Original article: "The dramatic transition of the extreme red supergiant WOH G64 to a yellow hypergiant" - https://www.nature.com/articles/s41550-026-02789-7

Abstract: "Red supergiants (RSGs) are cool, evolved massive stars in their final evolutionary stage before exploding as a supernova. However, the evolution and fate of the most luminous RSGs remain uncertain. Observational evidence for luminous warm, post-RSG objects and the apparent lack of luminous RSGs as supernova progenitors suggest a bluewards evolution. Since the 1980s, WOH G64 has been considered the most extreme RSG in the Large Magellanic Cloud, given its large obscuration, outstanding size, luminosity and mass-loss rate. Here we report a sudden, yet smooth change in its apparent nature. Time-series photometry and subsequent spectroscopy reveal an extreme transition in the optical spectral features. We conclude that WOH G64 is a rare, massive symbiotic binary system where the RSG component has transitioned to a yellow hypergiant. This drastic transformation can be explained either by the partial ejection of the pseudo-atmosphere during a common-envelope phase or the return to a quiescent state after an outstanding eruption exceeding 30 years in duration. WOH G64 offers an opportunity to witness stellar evolution in real time and assess the role of binarity on the final phases of massive stars and their resulting supernovae."

Save yourself $40. It's free at arxiv.

Damn highwaymen, MITM's.

The dramatic transition of the extreme Red Supergiant WOH G64 to a Yellow Hypergiant

G. Munoz-Sanchez, M. Kalitsounaki, S. de Wit, K. Antoniadis, A.Z. Bonanos, E. Zapartas, K. Boutsia, E. Christodoulou, G. Maravelias, I. Soszynski, A. Udalski

    Red Supergiants (RSGs) are cool, evolved massive stars in their final evolutionary stage before exploding as a supernova.  ...

https://arxiv.org/abs/2411.19329