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AsteriaStar
Subgiant · Cepheus

6 Cephei

Knowledge graph6 CepHR 8171HD 203467HIP 105268

Scientific overview

6 Cephei is a subgiant in the constellation Cepheus (Cephei), lying about 1,988.8 light-years from Earth.

Class B. Hot, blue-white stars. Massive and luminous, they often light up the regions where they form. Such stars have surface temperatures around 10,000–30,000 K and appear blue-white to the eye.

Physical properties

Spectral typeB3IVe
Luminosity classIV
Apparent magnitude5.19
Absolute magnitude-3.74
Luminosity (Sun = 1)2,719
Colour index (B−V)-0.045
Distance1,988.8 ly (609.76 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 2220601656582906880

Parallax2.4791 ± 0.0703 masSIMBAD · measured
Distance399.1 pcGaia · estimated
Proper motion (RA)5.472 mas/yrSIMBAD · measured
Proper motion (Dec)5.921 mas/yrSIMBAD · measured
Radial velocity-16.5 ± 1.4 km/sSIMBAD · measured
Spectral typeB3IVeSIMBAD · catalogued
Right ascension (ICRS)319.8 degSIMBAD · measured
Declination (ICRS)64.8719 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 2220601656582906880 · 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 · 2006AstL...32..759G · direct catalogue measurement · retrieved 2026-07-11
  • Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · catalogue identifier/value · 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 subgiant has begun to evolve off the main sequence, brightening and expanding as core hydrogen fusion ends.

Location in the sky

Constellation
Cepheus
Hemisphere
Northern
Best seen
Summer (N. evening sky)
RA / Dec
21.3228h / 64.8719°

Knowledge connections

  • In constellationCepheus

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.