@AkomoCombine Luminous blue variables (LBVs) are rare, unstable stars that undergo extreme changes in brightness. They are the hottest and most luminous stars known to exist and, because of their extreme brightness, they are also very bright in the ultraviolet range of the spectrum. LBVs represent a short-lived evolutionary stage in the life cycles of some massive stars, prior to entering a supernova or Wolf-Rayet phase.