 415 (1): 391–402. arXiv:astro-ph/0310316. Bibcode:2004A&A...415..391M. doi:10.1051/0004-6361:20034250. S2CID 5233877.
- ^ a b Soubiran, C.; et al. (2018). "Gaia Data Release 2. The catalogue of radial velocity standard stars". Astronomy and Astrophysics. 616: A7. arXiv:1804.09370. Bibcode:2018A&A...616A...7S. doi:10.1051/0004-6361/201832795. S2CID 52952408.
- ^ a b c d e f g h Bonfanti, A.; et al. (2016). "Age consistency between exoplanet hosts and field stars". Astronomy & Astrophysics. 585: 14. arXiv:1511.01744. Bibcode:2016A&A...585A...5B. doi:10.1051/0004-6361/201527297. S2CID 53971692. A5.
- ^ "HD 121504". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-04-03.
- ^ Luyten, W. J. (June 1995). "VizieR Online Data Catalog: NLTT Catalogue (Luyten, 1979)". VizieR Online Data Catalog. Bibcode:1995yCat.1098....0L.
- ^ "European Southern Observatory: Six Extrasolar Planets Discovered". SpaceRef Interactive Inc. 7 August 2000. Retrieved 15 August 2009.