Triangulum Australe (abbeviation: TrA), the Southern Triangle, is a small constellation close to the southern circumpolar region and touched by the southern edge of the Milky Way. Its three leading stars are bright enough to serve as pointers to other constellations nearby, including Apus in the south, Norma in the north, Circinus in the west, and Ara and Pavo in the east. The open cluster NGC 6025 at the boundary with Norma, contains about 30 stars of seventh magnitude and fainter and is a good object for binoculars (distance 2,000 light-years; magnitude 5.1, diameter 12 arcminutes; RA 16h 03.7m, Dec –60° 20'. See below for details of the constellation's brightest stars.

 

Stars brighter than magnitude 4.0
star	visual mag.	abs. mag.	spectral type	distance (lt-yr)	RA (h m s)	Dec (° ' ")
Alpha (Atria)	1.91	-3.62	K2IIIb	415	16 48 40	-69 01 39
Beta	2.83	2.38	F2III	40	15 55 08	-63 25 50
Gamma	2.87	-0.88	A1V	183	15 18 55	-68 40 46
Delta	3.86	-2.54	G5IIa	621	16 15 26	-63 41 08

 

Constellations

Andromeda | Antlia | Apus | Aquarius | Aquila | Ara | Aries | Auriga | Bootes | Caelum | Camelopardalis | Cancer | Canes Venatici | Canis Major | Canis Minor | Capricornus | Carina | Cassiopeia | Centaurus | Cepheus | Cetus | Chamaeleon | Circinus | Columba | Coma Berenices | Corona Austrina | Corona Borealis | Corvus | Crater | Crux | Cygnus | Delphinus | Dorado | Draco | Equuleus | Eridanus | Fornax | Gemini | Grus | Hercules | Horologium | Hydra | Hydrus | Indus | Lacerta | Leo | Leo Minor | Lepus | Libra | Lupus | Lynx | Lyra | Mensa | Microscopium | Monoceros | Musca | Norma | Octans | Ophiuchus | Orion | Pavo | Pegasus | Perseus | Phoenix | Pictor | Pisces | Piscis Austrinus | Puppis | Pyxis | Reticulum | Sagitta | Sagittarius | Scorpius | Sculptor | Scutum | Serpens | Sextans | Taurus | Telescopium | Triangulum | Triangulum Australe | Tucana | Ursa Major | Ursa Minor | Vela | Virgo | Volans | Vulpecula