HD 158614
Binary star in the constellation Ophiuchus
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HD 158614 is a visual binary star system in the equatorial constellation of Ophiuchus. The system is visible to the naked eye with a combined apparent visual magnitude of +5.31.[3] It is located at a distance of 53.3 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −77 km/s[1] and is predicted to come to within 11.0 light-years in around 196,000 years.[8] The system has been included as a candidate member of the Zeta Herculis moving group.[9] However, chemical abundances appear to rule that out.[10]
| Observation data Epoch J2000.0 Equinox ICRS | |
|---|---|
| Constellation | Ophiuchus[1] |
| Right ascension | 17h 30m 23.79699s[2] |
| Declination | −01° 03′ 46.4882″[2] |
| Apparent magnitude (V) | +5.31[3] (6.02 + 5.93)[4] |
| Characteristics | |
| Evolutionary stage | Subgiant[5] |
| Spectral type | G9IV-V + G9IV-V[4] |
| B−V color index | +0.715±0.013[1] |
| Astrometry | |
| Radial velocity (Rv) | −77.197±0.064[6] km/s |
| Proper motion (μ) | RA: −127.77[2] mas/yr Dec.: −168.61[2] mas/yr |
| Parallax (π) | 61.19±0.68 mas[2] |
| Distance | 53.3 ± 0.6 ly (16.3 ± 0.2 pc) |
| Absolute magnitude (MV) | 4.24[1] |
| Orbit[6] | |
| Period (P) | 46.585±0.023 yr |
| Semi-major axis (a) | 969.71±0.60 mas |
| Eccentricity (e) | 0.17636±0.00074 |
| Inclination (i) | 99.177±0.037° |
| Longitude of the node (Ω) | 151.769±0.033° |
| Periastron epoch (T) | 2008.601±0.037 |
| Argument of periastron (ω) (secondary) | 324.57±0.32° |
| Semi-amplitude (K1) (primary) | 5.00±0.11 km/s |
| Semi-amplitude (K2) (secondary) | 5.40±0.11 km/s |
| Details | |
| A | |
| Mass | 1.018±0.048[6] M☉ |
| B | |
| Mass | 0.943±0.046[6] M☉ |
| Other designations | |
| STF 2173, BD−00°3300, GJ 678, HIP 85667, HR 6516, SAO 141702, WDS J17304-0104[7] | |
| Database references | |
| SIMBAD | data |
The pair were found to be a double star by F. G. W. Struve in 1827 and given the catalogue identifier Σ 2173 (now STF 2173). Since then it has completed multiple orbits,[11] yielding orbital elements showing a period of 46.585 years and an eccentricity of 0.17636.[6] The two components have similar spectra that match a stellar classification of G9IV-V.[4] They show almost no luminosity variation; one of the pair appears to vary by 0.002 in magnitude.[5] Both components have masses similar to that of the Sun: 102% and 94%, respectively.[6]