HD 158614

HD 158614
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Ophiuchus
Right ascension 17h 30m 23.79699s[1]
Declination −01° 03′ 46.4882″[1]
Apparent magnitude (V) +5.31[2] (6.02 + 5.93)[3]
Characteristics
Evolutionary stage Subgiant[4]
Spectral type G9IV-V + G9IV-V[3]
B−V color index +0.715±0.013[5]
Astrometry
Radial velocity (Rv)−76.98±0.05[5] km/s
Proper motion (μ) RA: −127.77[1] mas/yr
Dec.: −168.61[1] mas/yr
Parallax (π)61.19 ± 0.68 mas[1]
Distance53.3 ± 0.6 ly
(16.3 ± 0.2 pc)
Absolute magnitude (MV)4.24[5]
Orbit[3]
Period (P)46.34±0.021 yr
Semi-major axis (a)977.±3.3 mas
Eccentricity (e)0.168±0.0025
Inclination (i)99.1±0.11°
Longitude of the node (Ω)332.3±0.13°
Periastron epoch (T)1870.0±0.16 Byr
Argument of periastron (ω)
(secondary)		148.±1.3°
Details
A
Mass0.963±0.005[6] M☉
Radius1.7[2] R☉
Luminosity2.5[2] L☉
Surface gravity (log g)4.00[2] cgs
Temperature5,500±150[2] K
Age12.3[7] Gyr
B
Mass0.951±0.005[6] M☉
Other designations
STF 2173, BD−00°3300, GJ 678, HIP 85667, HR 6516, SAO 141702, WDS J17304-0104[8]
Database references
SIMBADdata

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.[2] 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[5] and is predicted to come to within 11.0 light-years in around 196,000 years.[9] The system has been included as a candidate member of the Zeta Herculis moving group.[10] However, chemical abundances appear to rule that out.[11]

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,[12] yielding orbital elements showing a period of 46.3 years and an eccentricity of 0.17.[3] The two components have similar spectra that match a stellar classification of G9IV-V.[3] They show almost no luminosity variation; one of the pair appears to vary by 0.002 in magnitude.[4] Both components have a slightly lower mass than the Sun: 96% and 95%, respectively.[6] The system is estimated to be 12.3 billion years old.[7]

This binary was included in a search for brown dwarfs that turned up no large companions.[citation needed]

  1. ^ a b c d e Cite error: The named reference aaa474_2_653 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference aass85_3_1015 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference Pourbaix2000 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Lockwood1998 was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference Andrade2019 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Casagrande2011 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Bailer-Jones2015 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference deMello_daSilva_1991 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Ferreira2010 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Batten1991 was invoked but never defined (see the help page).