HD 72659
| Observation data Epoch J2000.0 Equinox ICRS | |
|---|---|
| Constellation | Hydra |
| Right ascension | 08h 34m 03.18984s |
| Declination | −01° 34′ 05.5822″ |
| Apparent magnitude (V) | 7.46 |
| Characteristics | |
| Evolutionary stage | subgiant |
| Spectral type | G2V |
| B−V color index | +0.612±0.015 |
| Astrometry | |
| Radial velocity (Rv) | −18.203+0.024 −0.029 km/s |
| Proper motion (μ) | RA: −112.313(26) mas/yr Dec.: −96.386(18) mas/yr |
| Parallax (π) | 19.2582±0.0271 mas |
| Distance | 169.4 ± 0.2 ly (51.93 ± 0.07 pc) |
| Absolute magnitude (MV) | 3.98 |
| Details | |
| Mass | 1.033±0.025 M☉ |
| Radius | 1.36±0.06 R☉ |
| Luminosity | 2.16±0.01 L☉ |
| Surface gravity (log g) | 4.19±0.02 cgs |
| Temperature | 5,929±61 K |
| Metallicity [Fe/H] | −0.02±0.06 dex |
| Rotational velocity (v sin i) | 1.6±0.9 km/s |
| Age | 8±1 Gyr |
| Other designations | |
| BD−01°2075, HD 72659, HIP 42030, SAO 136045, 2MASS J08340320-0134056, Gaia DR2 3073443760538892032 | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HD 72659 is a star in the equatorial constellation of Hydra. With an apparent visual magnitude of 7.46, its yellow-hued star is too faint to be viewed with the naked eye. Parallax measurements provide a distance estimate of 169.4 light years from the Sun, and it has an absolute magnitude of 3.98. The star is drifting closer with a radial velocity of −18.2 km/s.
This is a Sun-like main sequence star with a stellar classification of G2V, indicating that it is generating energy through core hydrogen fusion. It is older than the Sun with an age of about seven billion years, and is spinning with a projected rotational velocity of 5.1 km/s. The star has 7% greater mass than the Sun and a 38% larger radius. It is radiating more than double the Sun's luminosity from its photosphere at an effective temperature of 5,956 K. The metallicity of the stellar atmosphere is similar to the Sun.
Planetary system
An extrasolar planet was discovered orbiting this star in 2003 via the Doppler method. This is a superjovian planet with an eccentric orbit, completing a lap around its host star every 9.9 years. In 2022, the inclination and true mass of HD 72659 b were measured via astrometry, along with the detection of a second substellar companion, likely a brown dwarf. The orbit of the brown dwarf lies in the so-called brown dwarf desert, regions with a deficit of brown dwarfs. The host star is very old and thus HD 72659 b and c can not be directly imaged, even with the most modern equipment such as the James Webb Space Telescope. The moderate eccentricity of planet b may be the result of Kozai-Lidov oscillations.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination (°) |
Radius |
|---|---|---|---|---|---|---|
| b | 3.0+2.6 −0.1 MJ |
4.607±0.039 | 9.72±0.03 | 0.239±0.001 | 78±40 | — |
| c | 19.4+0.8 −0.5 MJ |
21.5+0.5 −0.4 |
97.1+3.4 −2.5 |
0.114+0.002 −0.003 |
40±2 | — |
See also
References
- 1 2 3 4 5 6 7 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. XHIP record for this object at VizieR.
- 1 2 3 4 5 6 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.
- 1 2 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
- 1 2 3 4 5 Ruggieri, A.; Sozzetti, A.; Desidera, S.; Mesa, D.; Gratton, R.; Marzari, F.; Bonavita, M.; Biazzo, K.; D'Orazi, V.; Ginski, C.; Meyer, M.; Malavolta, L.; Pinamonti, M.; Barbato, D.; Lazzoni, C.; Lanza, A. F.; Mancini, L.; Naponiello, L.; Nardiello, D.; Zingales, T.; Rainer, M.; Scandariato, G.; Giacobbe, P.; Cosentino, R.; Fiorenzano, A.; Claudi, R. (2025). "The GAPS programme at TNG LXVIII. Characterization of the outer substellar companion around HD 72659 with a multitechnique approach". Monthly Notices of the Royal Astronomical Society. 542 (2): 1233–1247. arXiv:2507.19063. doi:10.1093/mnras/staf1251.
- 1 2 3 4 Bonfanti, A.; et al. (2015). "Revising the ages of planet-hosting stars". Astronomy and Astrophysics. 575. A18. arXiv:1411.4302. Bibcode:2015A&A...575A..18B. doi:10.1051/0004-6361/201424951. S2CID 54555839.
- ↑ "HD 72659". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-24.
- ↑ Luck, R. Earle (January 2017). "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants". The Astronomical Journal. 153 (1): 19. arXiv:1611.02897. Bibcode:2017AJ....153...21L. doi:10.3847/1538-3881/153/1/21. S2CID 119511744. 21.
- ↑ Butler, R. Paul; et al. (2003). "Seven New Keck Planets Orbiting G and K Dwarfs". The Astrophysical Journal. 582 (1): 455–466. Bibcode:2003ApJ...582..455B. doi:10.1086/344570. S2CID 17608922.
- ↑ Butler, R. P.; et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal. 646 (1): 505–522. arXiv:astro-ph/0607493. Bibcode:2006ApJ...646..505B. doi:10.1086/504701. hdl:2299/1103. S2CID 119067572.
- 1 2 3 Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.
