Zeta Trianguli Australis (ζ TrA) is a spectroscopic binary in the constellation Triangulum Australe. It is approximately 39.5 light years from Earth.
The system is composed of two
main sequence stars, one a yellow-white F-type dwarf and the other a yellow G-type dwarf. The binary's composite spectral class is F9V and its combined apparent magnitude is +4.90. The pair orbit each other once every 13 days, and the orbital eccentricity is 0.014. [3 ]
Somewhat surprisingly for a star located at 70° S, it is a candidate swarm member of the
Ursa Major moving group. However, there is some evidence to the contrary. [4 ] [1 ]
References [ edit ]
^ a b c d Maldonado, J. et al. (October 2010), "A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups", Astronomy and Astrophysics 521: A12, arXiv: 1007.1132, Bibcode: 2010A&A...521A..12M, doi: 10.1051/0004-6361/201014948
^ Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008), "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics", The Astrophysical Journal 687 (2): 1264–1293, arXiv: 0807.1686, Bibcode: 2008ApJ...687.1264M, doi: 10.1086/591785
^ Skuljan, Jovan (2004), "Accurate orbital parameters for the bright southern spectroscopic binary ζ Trianguli Australis – an interesting case of a near-circular orbit", Monthly Notices of the Royal Astronomical Society 352: 975, Bibcode: 2004MNRAS.352..975S, doi: 10.1111/j.1365-2966.2004.07988.x
^ Croswell, Ken (2005). "Descendants of the Dipper". Astronomy 33 (3): 40–45. ISSN 0091-6358.