HD 170469

HD 170469
Observation data
Epoch J2000      Equinox J2000
Constellation Ophiuchus
Right ascension 18h 29m 10.98124s[1]
Declination +11° 41′ 43.7985″[1]
Apparent magnitude (V) 8.21[2]
Characteristics
Spectral type G5V + K5V[3]
B−V color index 0.677±0.014[2]
Astrometry
Radial velocity (Rv)−59.32±0.10[3] km/s
Proper motion (μ) RA: −48.418±0.070[1] mas/yr
Dec.: −17.470±0.079[1] mas/yr
Parallax (π)16.5886 ± 0.0408 mas[1]
Distance196.6 ± 0.5 ly
(60.3 ± 0.1 pc)
Absolute magnitude (MV)4.23[2]
Orbit[4]
PrimaryHD 170469
CompanionHD 170469 B
Period (P)114000 yr
Semi-major axis (a)43.1″
Details
A
Mass1.10[5] M☉
Radius1.24[5] R☉
Luminosity1.639±0.006[1] L☉
Surface gravity (log g)4.30±0.03[5] cgs
Temperature5,786±28[3] K
Metallicity [Fe/H]0.28±0.02[3] dex
Age4.8+3.0
−0.5[2] or 8.6±0.5[6] Gyr
B
Mass0.42[7] M☉
Other designations
t2 Car, BD+11º3479, Gaia DR2 4484013343859055744, HD 170469, HIP 90593, SAO 103765, 2MASS J18291097+1141437[8]
Database references
SIMBADdata

HD 170469 is a probable binary star[7][4] 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.[2] 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,[3] 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,[3] indicating it is generating energy through core hydrogen fusion. Estimates of the star's age range from five[2] to almost nine[6] billion years. It has 1.10 times the mass of the Sun and 1.24 times the Sun's radius.[5] The star has a higher than solar metallicity.[3] It is radiating 1.64[1] times the Sun's luminosity from its photosphere at an effective temperature of 5,786 K.[3]

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.[3] Initially it was thought to be a red dwarf of spectral class M1,[4] but was later determined to be a K-type main-sequence star with a class of K5V.[3] This star lies at a projected separation of 2708 AU[4] from the primary, and is orbiting with an estimated period of around 114,000 years.[7]

  1. ^ a b c d e f g Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c d e f g h i j Cite error: The named reference Montes2018 was invoked but never defined (see the help page).
  4. ^ a b c d Cite error: The named reference Mugrauer2014 was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference stassun2017 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Bonfanti2015 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference tokovinin2014 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).