Beta Arae
Scientific overview
Beta Arae is a red supergiant in the constellation Ara (Arae), lying about 645.9 light-years from Earth.
Class K. Cooler orange stars. Long-lived and abundant; many are stable hosts for planets. Such stars have surface temperatures around 3,700–5,200 K and appear orange to the eye.
Physical properties
| Spectral type | K3Ib-II |
| Luminosity class | Ib |
| Apparent magnitude | 2.84 |
| Absolute magnitude | -3.64 |
| Luminosity (Sun = 1) | 2,498 |
| Colour index (B−V) | 1.479 |
| Distance | 645.9 ly (198.02 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 5922444483103229952 · elevated RUWE
| Parallax | 4.5601 ± 0.2077 mas | SIMBAD · measured |
| Distance | 221.1 pc | Gaia · estimated |
| Proper motion (RA) | -8.039 mas/yr | SIMBAD · measured |
| Proper motion (Dec) | -25.927 mas/yr | SIMBAD · measured |
| Radial velocity | 0.08 ± 0.1 km/s | SIMBAD · measured |
| Spectral type | K0/1Ib | SIMBAD · catalogued |
| Right ascension (ICRS) | 261.3 deg | SIMBAD · measured |
| Declination (ICRS) | -55.5299 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 5922444483103229952 · 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 · 2023A&A...676A.129H · direct catalogue measurement · retrieved 2026-07-11
- Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 1975MSS...C01....0H · 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 supergiant is a colossal, cool, luminous evolved star. The largest known stars are red supergiants, and many end as supernovae.
Location in the sky
Knowledge connections
- In constellationAra
Related stars in Ara
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.