Английская Википедия:Gamma3 Octantis

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Gamma³ Octantis, Latinized from γ³ Octantis, is a solitary star located in the southern circumpolar constellation Octans. It is faintly visible to the naked eye as an orange-hued star with an apparent magnitude of 5.28. The object is located relatively close at a distance of 264 light years but is receding with a heliocentric radial velocity of Шаблон:Val. At its current distance, Gamma³ Octantis' brightness is diminished by two tenths of a magnitude due to interstellar dust and Eggen (1993) lists it as a member of the old disk population. It has an absolute magnitude of +0.83.

Gamma³ Octantis has a stellar classification of K1/2 III, indicating that it is an evolved K-type star with the characteristics of a K1 and K2 giant star. It is a red clump star that is currently on the horizontal branch, fusing helium at its core. At present it has 2.23 times the mass of the Sun but has expanded to almost 10 times its girth. It radiates 50.5 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,879 K, which gives it a yellowish-orange glow. Gamma³ Octantis is metal enriched with an iron abundance 1.55 times that of the Sun and common for giant stars, spins slowly with a projected rotational velocity less than Шаблон:Val.

Gap between stars sharing Gamma designation

The very similar brightness and potentially close stars of Gamma^{2, 3} have been examined by the Gaia space telescope/observatory. Gamma² is much more distant than the other two whose margins of error overlap when parallaxes are considered — they may thus be close enough to be in loose mutual orbital. These distances from our star system per Gaia's second Data Release (DR2) are, respectively, around 319 ± 5 ly and 259 ± 3 ly. The observation refines Gamma¹ as being 262 ± 4 ly away.