Skip to content
AsteriaStar
Star · Ophiuchus

HR 6686

Knowledge graphHR 6686HD 163532HIP 87847

Scientific overview

HR 6686 is a star in the constellation Ophiuchus (Ophiuchi), lying about 400.2 light-years from Earth.

Class G. Yellow stars like the Sun. On the main sequence they steadily fuse hydrogen into helium. Such stars have surface temperatures around 5,200–6,000 K and appear yellow to the eye.

Physical properties

Spectral typeG9III
Luminosity classIII
Apparent magnitude5.44
Absolute magnitude0
Luminosity (Sun = 1)87.418
Colour index (B−V)1.162
Distance400.2 ly (122.7 pc)

Values are real catalogue data; fields without a reliable value are omitted, never estimated.

Precision measurements

Astrometry and astrophysics from SIMBAD and Gaia DR3 · Gaia DR3 4177374600431607552

Parallax7.6161 ± 0.0718 masSIMBAD · measured
Distance130.5 pcGaia · estimated
Proper motion (RA)-6.855 mas/yrSIMBAD · measured
Proper motion (Dec)-8.127 mas/yrSIMBAD · measured
Radial velocity-34.2896 ± 7.001e-3 km/sSIMBAD · measured
Spectral typeK2IIICNIb/IISIMBAD · catalogued
Effective temperature4785.1 KGaia · modeled
Radius18.1083 R_sunGaia · modeled
Surface gravity (log g)2.3592 log(cm/s^2)Gaia · modeled
Metallicity [M/H]-0.0698 dexGaia · modeled
Right ascension (ICRS)269.2 degSIMBAD · measured
Declination (ICRS)-4.0818 degSIMBAD · measured
Full field-level provenance
  • Parallax: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · plx_value · 2020yCat.1350....0G · direct catalogue measurement · retrieved 2026-07-11
  • Distance: ESA Gaia astrometric survey · Gaia EDR3 · Bailer-Jones (2021) · external.gaiaedr3_distance · r_med_geo · row 4177374600431607552 · Bayesian estimate · retrieved 2026-07-11
  • Proper motion (RA): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · pmra · 2020yCat.1350....0G · direct catalogue measurement · retrieved 2026-07-11
  • Proper motion (Dec): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · pmdec · 2020yCat.1350....0G · direct catalogue measurement · retrieved 2026-07-11
  • Radial velocity: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · rvz_radvel · 2020AJ....160..120J · direct catalogue measurement · retrieved 2026-07-11
  • Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 1999MSS...C05....0H · catalogue identifier/value · retrieved 2026-07-11
  • Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 4177374600431607552 · model output · retrieved 2026-07-11
  • Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 4177374600431607552 · model output · retrieved 2026-07-11
  • Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 4177374600431607552 · model output · retrieved 2026-07-11
  • Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 4177374600431607552 · model output · retrieved 2026-07-11
  • Right ascension (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · ra · 2020yCat.1350....0G · direct catalogue measurement · retrieved 2026-07-11
  • Declination (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · dec · 2020yCat.1350....0G · direct catalogue measurement · retrieved 2026-07-11

measured = direct catalogue value · estimated = Bayesian inference (Bailer-Jones distance) · modeled = model output (Gaia GSP-Phot). Fields a source did not provide are omitted, never invented.

Location in the sky

Constellation
Ophiuchus
Hemisphere
Both (equatorial)
Best seen
Summer (N. evening sky)
RA / Dec
17.9466h / -4.0818°

Knowledge connections

  • In constellationOphiuchus

Sources

The primary and reference sources this topic draws on.

  • HYG DatabaseHYG Database (Hipparcos + Yale Bright Star + Gliese), by D. Nash / astronexus

    Aggregated, openly-licensed star catalogue combining Hipparcos, the Yale Bright Star Catalogue, and the Gliese Catalogue of Nearby Stars.

  • HipparcosESA Hipparcos space astrometry mission

    High-precision parallax, magnitude, and position for ~118,000 stars.