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AsteriaStar
Blue giant · Capricornus

30 Capricorni

Knowledge graph30 CapHR 8137HD 202671HIP 105143

Scientific overview

30 Capricorni is a blue giant in the constellation Capricornus (Capricorni), lying about 533.8 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 typeB5II/III
Luminosity classIII
Apparent magnitude5.4
Absolute magnitude-0.67
Luminosity (Sun = 1)161
Colour index (B−V)-0.118
Distance533.8 ly (163.67 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 6834597233540521216

Parallax4.277 ± 0.1134 masSIMBAD · measured
Distance230.9 pcGaia · estimated
Proper motion (RA)16.026 mas/yrSIMBAD · measured
Proper motion (Dec)-0.967 mas/yrSIMBAD · measured
Radial velocity-11.1 ± 0.9 km/sSIMBAD · measured
Spectral typeB5II/IIISIMBAD · catalogued
Effective temperature12713 KGaia · modeled
Radius5.4514 R_sunGaia · modeled
Surface gravity (log g)3.5018 log(cm/s^2)Gaia · modeled
Metallicity [M/H]-1.2998 dexGaia · modeled
Right ascension (ICRS)319.5 degSIMBAD · measured
Declination (ICRS)-17.9851 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 6834597233540521216 · 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 · 1988MSS...C04....0H · catalogue identifier/value · retrieved 2026-07-11
  • Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 6834597233540521216 · model output · retrieved 2026-07-11
  • Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 6834597233540521216 · model output · retrieved 2026-07-11
  • Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 6834597233540521216 · model output · retrieved 2026-07-11
  • Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 6834597233540521216 · 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 blue giant is a hot, massive, highly luminous star that has evolved off the main sequence. Such stars are short-lived on cosmic timescales.

Location in the sky

Constellation
Capricornus
Hemisphere
Southern
Best seen
Summer (N. evening sky)
RA / Dec
21.2992h / -17.9851°

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.