Phi-2

Its story

Phi-2 Orionis forms with Meissa and Phi-1 a small triangle at the hunter's head, just above the three stars of the belt. She is a yellow subgiant older than the Sun by some seven billion years and already starting to swell: with barely more mass, she has grown to eight solar radii and burns thirty times brighter. At 117 light-years she shows in miniature what the Sun will do in five billion years.