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AsteriaStar
Star · Pisces

Alpherg

Eta Piscium

Knowledge graphEta Psc99 PscHR 437HD 9270

Scientific overview

Alpherg is a star in the constellation Pisces (Piscium), lying about 349.6 light-years from Earth.

Class G. Yellow stars like the Sun. On the main sequence they steadily fuse hydrogen into helium. Such stars have surface temperatures around 5,200–6,000 K and appear yellow to the eye.

Physical properties

Spectral typeG8III
Luminosity classIII
Apparent magnitude3.62
Absolute magnitude-1.53
Luminosity (Sun = 1)357
Colour index (B−V)0.974
Distance349.6 ly (107.18 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 2591891443195067264 · elevated RUWE

Parallax8.7335 ± 0.9207 masSIMBAD · measured
Distance119.7 pcGaia · estimated
Proper motion (RA)28.584 mas/yrSIMBAD · measured
Proper motion (Dec)-3.217 mas/yrSIMBAD · measured
Radial velocity13.78 ± 0.17 km/sSIMBAD · measured
Spectral typeG7IIIaSIMBAD · catalogued
Effective temperature5338.3 KGaia · modeled
Radius33.5303 R_sunGaia · modeled
Surface gravity (log g)1.9778 log(cm/s^2)Gaia · modeled
Metallicity [M/H]-0.2694 dexGaia · modeled
Right ascension (ICRS)22.8709 degSIMBAD · measured
Declination (ICRS)15.3458 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 2591891443195067264 · 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 · 2008AJ....135..209M · direct catalogue measurement · retrieved 2026-07-11
  • Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 1989ApJS...71..245K · catalogue identifier/value · retrieved 2026-07-11
  • Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 2591891443195067264 · model output · retrieved 2026-07-11
  • Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 2591891443195067264 · model output · retrieved 2026-07-11
  • Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 2591891443195067264 · model output · retrieved 2026-07-11
  • Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 2591891443195067264 · 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.

Location in the sky

Constellation
Pisces
Hemisphere
Northern
Best seen
Autumn (N. evening sky)
RA / Dec
1.5247h / 15.3458°

Knowledge connections

  • In constellationPisces

Related stars in Pisces

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.