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AsteriaStar
Main-sequence star · Aquila

Sigma Aquilae

Knowledge graphSigma Aql44 AqlHR 7474HD 185507

Scientific overview

Sigma Aquilae is a main-sequence star in the constellation Aquila (Aquilae), lying about 780.3 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 typeB3V + B3V
Luminosity classV
Apparent magnitude5.18
Absolute magnitude-1.71
Luminosity (Sun = 1)422
Colour index (B−V)-0.001
Distance780.3 ly (239.23 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 4291462091610511744

Parallax4.1557 ± 0.0775 masSIMBAD · measured
Distance238.6 pcGaia · estimated
Proper motion (RA)4.528 mas/yrSIMBAD · measured
Proper motion (Dec)-4.507 mas/yrSIMBAD · measured
Radial velocity-4.8 ± 0.9 km/sSIMBAD · measured
Spectral typeB3VSIMBAD · catalogued
Effective temperature16194.5 KGaia · modeled
Radius5.9053 R_sunGaia · modeled
Surface gravity (log g)3.6795 log(cm/s^2)Gaia · modeled
Metallicity [M/H]0.1512 dexGaia · modeled
Right ascension (ICRS)294.8 degSIMBAD · measured
Declination (ICRS)5.3978 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 4291462091610511744 · 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 · 1976A&AS...26..241C · catalogue identifier/value · retrieved 2026-07-11
  • Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 4291462091610511744 · model output · retrieved 2026-07-11
  • Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 4291462091610511744 · model output · retrieved 2026-07-11
  • Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 4291462091610511744 · model output · retrieved 2026-07-11
  • Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 4291462091610511744 · 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
Aquila
Hemisphere
Both (equatorial)
Best seen
Summer (N. evening sky)
RA / Dec
19.6532h / 5.3978°

Knowledge connections

  • In constellationAquila

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.