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AsteriaStar
Main-sequence star · Eridanus

51 Eridani

Knowledge graph51 EriHR 1474HD 29391HIP 21547

Scientific overview

51 Eridani is a main-sequence star in the constellation Eridanus (Eridani), lying about 95.98 light-years from Earth.

Class F. Yellow-white stars, somewhat hotter and more massive than the Sun. Such stars have surface temperatures around 6,000–7,500 K and appear yellow-white to the eye.

Physical properties

Spectral typeF0V
Luminosity classV
Apparent magnitude5.22
Absolute magnitude2.88
Luminosity (Sun = 1)6.16
Colour index (B−V)0.283
Distance95.98 ly (29.43 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 3205095125321700480

Parallax33.439 ± 0.0777 masSIMBAD · measured
Distance29.8755 pcGaia · estimated
Proper motion (RA)44.049 mas/yrSIMBAD · measured
Proper motion (Dec)-64.028 mas/yrSIMBAD · measured
Radial velocity12.6 ± 0.3 km/sSIMBAD · measured
Spectral typeF0IVSIMBAD · catalogued
Effective temperature7250.3 KGaia · modeled
Radius1.5529 R_sunGaia · modeled
Surface gravity (log g)4.1396 log(cm/s^2)Gaia · modeled
Metallicity [M/H]-0.7163 dexGaia · modeled
Right ascension (ICRS)69.4006 degSIMBAD · measured
Declination (ICRS)-2.4735 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 3205095125321700480 · 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 · 1995ApJS...99..135A · catalogue identifier/value · retrieved 2026-07-11
  • Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 3205095125321700480 · model output · retrieved 2026-07-11
  • Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 3205095125321700480 · model output · retrieved 2026-07-11
  • Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 3205095125321700480 · model output · retrieved 2026-07-11
  • Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 3205095125321700480 · 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
Eridanus
Hemisphere
Both (equatorial)
Best seen
Winter (N. evening sky)
RA / Dec
4.6267h / -2.4735°

Knowledge connections

  • In constellationEridanus
  • Orbited by51 Eri b

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.