- Triangle (Wikipedia)
A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry. A triangle with vertices A, B, and C is denoted △ABC.
- Southern celestial hemisphere (Wikipedia)
The southern celestial hemisphere, also called the Southern Sky, is the southern half of the celestial sphere; that is, it lies south of the celestial equator. This arbitrary sphere, on which seemingly fixed stars form constellations, appears to rotate westward around a polar axis due to Earth’s rotation.
- Triangulum Australe is a small constellation in the far Southern Celestial Hemisphere. Its name is Latin for “the southern triangle”, which distinguishes it from Triangulum in the northern sky and is derived from the acute, almost equilateral pattern of its three brightest stars. It was first depicted on a celestial globe as Triangulus Antarcticus by Petrus Plancius in 1589, and later with more accuracy and its current name by Johann Bayer in his 1603 Uranometria. The French explorer and astronomer Nicolas Louis de Lacaille charted and gave the brighter stars their Bayer designations in 1756.
- NGC 6025 (Wikipedia)
NGC 6025 (also known as Caldwell 95) is an open cluster located 2,700 light years away in the Triangulum Australe constellation. It was discovered by Abbe Lacaille in 1751 during his expedition to the Cape of Good Hope.
- Triangulum (Wikipedia)
Triangulum is a small constellation in the northern sky. Its name is Latin for “triangle”, derived from its three brightest stars, which form a long and narrow triangle. Known to the ancient Babylonians and Greeks, Triangulum was one of the 48 constellations listed by the 2nd century astronomer Ptolemy. The celestial cartographers Johann Bayer and John Flamsteed catalogued the constellation’s stars, giving six of them Bayer designations.
- Beta Trianguli Australis (Wikipedia)
Beta Trianguli Australis, Latinized from β Trianguli Australis, is a double star in the southern constellation of Triangulum Australe. It is approximately 40.37 light-years (12.38 parsecs) from Earth and has an apparent visual magnitude of +2.85. This star has a relatively high rate of proper motion across the celestial sphere. It is a F-type main-sequence star with a stellar classification of F1 V. Beta TrA has a 14th magnitude optical companion at an angular separation of 155 arcseconds.
- Gamma Trianguli Australis (Wikipedia)
Gamma Trianguli Australis, Latinized from γ Trianguli Australis, is a single, white-hued star in the southern constellation of 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 190 light-years (58 parsecs) from Earth.
