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One of the three stars that make up the shape of the Triangulum Australe, the Southern Triangle. Gamma Trianguli Australis forms the southwestern corner of the triangle, near the point where Triangulum Australe meets its neighbouring constellations of Ciricnus the Compasses and Apus the Bird of Paradise.

A variable star, even at its brightest this is the faintest of the three stars of the Southern Triangle, but is only marginally less bright than the Beta star, which lies to the north in the sky (though at distance of 184 light years from the Solar System, Gamma Trianguli Australis is considerably more distant than Beta Trianguli Australis).

This a white star on the main sequence (of the type commonly called 'dwarfs') but it shows some peculiarities in comparison with stars of a similar type. Gamma Trianguli Australis rotates on its axis remarkably quickly, and there are indications that it possesses a circumstellar disc. This disc of matter is extremely distant from its star, occupying a region at a distance of nearly 500 AU (for comparison, the planet Neptune orbits the Sun at a distance of about 30 AU).


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