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AsteriaStar
Main-sequence star · Cygnus

68 Cygni

Knowledge graph68 CygHR 8154HD 203064HIP 105186

Scientific overview

68 Cygni is a main-sequence star in the constellation Cygnus (Cygni).

Class O. Extremely hot, luminous blue stars. They are massive, short-lived, and rare, pouring out ultraviolet light. Such stars have surface temperatures around ≥ 30,000 K and appear blue to the eye.

Physical properties

Spectral typeO8
Apparent magnitude5.04
Colour index (B−V)-0.061

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 1971467916750747264 · elevated RUWE

Parallax1.4498 ± 0.1152 masSIMBAD · measured
Distance696.3 pcGaia · estimated
Proper motion (RA)4.632 mas/yrSIMBAD · measured
Proper motion (Dec)-8.487 mas/yrSIMBAD · measured
Radial velocity1 ± 5 km/sSIMBAD · measured
Spectral typeO7.5IIIn((f))SIMBAD · catalogued
Effective temperature21118.3 KGaia · modeled
Radius11.9802 R_sunGaia · modeled
Surface gravity (log g)3.3568 log(cm/s^2)Gaia · modeled
Metallicity [M/H]0.0199 dexGaia · modeled
Right ascension (ICRS)319.6 degSIMBAD · measured
Declination (ICRS)43.9459 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 1971467916750747264 · 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 · 1953GCRV..C......0W · direct catalogue measurement · retrieved 2026-07-11
  • Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 2011ApJS..193...24S · catalogue identifier/value · retrieved 2026-07-11
  • Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 1971467916750747264 · model output · retrieved 2026-07-11
  • Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 1971467916750747264 · model output · retrieved 2026-07-11
  • Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 1971467916750747264 · model output · retrieved 2026-07-11
  • Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 1971467916750747264 · 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.

Evolution

A main-sequence star fuses hydrogen into helium in its core. It will remain on the main sequence for most of its life before evolving into a giant.

Location in the sky

Constellation
Cygnus
Hemisphere
Northern
Best seen
Summer (N. evening sky)
RA / Dec
21.3076h / 43.9459°

Knowledge connections

  • In constellationCygnus

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.