| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ophiuchus |
| Right ascension | 18 29 10.98124 |
| Declination | +11° 41′ 43.7985″ |
| Apparent magnitude (V) | 8.21 |
| Characteristics | |
| Spectral type | G5V + K5V |
| B−V color index | 0.677±0.014 |
| Astrometry | |
| Radial velocity (Rv) | −59.32±0.10 km/s |
| Proper motion (μ) | RA: −48.418±0.070 mas/yr Dec.: −17.470±0.079 mas/yr |
| Parallax (π) | 16.5886 ± 0.0408 mas |
| Distance | 196.6 ± 0.5 ly (60.3 ± 0.1 pc) |
| Absolute magnitude (MV) | 4.23 |
| Orbit | |
| Primary | HD 170469 |
| Companion | HD 170469 B |
| Period (P) | 114000 yr |
| Semi-major axis (a) | 43.1″ |
| Details | |
| A | |
| Mass | 1.10 M☉ |
| Radius | 1.24 R☉ |
| Luminosity | 1.639±0.006 L☉ |
| Surface gravity (log g) | 4.30±0.03 cgs |
| Temperature | 5,786±28 K |
| Metallicity | 0.28±0.02 dex |
| Age | 4.8+3.0 −0.5 or 8.6±0.5 Gyr |
| B | |
| Mass | 0.42 M☉ |
| Other designations | |
| t Car, BD+11º3479, Gaia DR2 4484013343859055744, HD 170469, HIP 90593, SAO 103765, 2MASS J18291097+1141437 | |
| Database references | |
| SIMBAD | data |
HD 170469 is a probable binary star system in the equatorial constellation of Ophiuchus. It is too faint to be viewed with the naked eye, having an apparent visual magnitude of 8.21. The system is located at a distance of 197 light years away from the Sun based on parallax. It is drifting closer with a radial velocity of −59 km/s, and is expected to come to within 49.8 light-years in about 959,000 years.
The primary, component A, is a G-type main-sequence star with a stellar classification of G5V, indicating it is generating energy through core hydrogen fusion. Estimates of the star's age range from five to almost nine billion years. It has 1.10 times the mass of the Sun and 1.24 times the Sun's radius. The star has a higher than solar metallicity. It is radiating 1.64 times the Sun's luminosity from its photosphere at an effective temperature of 5,786 K.
The secondary companion, component B, is located at an angular separation of 43.21″±0.10″ along a position angle of 112.55°±0.07° from the primary, as of 2018. Initially it was thought to be a red dwarf of spectral class M1, but was later determined to be a K-type main-sequence star with a class of K5V. This star lies at a projected separation of 2708 AU from the primary, and is orbiting with an estimated period of around 114,000 years.
Planetary system
In 2007, a planet was discovered by the N2K Consortium, led by principal investigators Debra Fischer and Gregory P. Laughlin. It was spotted using the radial velocity method, and was independently confirmed in 2014.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >0.67 MJ | 2.24 | 1,143 | 0.11 | — | — |
See also
References
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ 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.
- ^ Montes, D.; et al. (September 2018). "Calibrating the metallicity of M dwarfs in wide physical binaries with F-, G-, and K-primaries - I: High-resolution spectroscopy with HERMES: stellar parameters, abundances, and kinematics". Monthly Notices of the Royal Astronomical Society. 479 (1): 1332–1382. arXiv:1805.05394. Bibcode:2018MNRAS.479.1332M. doi:10.1093/mnras/sty1295. S2CID 119260219.
- ^ Mugrauer, M.; et al. (March 2014). "New wide stellar companions of exoplanet host stars". Monthly Notices of the Royal Astronomical Society. 439 (1): 1063–1070. Bibcode:2014MNRAS.439.1063M. doi:10.1093/mnras/stu044.
- ^ Stassun, Keivan G.; et al. (2017). "Accurate Empirical Radii and Masses of Planets and Their Host Stars with Gaia Parallaxes". The Astronomical Journal. 153 (3): 136. arXiv:1609.04389. Bibcode:2017AJ....153..136S. doi:10.3847/1538-3881/aa5df3. S2CID 119219062.
- ^ Bonfanti, A.; et al. (March 2015). "Revising the ages of planet-hosting stars". Astronomy & Astrophysics. 575: 17. arXiv:1411.4302. Bibcode:2015A&A...575A..18B. doi:10.1051/0004-6361/201424951. S2CID 54555839. A18.
- ^ Tokovinin, Andrei (2014). "From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs". The Astronomical Journal. 147 (4): 87. arXiv:1401.6827. Bibcode:2014AJ....147...87T. doi:10.1088/0004-6256/147/4/87. S2CID 56066740.
- "HD 170469". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-13.
- ^ Fischer, Debra A.; et al. (2007). "Five Intermediate-Period Planets from the N2K Sample". The Astrophysical Journal. 669 (2): 1336–1344. arXiv:0704.1191. Bibcode:2007ApJ...669.1336F. doi:10.1086/521869. S2CID 7774321.
