HD 164509 is a binary star system in the constellation of Ophiuchus.[1] The primary component has an orbiting exoplanet companion.[6] This system is located at a distance of 175 light years based on parallax measurements,[2] and is drifting further away with a radial velocity of 13.7 km/s.[5] It has an absolute magnitude of 4.64,[6] but at that distance the system has an apparent visual magnitude of 8.10,[1] which is too faint to be seen with the naked eye.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ophiuchus[1] |
| Right ascension | 18h 01m 31.228s[2] |
| Declination | 00° 06′ 16.40″[2] |
| Apparent magnitude (V) | 8.10[1] |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | G2V[3] + M6.5V[4] |
| B−V color index | 0.665±0.018[2] |
| J−H color index | 0.28[2] |
| J−K color index | 0.36[2] |
| Astrometry | |
| Radial velocity (Rv) | 13.68±0.16[5] km/s |
| Proper motion (μ) | RA: −7.876 mas/yr[2] Dec.: −20.462 mas/yr[2] |
| Parallax (π) | 18.6155 ± 0.0219 mas[2] |
| Distance | 175.2 ± 0.2 ly (53.72 ± 0.06 pc) |
| Absolute magnitude (MV) | 4.64[6] |
| Orbit[7] | |
| Primary | HD 164509 A |
| Companion | HD 164509 B |
| Period (P) | ∼180 yr |
| Semi-major axis (a) | 36.5 ±1.9 au |
| Eccentricity (e) | 0.87 ±0.21 |
| Details | |
| HD 164509 A | |
| Mass | 1.103±0.004[8] M☉ |
| Radius | 1.041±0.003[8] R☉ |
| Luminosity | 1.150±0.001[8] L☉ |
| Surface gravity (log g) | 4.44±0.01[8] cgs |
| Temperature | 5,865±7[8] K |
| Metallicity [Fe/H] | 0.21[9] dex |
| Rotational velocity (v sin i) | 2.4±0.5[6] km/s |
| Age | 1.5±0.2[8] Gyr |
| HD 164509 B | |
| Mass | 0.45±0.01[4] M☉ |
| Temperature | 2,710[4] K |
| Other designations | |
| Database references | |
| SIMBAD | 164509 data |
The primary component is a Sun-like G-type main-sequence star[6] with a stellar classification of G2V.[3] It is young and metal rich, having heavy elements abundance 160% of solar.[9] The star has a modest level of magnetic activity in its chromosphere.[6] It has 1.10 times the mass of the Sun and 1.04 times the Sun's radius.[8] This star is radiating 1.15[8] times the luminosity of the Sun from its photosphere at an effective temperature of 5,865 K.[8]
Initially it was thought the system consisted of a single star, but in 2016 it was discovered the primary is accompanied by the M-class red dwarf star at a projected separation of 36.5±1.9 AU.[7] The evidence for this stellar companion being on a bound orbit was further fortified in 2017.[11][4]
Planetary system
edit
In 2011, a gas giant, HD 164509 Ab, was discovered orbiting the primary of HD 164509 using Doppler spectroscopy.[6] Given the binary nature of this system, the planet HD 164509 Ab could not have formed on the current orbit, which is unstable in long term.[12] Instead, it may be a captured body formed elsewhere.[13]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| Ab | 0.48±0.09 MJ | 0.875±0.008 | 282.4±3.8 | 0.26±0.14 | — | — |
References
edit- ^ a b c d 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 e f g h 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, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
- ^ a b c d Gonzales, Erica J.; et al. (April 2020), "The TRENDS High-contrast Imaging Survey. VIII. Compendium of Benchmark Objects", The Astrophysical Journal, 893 (1): 27, arXiv:2010.11866, Bibcode:2020ApJ...893...27G, doi:10.3847/1538-4357/ab71fb, S2CID 216296289, 27
- ^ 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 Giguere, Matthew J.; et al. (2012). "A High-Eccentricity Component in the Double-Planet System Around Hd 163607 and a Planet Around Hd 164509". The Astrophysical Journal. 744 (1): 4. arXiv:1109.2955. Bibcode:2012ApJ...744....4G. doi:10.1088/0004-637X/744/1/4. S2CID 119207947.
- ^ a b Wittrock, Justin M.; et al. (2016). "Stellar Companions to the Exoplanet Host Stars HD 2638 and HD 164509". The Astronomical Journal. 152 (5): 149. arXiv:1609.00016. Bibcode:2016AJ....152..149W. doi:10.3847/0004-6256/152/5/149. S2CID 45942803.
- ^ a b c d e f g h i Bonfanti, A.; Ortolani, S.; Piotto, G.; Nascimbeni, V. (2015). "Revising the ages of planet-hosting stars". Astronomy & Astrophysics. 575: A18. arXiv:1411.4302. Bibcode:2015A&A...575A..18B. doi:10.1051/0004-6361/201424951. S2CID 54555839.
- ^ a b Bryan, Marta L.; et al. (April 2016). "Statistics of Long Period Gas Giant Planets in Known Planetary Systems". The Astrophysical Journal. 821 (2): 89. arXiv:1601.07595. Bibcode:2016ApJ...821...89B. doi:10.3847/0004-637X/821/2/89. 89.
- ^ "HD 164509". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-12-27.
- ^ Ngo, Henry; et al. (2017). "No Difference in Orbital Parameters of RV-detected Giant Planets between 0.1 and 5 au in Single versus Multi-stellar Systems". The Astronomical Journal. 153 (6): 242. arXiv:1704.02326. Bibcode:2017AJ....153..242N. doi:10.3847/1538-3881/aa6cac. S2CID 119106164.
- ^ Quarles, Billy; Li, Gongjie; Kostov, Veselin; Haghighipour, Nader (2020). "Orbital Stability of Circumstellar Planets in Binary Systems". The Astronomical Journal. 159 (3): 80. arXiv:1912.11019. Bibcode:2020AJ....159...80Q. doi:10.3847/1538-3881/ab64fa. S2CID 209444271.
- ^ Fragione, Giacomo (2018). "Dynamical origin of S-type planets in close binary stars". Monthly Notices of the Royal Astronomical Society. 483 (3): 3465–3471. arXiv:1812.02754. Bibcode:2019MNRAS.483.3465F. doi:10.1093/mnras/sty3367. S2CID 119457949.