IAU Constellation (Cen) · Genitive: Centauri · Southern Sky

Centaurus Constellation Guide & Objects

Centaurus IAU constellation guide: giant southern constellation (1060 sq deg) hosting Omega Centauri, Alpha Centauri, Proxima Centauri, and Proxima b.

Solid-Angle Area1060 sq deg (Rank #9 of 88)
Best Evening MonthMay
Visibility Latitudes+25° to −90°
Brightest StarAlpha Centauri (Rigil Kentaurus) (−0.27)

Sky Navigation & Astrophysical Context

Centaurus is the ninth-largest constellation in the sky, sweeping across 1,060 square degrees of the southern Milky Way and wrapping around three sides of Crux (the Southern Cross). Its two zero- and first-magnitude Southern Pointer stars—Alpha Centauri (Rigil Kentaurus, V = −0.27) and Beta Centauri (Hadar, V = +0.61)—guide observers directly to Crux.

Part of the Alpha Centauri triple system at 1.302 parsecs (4.246 light-years) is the M5.5 Ve red dwarf Proxima Centauri, the closest individual star to our Solar System and host to the temperate terrestrial exoplanet Proxima Centauri b.

Fifteen degrees north of the Southern Cross, at declination −47° 29′, shines Omega Centauri (NGC 5139), the most massive and luminous globular cluster in the Milky Way (~4 × 10⁶ solar masses, V = +3.9), easily visible to the unaided eye as a fuzzy 4th-magnitude star.

Bordering IAU Constellations: Antlia, Carina, Circinus, Crux, Hydra, Lupus, Musca, Vela.

Equatorial Center Position & Transit Altitude

Centaurus is centered near Right Ascension 13h 00m 00s, Declination −47° 00′ 00″ (The Centaur).

J2000 Equatorial Sky Position (Centaurus) +90° 0° −90° 24h 12h RA 0h Peak Meridian Altitude 3° 40°N Lat 73° 30°S Lat RA: 13h 00m 00s Dec: −47° 00′ 00″ Epoch: J2000.0 · 1060 sq deg (Rank #9) First-party vector diagram derived from IAU / CDS SIMBAD / Gaia DR3 astrometry.

Practical Star-Hopping & Observing Tips

  • From latitudes south of +25°N, use the Southern Pointers (Alpha and Beta Centauri) to orient around Crux and the southern Milky Way.
  • Sweep 5° north of Zeta Centauri (or 15° north of Crux) with binoculars to see the sprawling, slightly flattened globe of Omega Centauri.
  • Locate magnitude +11.13 Proxima Centauri 2.18° southwest of Alpha Centauri AB using a detailed finder chart and a 150 mm+ telescope.

Notable Celestial Objects in & Near Centaurus

Cataloged Stars and Deep-Sky Objects Associated with Centaurus
ObjectFamilyClassificationRA (J2000)Dec (J2000)Min. Instrument
Omega Centauri (NGC 5139 Cluster)globular-clustersGlobular cluster / stripped dwarf galaxy nucleus13h 26m 47.24s-47° 28′ 46.1″Naked eye (south of 35°N)
Proxima Centauri (Nearest Star to Sun)starsRed dwarf flare star (nearest extrasolar star to the Sun)14h 29m 42.95s-62° 40′ 46.1″80–100 mm telescope with detailed finder chart (Southern Hemisphere / low northern latitudes)
Proxima Centauri b (Nearest Exoplanet)exoplanetsNearest known exoplanet (radial-velocity habitable-zone terrestrial candidate)14h 29m 42.95s-62° 40′ 46.1″80–100 mm telescope to view the 11.13-mag host star Proxima Centauri
47 Tucanae (NGC 104 Globular Cluster)globular-clustersGlobular cluster00h 24m 05.30s-72° 04′ 52.6″Naked eye (Southern Hemisphere)

Scientific Sources Cited