The half-century history of studies of Romano's star

TL;DR

This paper reviews fifty years of research on Romano's star, an LBV/post-LBV object, highlighting its significance for understanding massive star evolution and the challenges in studying such rare stars both in our galaxy and nearby galaxies.

Contribution

It provides a comprehensive historical overview of studies on Romano's star, emphasizing its importance in the context of LBV research and stellar evolution.

Findings

Romano's star exhibits characteristics of LBV/post-LBV stars.

Studying extragalactic LBVs like Romano's star helps overcome observational challenges.

Romano's star offers insights into the evolution of massive stars.

Abstract

Luminous blue variables (LBVs) are rare objects of very high luminosity and mass loss rates, low wind velocities, exhibiting strong irregular photometric and spectral variability. They are generally believed to be a relatively short evolutionary stage in the life of a massive star, marking the transition from the Main Sequence toward Wolf-Rayet (WR) stars. However, recent studies indicate that progenitors of several supernovae underwent LBV-like eruptions. These studies support the view that at least some LBV stars are the end point of the evolution but not a transition phase. LBVs are rare objects, observations of whose in the Galaxy are inevitably connected with difficulties in determination of the distance and interstellar extinction. Hence, studying these rare objects in nearby galaxies is potentially more prospective. Therefore, investigation of the extragalactic star Romano's star (V532 or GR290) which is now classified as LBV/post-LBV star and shows late-WN spectrum, is very important for our understanding of evolution of massive stars in general.