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AsteriaStar
Subgiant · Ursa Major

23 Ursae Majoris

Knowledge graph23 UMaHR 3757HD 81937HIP 46733

Scientific overview

23 Ursae Majoris is a subgiant in the constellation Ursa Major (Ursae Majoris), lying about 77.67 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 typeF0IV
Luminosity classIV
Apparent magnitude3.65
Absolute magnitude1.77
Luminosity (Sun = 1)17.124
Colour index (B−V)0.36
Distance77.67 ly (23.82 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 1064092789129355136 · elevated RUWE

Parallax42.0904 ± 0.1616 masSIMBAD · measured
Distance23.7287 pcGaia · estimated
Proper motion (RA)107.8 mas/yrSIMBAD · measured
Proper motion (Dec)26.791 mas/yrSIMBAD · measured
Radial velocity-1.38 ± 0.37 km/sSIMBAD · measured
Spectral typeF0VSIMBAD · catalogued
Right ascension (ICRS)142.9 degSIMBAD · measured
Declination (ICRS)63.0619 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 1064092789129355136 · 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 · 2022yCat.1355....0G · 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
  • 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
Ursa Major
Hemisphere
Northern
Best seen
Spring (N. evening sky)
RA / Dec
9.5255h / 63.0619°

Knowledge connections

  • In constellationUrsa Major

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.