Zeta Gruis

Zeta Gruis, Latinised from ζ Gruis, is a solitary star in the southern constellation of Grus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.12. Based upon an annual parallax shift of 24.5 mas as seen from the Earth, the system is located about 133 light-years from the Sun.

This is an evolved K-type giant star with a stellar classification of K1 III Fe−1.2 CN−0.5, where the suffix notation indicates underabundances of iron and cyanogen in the spectrum. Having exhausted the supply of hydrogen at its core, the star has expanded and cooled; at present it has 10 times the girth of the Sun. The star is radiating 46 times the luminosity of the Sun from its swollen photosphere at an effective temperature of $−1.1$.