4 Orionis
Scientific overview
4 Orionis is a red dwarf in the constellation Orion (Orionis), lying about 651 light-years from Earth.
Class M. Cool red stars. The most common type in the galaxy, ranging from red dwarfs to red giants. Such stars have surface temperatures around 2,400–3,700 K and appear red to the eye.
Physical properties
| Spectral type | M3Sv |
| Apparent magnitude | 4.71 |
| Absolute magnitude | -1.79 |
| Luminosity (Sun = 1) | 453 |
| Colour index (B−V) | 1.773 |
| Distance | 651 ly (199.6 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 3296627028792695168 · elevated RUWE
| Parallax | 5.8125 ± 0.2035 mas | SIMBAD · measured |
| Distance | 170.9 pc | Gaia · estimated |
| Proper motion (RA) | 1.422 mas/yr | SIMBAD · measured |
| Proper motion (Dec) | -54.863 mas/yr | SIMBAD · measured |
| Radial velocity | -8.4 ± 0.23 km/s | SIMBAD · measured |
| Spectral type | M3SIII | SIMBAD · catalogued |
| Right ascension (ICRS) | 73.1332 deg | SIMBAD · measured |
| Declination (ICRS) | 14.2506 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 3296627028792695168 · 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 · 2005A&A...430..165F · direct catalogue measurement · retrieved 2026-07-11
- Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 1990A&AS...85.1069S · 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 red dwarf is a small, cool, low-mass main-sequence star. Red dwarfs burn their fuel so slowly that they can shine for tens of billions of years — far longer than the present age of the universe.
Location in the sky
Knowledge connections
- In constellationOrion
Related stars in Orion
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.