IAU Constellation (Ant) · Genitive: Antliae · Southern Sky

Antlia (The Air Pump) Constellation Guide

Antlia IAU constellation (239 sq deg, rank 62): culmination in April, led by +4.25 Alpha Antliae and the nearby Antlia Galaxy Cluster (Abell S0636).

Solid-Angle Area239 sq deg (Rank #62 of 88)
Best Evening MonthApril
Visibility Latitudes+45° to −90°
Brightest StarAlpha Antliae (+4.25)

Sky Navigation & Astrophysical Context

Antlia occupies 239 square degrees of the southern spring sky between the sprawling body of Hydra to the north and the rich Milky Way star fields of Vela and Centaurus to the south. Introduced in the 1750s by the French astronomer Nicolas-Louis de Lacaille as 'la Machine Pneumatique' to honor the invention of the vacuum air pump by Denis Papin and Robert Boyle, Antlia lacks any stars brighter than fourth magnitude; its luminary is the K4 III orange giant Alpha Antliae at visual magnitude +4.25.

Because Antlia sits approximately 15° to 25° north of the galactic plane, interstellar dust absorption begins to thin across its northern boundary, opening an extragalactic window toward the Hydra-Centaurus Supercluster. Within southern Antlia lies the Antlia Cluster (Abell S0636), the third-nearest galaxy cluster to the Local Group after the Virgo and Fornax clusters, anchored by the massive elliptical galaxies NGC 3258 and NGC 3268 at a distance of roughly 40 megaparsecs.

At the local galactic edge, Antlia also hosts the Antlia Dwarf (PGC 29194), a low-surface-brightness dwarf spheroidal/irregular transition galaxy orbiting at the outer fringe of the Local Group (~1.3 megaparsecs), as well as the dusty spiral NGC 2997 and the carbon star U Antliae surrounded by a detached circumstellar shell resolved in submillimeter interferometry.

Bordering IAU Constellations: Hydra, Pyxis, Vela, Centaurus.

Equatorial Center Position & Transit Altitude

Antlia is centered near Right Ascension 10h 16m 12s, Declination −32° 28′ 48″ (The Air Pump).

J2000 Equatorial Sky Position (Antlia) +90° 0° −90° 24h 12h RA 0h Peak Meridian Altitude 18° 40°N Lat 88° 30°S Lat RA: 10h 16m 12s Dec: −32° 28′ 48″ Epoch: J2000.0 · 239 sq deg (Rank #62) First-party vector diagram derived from IAU / CDS SIMBAD / Gaia DR3 astrometry.

Practical Star-Hopping & Observing Tips

  • Sweep 10° north of the Vela sail stars toward Alphard in Hydra under dark skies to trace the faint triangle of Alpha, Epsilon, and Iota Antliae.
  • Use a 200 mm+ aperture telescope at 100× near Alpha Antliae to spot the 45°-inclined grand-design spiral galaxy NGC 2997 (V = +9.4) and the elliptical pair NGC 3258/3268.
  • In 100 mm telescopes, split the balanced double star Zeta¹ Antliae (magnitudes +6.2 and +7.0 separated by 8.0 arcseconds).

Notable Celestial Objects in & Near Antlia

Cataloged Stars and Deep-Sky Objects Associated with Antlia
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)
Carina Nebula (NGC 3372 Star-Forming Cloud)nebulaeGiant H II region and massive OB star-forming complex10h 45m 07.00s-59° 52′ 00.0″Naked eye and binoculars (south of 30°N)

Scientific Sources Cited