Artikel: Gamma Trianguli Australis GudangMovies21 Rebahinxxi

    • Source: Gamma Trianguli Australis

      • 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.


      Characteristics


      The spectrum of this star matches a stellar classification of A1 III, which identifies it as a giant star. It could be also a subgiant. An unusual abundance of the element europium demonstrates it to be a peculiar, or Ap star. However, its classification as a chemically peculiar star is doubtful. 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.
      At a mass of 3.04 solar masses, Gamma Trianguli Australis was a late B-type star (B8V/B9V) in the main sequence. Being 350 million years old, it has recently begun its expansion towards a red giant. Its radius is either 6.5 R☉ (estimated using stellar isochrones) or 7 R☉ (measured). The star is emitting a luminosity equivalent to 250 solar luminosities. Its surface has an effective temperature of 8,225 K. This is around 2,450 K hotter than the Sun and gives it a white hue, typical of A-type stars.
      This star 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.


      Reported companion star


      The Gaia Data Release 3 (Gaia DR3) reported Gamma Trianguli Australis as an astrometric binary with a period of 488 days (1.34 years). The companion star would be a red dwarf with a mass of 0.15 M☉ and a semimajor axis of 1.8 AU. However, a further study using the Very Large Telescope did not found any evidence of a companion.


      Modern legacy


      γ TrA appears on the flag of Brazil, symbolising the state of Paraná.


      References

    Kata Kunci Pencarian:

    gamma trianguli australis