Betelgeuse’s strangeness explained by stellar cannibalism incident

Betelgeuse is one of the brightest stars in the sky, and we are amazed not only by the power of its brilliance, but also by its mysterious behavior. For this reason, scientists must carefully observe it and try to deduce its future fate and evolutionary features. In particular, new research suggests that the star may engage in cannibalism, thereby welcoming smaller companions into the system.

Betelgeuse differs from other red giant stars observed in the universe (giants in the final stage of their life cycle before going supernova) in two observable parameters. First, it spins faster than any of its siblings. Second, its atmosphere contains an excessive number of heavy atoms, especially nitrogen (for astrophysicists, anything heavier than helium is considered heavy). The high rotation rate and very high heavy element concentrations suggest that Betelgeuse’s evolution was extraordinary. The most likely situation is that the star has swallowed a smaller partner in the system. Fortunately, there are not only a lot of binary star systems in the universe, but a lot of them. With the help of computer models, this question can be answered more or less clearly. The computer actually calculated the conditions under which her two stars in the system could produce Betelgeuse with the properties we currently observe.

Calculations show that the red giant star, which has a mass 16 times the mass of the Sun and whose core has burned out into helium, gradually shed its atmosphere and spread into the orbit of a smaller companion star. It is a still active star with a mass about four times the mass of the Sun. The small companion star gained mass, slowed down, and eventually merged with the larger star. Although this merger occurred “quietly” without significant mass loss, it resulted in the destruction of the helium core, the mixing of the star’s mass, the ejection of large amounts of heavy elements into the atmosphere, and the acceleration of its rotation due to additional momentum. I did. . This scenario can only be confirmed by observing a supernova that turns Betelgeuse into a supernova. Information on this is obtained from the composition and proportions of heavy elements in the explosion products. But that will take 50,000 to 100,000 years. However, some astronomers believe that Betelgeuse could become a supernova within 30 years.