Beta Monocerotis
Scientific overview
Beta Monocerotis is a main-sequence star in the constellation Monoceros (Monocerotis), lying about 676.7 light-years from Earth.
Class B. Hot, blue-white stars. Massive and luminous, they often light up the regions where they form. Such stars have surface temperatures around 10,000–30,000 K and appear blue-white to the eye.
Physical properties
| Spectral type | B3Ve |
| Luminosity class | V |
| Apparent magnitude | 3.76 |
| Absolute magnitude | -2.82 |
| Luminosity (Sun = 1) | 1,175 |
| Colour index (B−V) | -0.113 |
| Distance | 676.7 ly (207.47 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 3006953165675574272
| Parallax | 4.82 ± 1.12 mas | SIMBAD · measured |
| Distance | 210 pc | Gaia · estimated |
| Proper motion (RA) | -6.86 mas/yr | SIMBAD · measured |
| Proper motion (Dec) | -2.76 mas/yr | SIMBAD · measured |
| Radial velocity | 17.2 ± 2.9 km/s | SIMBAD · measured |
| Spectral type | B4Ve+B2Vn(e)+B3V:nne | SIMBAD · catalogued |
| Right ascension (ICRS) | 97.2045 deg | SIMBAD · measured |
| Declination (ICRS) | -7.0331 deg | SIMBAD · measured |
Full field-level provenance
- Parallax: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · plx_value · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Distance: ESA Gaia astrometric survey · Gaia EDR3 · Bailer-Jones (2021) · external.gaiaedr3_distance · r_med_geo · row 3006953165675574272 · Bayesian estimate · retrieved 2026-07-11
- Proper motion (RA): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · pmra · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Proper motion (Dec): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · pmdec · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Radial velocity: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · rvz_radvel · 2006AstL...32..759G · direct catalogue measurement · retrieved 2026-07-11
- Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 2013yCat....1.2023S · catalogue identifier/value · retrieved 2026-07-11
- Right ascension (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · ra · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Declination (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · dec · 2007A&A...474..653V · 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 main-sequence star fuses hydrogen into helium in its core. It will remain on the main sequence for most of its life before evolving into a giant.
Location in the sky
Knowledge connections
- In constellationMonoceros
Related stars in Monoceros
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.