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AsteriaStar
Subgiant · Libra

Epsilon Librae

Knowledge graphEpsilon Lib31 LibHR 5723HD 137052

Scientific overview

Epsilon Librae is a subgiant in the constellation Libra (Librae), lying about 101.86 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 typeF5IV
Luminosity classIV
Apparent magnitude4.92
Absolute magnitude2.45
Luminosity (Sun = 1)9.145
Colour index (B−V)0.453
Distance101.86 ly (31.23 pc)

Values are real catalogue data; fields without a reliable value are omitted, never estimated.

Precision measurements

Astrometry and astrophysics from SIMBAD

Parallax34.6222 ± 0.6092 masSIMBAD · measured
Proper motion (RA)-66.816 mas/yrSIMBAD · measured
Proper motion (Dec)-152.3 mas/yrSIMBAD · measured
Radial velocity-11.68 ± 3.24 km/sSIMBAD · measured
Spectral typeF4VSIMBAD · catalogued
Right ascension (ICRS)231 degSIMBAD · measured
Declination (ICRS)-10.3223 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
  • 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 · 2022yCat.1355....0G · direct catalogue measurement · retrieved 2026-07-11
  • Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 2009ApJS..180..117A · 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
Libra
Hemisphere
Both (equatorial)
Best seen
Summer (N. evening sky)
RA / Dec
15.4033h / -10.3223°

Knowledge connections

  • In constellationLibra

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.