Magnitude 2.87 Apparent magnitude (V) 2.87 | ||
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Similar Alpha Trianguli Australis, Alpha Trianguli, Xi Scorpii, Beta Canis Minoris, Kappa Scorpii | ||
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 astronomical units.