The evolutionary relationships and mechanisms governing the behavior of the wide variety of luminous stars populating the upper H-R diagram are not well established. Luminous blue variables (LBVs) are particularly rare, with only a few dozen identified in the Milky Way and nearby galaxies. Since 2012, the Barber Observatory Luminous Stars Survey has monitored more than 100 luminous targets in M33, including M33C-4119 which has recently undergone photometric and spectroscopic changes consistent with an S Doradus eruption of an LBV.
@article{arxiv.2305.11687,
title = {A New LBV Candidate in M33},
author = {John C. Martin and Roberta M. Humphreys and Kerstin Weis and Dominik J. Bohmans},
journal= {arXiv preprint arXiv:2305.11687},
year = {2023}
}