Iota Trianguli Australis

From Wikipedia, the free encyclopedia
Jump to: navigation, search
ι Trianguli Australis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Triangulum Australe
Right ascension 16h 27m 57.3s
Declination −64° 03' 29"
Apparent magnitude (V) +5.28
Distance 132 ± 4 ly
(40 ± 1 pc)
Spectral type F4IV
Other designations
HR 6109, HD 147787, CP-63 3923, HIP 80645, SAO 253555, GC 22100, CCDM 16280-6403

Iota Trianguli Australis (ι TrA, ι Trianguli Australis) is a triple star system in the constellation Triangulum Australe. It is approximately 132 light years from Earth.

It shows itself to be composed of a yellow and a white star when seen though a 7.5 cm telescope.[1]

The primary component, Iota Trianguli Australis A, is a spectroscopic binary with a mean apparent magnitude of +5.28. Both components of the binary star are yellow-white F-type stars and they have an orbital period of 39.8 days. One of the components of the binary is also classified as a Gamma Doradus type variable star, and the binary's brightness varies by 0.12 magnitudes over a period of 1.45 days.[2] The third component of the star system, Iota Trianguli Australis B, is a 10th magnitude star, 20 arcseconds away from the primary.


  1. ^ Hartung, Ernst Johannes (1984). Astronomical Objects for Southern Telescopes, with an Addendum for Northern Observatories: A Handbook for Amateur Observers. CUP Archive. p. 214. ISBN 0521318874. 
  2. ^ De Cat, P.; Wright, D. J.; Pollard, K. R.; Maisonneuve, F.; Kilmartin, P. M. (2009). "Is HD147787 a double-lined binary with two pulsating components? Preliminary results from a spectroscopic multi-site campaign". AIP Conference Proceedings. 1170: 483–85. doi:10.1063/1.3246549.