Atria

Designated Alpha Trianguli Australis, Atria carries the leading Bayer letter of the small southern constellation Triangulum Australe. It is an orange K-type star, a classification that places it among the cooler, evolved stars whose light peaks toward the red end of the visible spectrum — a character borne out by its measured colour index of 1.45. Atria shines at apparent visual magnitude 1.91, keeping it comfortably within naked-eye range, yet its absolute magnitude of −3.48 reveals a far greater intrinsic output than that modest apparent brightness suggests. The difference is a matter of distance: the star lies roughly 391 light-years from the Solar System, so its considerable luminosity is diminished by the long path its light must travel.