Skip to content
AsteriaStar
Red giant · Capricornus

Omega Capricorni

Knowledge graphOmega Cap18 CapHR 7980HD 198542

Scientific overview

Omega Capricorni is a red giant in the constellation Capricornus (Capricorni), lying about 842.8 light-years from Earth.

Class K. Cooler orange stars. Long-lived and abundant; many are stable hosts for planets. Such stars have surface temperatures around 3,700–5,200 K and appear orange to the eye.

Physical properties

Spectral typeK4III
Luminosity classIII
Apparent magnitude4.12
Absolute magnitude-2.94
Luminosity (Sun = 1)1,307
Colour index (B−V)1.633
Distance842.8 ly (258.4 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 6801963487915169920 · elevated RUWE

Parallax5.8975 ± 0.3064 masSIMBAD · measured
Distance171.7 pcGaia · estimated
Proper motion (RA)-9.016 mas/yrSIMBAD · measured
Proper motion (Dec)-2.048 mas/yrSIMBAD · measured
Radial velocity9.1 ± 1.4 km/sSIMBAD · measured
Spectral typeM0IIIBa0.5SIMBAD · catalogued
Effective temperature4473.8 KGaia · modeled
Radius67.875 R_sunGaia · modeled
Surface gravity (log g)0.8421 log(cm/s^2)Gaia · modeled
Metallicity [M/H]-1.8096 dexGaia · modeled
Right ascension (ICRS)313 degSIMBAD · measured
Declination (ICRS)-26.9191 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 6801963487915169920 · 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 · 1989ApJS...71..245K · catalogue identifier/value · retrieved 2026-07-11
  • Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 6801963487915169920 · model output · retrieved 2026-07-11
  • Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 6801963487915169920 · model output · retrieved 2026-07-11
  • Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 6801963487915169920 · model output · retrieved 2026-07-11
  • Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 6801963487915169920 · 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 red giant is an evolved star that has exhausted core hydrogen and expanded enormously, cooling at its surface as it fuses heavier elements in shells.

Location in the sky

Constellation
Capricornus
Hemisphere
Southern
Best seen
Summer (N. evening sky)
RA / Dec
20.8637h / -26.9191°

Knowledge connections

  • In constellationCapricornus

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.