Vol. 24 No. 1 (2025): Mapana Journal of Sciences
Review Articles

Luminous Blue Variables: A Step Towards Exploring a Critical Phase in Massive Star Evolution

  • Prasoon Ashok Singh,
  • Gourav Banerjee,
  • Arun Roy,
  • Blessen Matthew,
  • Maheswar Gopinathan
Prasoon Ashok Singh
Indian Institute of Astrophysics

Published 2025-04-12

Keywords

  • Luminous Blue Variables,
  • Massive stars,
  • Stellar evolution

Copyright (c) 2025

Creative Commons License

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

Abstract

Luminous Blue Variables (LBVs) are a rare class of early type, bright variable stars of late O to A spectral types that
represent one of the most enigmatic phases in the evolution of massive stars. Optical spectra of LBVs display prominent
emission lines of HI, HeI, FeII, and [FeII], often showing P Cygni-type profiles indicating mass loss. Traditionally, LBVs
have been viewed as a transitional phase between massive O-type and Wolf-Rayet stars, marked by significant mass
loss, 10 to 100 times compared to normal supergiant stars having similar luminosity, through episodes of eruptions and strong winds. However, these enigmatic objects still remain mysterious but important to better understand the
life cycle of massive stars, motivating further investigations to unravel their true nature. In this article, we provide an introduction to the various observable properties of LBVs and explore both traditional and alternate models of their
origin. The article is written to motivate both young readers and scholars of the astronomy community by highlighting the importance of exploring these rare but exotic stars, the LBVs

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