X Trianguli Australis

X Trianguli Australis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Triangulum Australe
Right ascension 15h 14m 19.17535s [1]
Declination −70° 04 46.1052 [1]
Apparent magnitude (V) +5.63
Distance1173 ly
(360 pc)
Spectral typeC5.5(Nb).
Other designations
HR 5644, HD 134453,
CP-69 2267, HIP 74582,
SAO 253062, GC 20436

X Trianguli Australis is a star in the constellation Triangulum Australe. It is a red-hued carbon star with an average apparent magnitude of +5.89. It is approximately 1173 light years (360 parsecs) from Earth,[1] though this could vary by up to 200 light years.[2] It is a semi-regular variable star with two periods of around 385 and 455 days, and is of spectral type C5.5(Nb).[3] It ranges from magnitudes 5.03 to 6.05.[4] Its designation is from the variable star designation developed by German astronomer Friedrich Wilhelm Argelander.

It is a cool star, with estimates of its surface temperature ranging from 2200 to 2700 Kelvin.[2] A giant star, its diameter is 400 times that of the sun, and if placed at the centre of our solar system would stretch out to 30% further than Mars' orbit. Its absolute magnitude is −2.0.[2]

References

  1. 1.0 1.1 1.2 "X Trianguli Australis – Carbon Star". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 18 January 2013.
  2. 2.0 2.1 2.2 Kaler, Jim (19 October 2012). "X Trianguli Australis". Stars. University of Illinois. Retrieved 18 January 2013.
  3. Tabur, V.; Bedding, T. R. (2009). "Long-term Photometry and Periods for 261 Nearby Pulsating M Giants". Monthly Notices of the Royal Astronomical Society 400 (4): 1945–61. doi:10.1111/j.1365-2966.2009.15588.x.
  4. "X TrA". International Variable Star Index. American Association of Variable Star Observers. 11 November 2011. Retrieved 18 January 2013.