Arcus

Arcus, also known as CelWP G17, is a Red giant star and a Mira blue variable in Triangulum's spiral arms. Its notable as being the origin and source of the extremely well-known Arcus Nebula, hence the star's name. Over a pulsation period of 113.6 days, its radius varies between 869.4 RSun and 1062.6 RSun. Its initial mass is not well-known, but its estimated to be somewhere between 17 MSun and 26 MSun. In real life, its named M33SSS J013300.38+303416.8.

Notoriety and its status as a Thorne-Zytkow Object
Arcus has been heaviily studied due to its relatively recent confirmation of its nature as a Thorne-Zytkow object, having a neutron star in its core. This inspired scientists all over the galaxy to observe it, and several missions were designed for Arcusan exploration. Today, Arcus is an extremely popular tourist destination for the entire population of Triangulum.