Tau Ceti
Scientific overview
Tau Ceti is a yellow dwarf in the constellation Cetus (Ceti), lying about 11.91 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 type | G8V |
| Luminosity class | V |
| Apparent magnitude | 3.49 |
| Absolute magnitude | 5.68 |
| Luminosity (Sun = 1) | 0.466 |
| Colour index (B−V) | 0.727 |
| Distance | 11.91 ly (3.65 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 2452378776434477184 · elevated RUWE
| Parallax | 273.8 ± 0.1701 mas | SIMBAD · measured |
| Distance | 3.6522 pc | Gaia · estimated |
| Proper motion (RA) | -1721.7 mas/yr | SIMBAD · measured |
| Proper motion (Dec) | 855 mas/yr | SIMBAD · measured |
| Radial velocity | -16.597 ± 2.000e-4 km/s | SIMBAD · measured |
| Spectral type | G8V | SIMBAD · catalogued |
| Right ascension (ICRS) | 26.017 deg | SIMBAD · measured |
| Declination (ICRS) | -15.9375 deg | SIMBAD · 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 2452378776434477184 · 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 · 2018A&A...616A...7S · 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
- 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 yellow dwarf is a G-type main-sequence star like the Sun. After about ten billion years it will swell into a red giant and finally leave behind a white dwarf.
Location in the sky
Knowledge connections
- In constellationCetus
- Orbited bytau Cet f
- Orbited bytau Cet g
- Orbited bytau Cet h
Related stars in Cetus
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.