Saio et al. created a model that simulated Betelgeuse’s pulsations and say it provides unique insight into the star’s internal status. The only way for Betelgeuse to pulsate in this way is if it is at the very end of its carbon burning period. That means the collapse of this star’s core and the accompanying supernova is imminent. “After carbon is exhausted in the core, a core-collapse leading to a supernova explosion is expected in a few tens of years,” they conclude.
It’s so wild to think that a star so close to us is dying just moments after we understood how stars die.