Shedding of large mass had caused the dimming of Betelgeuse

Around the end of 2019, one of the stars in Orion Nebula, the Betelgeuse had excited scientists and people around the world because of its unusual dimming in brightness. People were speculating that it could go supernova at any time and we would be the lucky ones who would witness such a spectacular event in space relatively close to our solar system. However, after some time the star regained it's brightness and at least I was a bit disappointed. It turns out that Betelgeuse had shed a large mass from its outer layers in the direction of our view. The mass also contained a lot of dust which blocked a portion of light coming towards us, thus dimming its brightness.

 

 

 Image source: https://science.nasa.gov/wp-content/uploads/2023/04/stsci-h-p2044a-f-3930x1748-1-jpg.webp?w=2048&format=webp 

Stars of masses between 8 to 35 times that of the Sun undergo a stage of red super-giant during the last phases of their life. This phase lasts for about one lakh years (100 thousand years). During this time, the star shed a lot of mass. Stars like Betelgeuse, in this stage are not even spherical anymore but have globules protruding out of them trying to explode but held by the stars gravity. The actual mechanism of how exactly the mass shedding happens is still being explored. 

The observation of the star in high-angular resolution revealed that a dust cloud had formed in the southern region of Betelgeuse. The dust cloud was emitted towards the direction of Earth thus coming between our view of the star. These kind of events of mass shedding would happen in future with Betelgeuse thus changing its apparent brightness. Betelgeuse will eventually go supernova but it doesn't seem to happening within our lifetimes. 

Original article: https://www.nature.com/articles/s41586-021-03546-8