Gamma Trianguli Australis

Gamma Trianguli Australis (γ TrA, γ Trianguli Australis) is a star in the constellation Triangulum Australe. Along with Alpha and Beta Trianguli Australis it forms a prominent triangular asterism that gives the constellation its name (Latin for southern triangle). It is the third brightest member of this constellation with an apparent visual magnitude of +2.87. based upon parallax measurements, Gamma Trianguli Australis is located at a distance of about 184 light-years (56 parsecs) from Earth.

The spectrum of this star matches a stellar classification of A1 V, which identifies it as an A-type main sequence star that is generating energy through the nuclear fusion of hydrogen at its core. An unusual abundance of the element europium demonstrates it to be a peculiar, or Ap star. Most stars of this type are slow rotators, but Gamma Trianguli Australis displays a very high rate of rotation with a projected rotational velocity of 199 km s–1. It has an estimated age of 260 million years.

This system shows an excess emission of infrared radiation, suggesting that there is a circumstellar disk of dust orbiting this star. The mean temperature of the emission is 50 K, corresponding to a separation from the star of 481 AU.